Merge pull request #2069 from Trial97/feature/java-downloader

Feature/java downloader

.github/workflows/build.yml

@@ -266,23 +266,23 @@ jobs:
       - name: Configure CMake (macOS)
         if: runner.os == 'macOS' && matrix.qt_ver == 6
         run: |
-          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DCMAKE_OSX_ARCHITECTURES="x86_64;arm64" -G Ninja
+          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DENABLE_JAVA_DOWNLOADER=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DCMAKE_OSX_ARCHITECTURES="x86_64;arm64" -G Ninja
 
       - name: Configure CMake (macOS-Legacy)
         if: runner.os == 'macOS' && matrix.qt_ver == 5
         run: |
-          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DMACOSX_SPARKLE_UPDATE_PUBLIC_KEY="" -DMACOSX_SPARKLE_UPDATE_FEED_URL="" -G Ninja
+          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DENABLE_JAVA_DOWNLOADER=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DMACOSX_SPARKLE_UPDATE_PUBLIC_KEY="" -DMACOSX_SPARKLE_UPDATE_FEED_URL="" -G Ninja
 
       - name: Configure CMake (Windows MinGW-w64)
         if: runner.os == 'Windows' && matrix.msystem != ''
         shell: msys2 {0}
         run: |
-          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=6 -DCMAKE_OBJDUMP=/mingw64/bin/objdump.exe -DLauncher_BUILD_ARTIFACT=${{ matrix.name }}-Qt${{ matrix.qt_ver }} -G Ninja
+          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DENABLE_JAVA_DOWNLOADER=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=6 -DCMAKE_OBJDUMP=/mingw64/bin/objdump.exe -DLauncher_BUILD_ARTIFACT=${{ matrix.name }}-Qt${{ matrix.qt_ver }} -G Ninja
 
       - name: Configure CMake (Windows MSVC)
         if: runner.os == 'Windows' && matrix.msystem == ''
         run: |
-          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DLauncher_BUILD_PLATFORM=official -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DCMAKE_MSVC_RUNTIME_LIBRARY="MultiThreadedDLL" -A${{ matrix.architecture}} -DLauncher_FORCE_BUNDLED_LIBS=ON  -DLauncher_BUILD_ARTIFACT=${{ matrix.name }}-Qt${{ matrix.qt_ver }}
+          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=${{ env.INSTALL_DIR }} -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DENABLE_JAVA_DOWNLOADER=ON -DLauncher_BUILD_PLATFORM=official -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DCMAKE_MSVC_RUNTIME_LIBRARY="MultiThreadedDLL" -A${{ matrix.architecture}} -DLauncher_FORCE_BUNDLED_LIBS=ON  -DLauncher_BUILD_ARTIFACT=${{ matrix.name }}-Qt${{ matrix.qt_ver }}
           # https://github.com/ccache/ccache/wiki/MS-Visual-Studio (I coudn't figure out the compiler prefix)
           if ("${{ env.CCACHE_VAR }}")
           {
@@ -297,7 +297,7 @@ jobs:
       - name: Configure CMake (Linux)
         if: runner.os == 'Linux'
         run: |
-          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DLauncher_BUILD_ARTIFACT=Linux-Qt${{ matrix.qt_ver }} -G Ninja
+          cmake -S . -B ${{ env.BUILD_DIR }} -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} -DENABLE_LTO=ON -DENABLE_JAVA_DOWNLOADER=ON -DLauncher_BUILD_PLATFORM=official -DCMAKE_C_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DCMAKE_CXX_COMPILER_LAUNCHER=${{ env.CCACHE_VAR }} -DLauncher_QT_VERSION_MAJOR=${{ matrix.qt_ver }} -DLauncher_BUILD_ARTIFACT=Linux-Qt${{ matrix.qt_ver }} -G Ninja
 
       ##
       # BUILD

CMakeLists.txt

@@ -219,6 +219,19 @@ set(Launcher_SUBREDDIT_URL "https://prismlauncher.org/reddit" CACHE STRING "URL
 set(Launcher_FORCE_BUNDLED_LIBS OFF CACHE BOOL "Prevent using system libraries, if they are available as submodules")
 set(Launcher_QT_VERSION_MAJOR "6" CACHE STRING "Major Qt version to build against")
 
+# Java downloader
+set(ENABLE_JAVA_DOWNLOADER_DEFAULT ON)
+
+# Although we recommend enabling this, we cannot guarantee binary compatibility on 
+# differing Linux/BSD/etc distributions. Downstream packagers should be explicitly opt-ing into this
+# feature if they know it will work with their distribution.
+if(UNIX AND NOT APPLE)
+  set(ENABLE_JAVA_DOWNLOADER_DEFAULT OFF)
+endif()
+
+# Java downloader
+option(ENABLE_JAVA_DOWNLOADER "Build the java downloader feature" ${ENABLE_JAVA_DOWNLOADER_DEFAULT})
+
 # Native libraries
 if(UNIX AND APPLE)
     set(Launcher_GLFW_LIBRARY_NAME "libglfw.dylib" CACHE STRING "Name of native glfw library")

buildconfig/BuildConfig.cpp.in

@@ -81,6 +81,9 @@ Config::Config()
         UPDATER_ENABLED = true;
     }
 
+    #cmakedefine01 ENABLE_JAVA_DOWNLOADER
+    JAVA_DOWNLOADER_ENABLED = ENABLE_JAVA_DOWNLOADER;
+
     GIT_COMMIT = "@Launcher_GIT_COMMIT@";
     GIT_TAG = "@Launcher_GIT_TAG@";
     GIT_REFSPEC = "@Launcher_GIT_REFSPEC@";

buildconfig/BuildConfig.h

@@ -67,6 +67,7 @@ class Config {
     QString VERSION_CHANNEL;
 
     bool UPDATER_ENABLED = false;
+    bool JAVA_DOWNLOADER_ENABLED = false;
 
     /// A short string identifying this build's platform or distribution.
     QString BUILD_PLATFORM;

launcher/Application.cpp

@@ -44,6 +44,7 @@
 #include "BuildConfig.h"
 
 #include "DataMigrationTask.h"
+#include "java/JavaInstallList.h"
 #include "net/PasteUpload.h"
 #include "pathmatcher/MultiMatcher.h"
 #include "pathmatcher/SimplePrefixMatcher.h"
@@ -125,6 +126,7 @@
 
 #include <stdlib.h>
 #include <sys.h>
+#include "SysInfo.h"
 
 #ifdef Q_OS_LINUX
 #include <dlfcn.h>
@@ -602,6 +604,7 @@ Application::Application(int& argc, char** argv) : QApplication(argc, argv)
         m_settings->registerSetting("DownloadsDir", QStandardPaths::writableLocation(QStandardPaths::DownloadLocation));
         m_settings->registerSetting("DownloadsDirWatchRecursive", false);
         m_settings->registerSetting("SkinsDir", "skins");
+        m_settings->registerSetting("JavaDir", "java");
 
         // Editors
         m_settings->registerSetting("JsonEditor", QString());
@@ -630,7 +633,7 @@ Application::Application(int& argc, char** argv) : QApplication(argc, argv)
 
         // Memory
         m_settings->registerSetting({ "MinMemAlloc", "MinMemoryAlloc" }, 512);
-        m_settings->registerSetting({ "MaxMemAlloc", "MaxMemoryAlloc" }, suitableMaxMem());
+        m_settings->registerSetting({ "MaxMemAlloc", "MaxMemoryAlloc" }, SysInfo::suitableMaxMem());
         m_settings->registerSetting("PermGen", 128);
 
         // Java Settings
@@ -644,6 +647,9 @@ Application::Application(int& argc, char** argv) : QApplication(argc, argv)
         m_settings->registerSetting("JvmArgs", "");
         m_settings->registerSetting("IgnoreJavaCompatibility", false);
         m_settings->registerSetting("IgnoreJavaWizard", false);
+        auto defaultEnableAutoJava = m_settings->get("JavaPath").toString().isEmpty();
+        m_settings->registerSetting("AutomaticJavaSwitch", defaultEnableAutoJava);
+        m_settings->registerSetting("AutomaticJavaDownload", defaultEnableAutoJava);
 
         // Legacy settings
         m_settings->registerSetting("OnlineFixes", false);
@@ -873,6 +879,7 @@ Application::Application(int& argc, char** argv) : QApplication(argc, argv)
         m_metacache->addBase("ModrinthModpacks", QDir("cache/ModrinthModpacks").absolutePath());
         m_metacache->addBase("translations", QDir("translations").absolutePath());
         m_metacache->addBase("meta", QDir("meta").absolutePath());
+        m_metacache->addBase("java", QDir("cache/java").absolutePath());
         m_metacache->Load();
         qDebug() << "<> Cache initialized.";
     }
@@ -1740,20 +1747,6 @@ QString Application::getUserAgentUncached()
     return BuildConfig.USER_AGENT_UNCACHED;
 }
 
-int Application::suitableMaxMem()
-{
-    float totalRAM = (float)Sys::getSystemRam() / (float)Sys::mebibyte;
-    int maxMemoryAlloc;
-
-    // If totalRAM < 6GB, use (totalRAM / 1.5), else 4GB
-    if (totalRAM < (4096 * 1.5))
-        maxMemoryAlloc = (int)(totalRAM / 1.5);
-    else
-        maxMemoryAlloc = 4096;
-
-    return maxMemoryAlloc;
-}
-
 bool Application::handleDataMigration(const QString& currentData,
                                       const QString& oldData,
                                       const QString& name,
@@ -1860,3 +1853,7 @@ QUrl Application::normalizeImportUrl(QString const& url)
         return QUrl::fromUserInput(url);
     }
 }
+const QString Application::javaPath()
+{
+    return m_settings->get("JavaDir").toString();
+}

launcher/Application.h

@@ -161,6 +161,9 @@ class Application : public QApplication {
     /// the data path the application is using
     const QString& dataRoot() { return m_dataPath; }
 
+    /// the java installed path the application is using
+    const QString javaPath();
+
     bool isPortable() { return m_portable; }
 
     const Capabilities capabilities() { return m_capabilities; }
@@ -179,8 +182,6 @@ class Application : public QApplication {
 
     void ShowGlobalSettings(class QWidget* parent, QString open_page = QString());
 
-    int suitableMaxMem();
-
     bool updaterEnabled();
     QString updaterBinaryName();
 

launcher/BaseVersionList.cpp

@@ -78,6 +78,14 @@ QVariant BaseVersionList::data(const QModelIndex& index, int role) const
         case TypeRole:
             return version->typeString();
 
+        case JavaMajorRole: {
+            auto major = version->name();
+            if (major.startsWith("java")) {
+                major = "Java " + major.mid(4);
+            }
+            return major;
+        }
+
         default:
             return QVariant();
     }
@@ -110,6 +118,8 @@ QHash<int, QByteArray> BaseVersionList::roleNames() const
     roles.insert(TypeRole, "type");
     roles.insert(BranchRole, "branch");
     roles.insert(PathRole, "path");
-    roles.insert(ArchitectureRole, "architecture");
+    roles.insert(JavaNameRole, "javaName");
+    roles.insert(CPUArchitectureRole, "architecture");
+    roles.insert(JavaMajorRole, "javaMajor");
     return roles;
 }

launcher/BaseVersionList.h

@@ -48,7 +48,9 @@ class BaseVersionList : public QAbstractListModel {
         TypeRole,
         BranchRole,
         PathRole,
-        ArchitectureRole,
+        JavaNameRole,
+        JavaMajorRole,
+        CPUArchitectureRole,
         SortRole
     };
     using RoleList = QList<int>;

launcher/CMakeLists.txt

@@ -24,6 +24,8 @@ set(CORE_SOURCES
     NullInstance.h
     MMCZip.h
     MMCZip.cpp
+    Untar.h
+    Untar.cpp
     StringUtils.h
     StringUtils.cpp
     QVariantUtils.h
@@ -272,6 +274,8 @@ set(MINECRAFT_SOURCES
     minecraft/launch/ScanModFolders.h
     minecraft/launch/VerifyJavaInstall.cpp
     minecraft/launch/VerifyJavaInstall.h
+    minecraft/launch/AutoInstallJava.cpp
+    minecraft/launch/AutoInstallJava.h
 
     minecraft/GradleSpecifier.h
     minecraft/MinecraftInstance.cpp
@@ -417,8 +421,6 @@ set(SETTINGS_SOURCES
 set(JAVA_SOURCES
     java/JavaChecker.h
     java/JavaChecker.cpp
-    java/JavaCheckerJob.h
-    java/JavaCheckerJob.cpp
     java/JavaInstall.h
     java/JavaInstall.cpp
     java/JavaInstallList.h
@@ -427,6 +429,18 @@ set(JAVA_SOURCES
     java/JavaUtils.cpp
     java/JavaVersion.h
     java/JavaVersion.cpp
+
+    java/JavaMetadata.h
+    java/JavaMetadata.cpp
+    java/download/ArchiveDownloadTask.cpp
+    java/download/ArchiveDownloadTask.h
+    java/download/ManifestDownloadTask.cpp
+    java/download/ManifestDownloadTask.h
+
+    ui/java/InstallJavaDialog.h
+    ui/java/InstallJavaDialog.cpp
+    ui/java/VersionList.h
+    ui/java/VersionList.cpp
 )
 
 set(TRANSLATIONS_SOURCES
@@ -746,6 +760,8 @@ SET(LAUNCHER_SOURCES
     DataMigrationTask.cpp
     ApplicationMessage.h
     ApplicationMessage.cpp
+    SysInfo.h
+    SysInfo.cpp
 
     # GUI - general utilities
     DesktopServices.h

launcher/FileSystem.cpp

@@ -276,6 +276,9 @@ bool ensureFolderPathExists(const QFileInfo folderPath)
 {
     QDir dir;
     QString ensuredPath = folderPath.filePath();
+    if (folderPath.exists())
+        return true;
+
     bool success = dir.mkpath(ensuredPath);
     return success;
 }

launcher/Filter.cpp

@@ -1,16 +1,12 @@
 #include "Filter.h"
 
-Filter::~Filter() {}
-
 ContainsFilter::ContainsFilter(const QString& pattern) : pattern(pattern) {}
-ContainsFilter::~ContainsFilter() {}
 bool ContainsFilter::accepts(const QString& value)
 {
     return value.contains(pattern);
 }
 
 ExactFilter::ExactFilter(const QString& pattern) : pattern(pattern) {}
-ExactFilter::~ExactFilter() {}
 bool ExactFilter::accepts(const QString& value)
 {
     return value == pattern;
@@ -27,10 +23,15 @@ RegexpFilter::RegexpFilter(const QString& regexp, bool invert) : invert(invert)
     pattern.setPattern(regexp);
     pattern.optimize();
 }
-RegexpFilter::~RegexpFilter() {}
 bool RegexpFilter::accepts(const QString& value)
 {
     auto match = pattern.match(value);
     bool matched = match.hasMatch();
     return invert ? (!matched) : (matched);
 }
+
+ExactListFilter::ExactListFilter(const QStringList& pattern) : m_pattern(pattern) {}
+bool ExactListFilter::accepts(const QString& value)
+{
+    return m_pattern.isEmpty() || m_pattern.contains(value);
+}

launcher/Filter.h

@@ -5,14 +5,14 @@
 
 class Filter {
    public:
-    virtual ~Filter();
+    virtual ~Filter() = default;
     virtual bool accepts(const QString& value) = 0;
 };
 
 class ContainsFilter : public Filter {
    public:
     ContainsFilter(const QString& pattern);
-    virtual ~ContainsFilter();
+    virtual ~ContainsFilter() = default;
     bool accepts(const QString& value) override;
 
    private:
@@ -22,7 +22,7 @@ class ContainsFilter : public Filter {
 class ExactFilter : public Filter {
    public:
     ExactFilter(const QString& pattern);
-    virtual ~ExactFilter();
+    virtual ~ExactFilter() = default;
     bool accepts(const QString& value) override;
 
    private:
@@ -32,7 +32,7 @@ class ExactFilter : public Filter {
 class ExactIfPresentFilter : public Filter {
    public:
     ExactIfPresentFilter(const QString& pattern);
-    ~ExactIfPresentFilter() override = default;
+    virtual ~ExactIfPresentFilter() override = default;
     bool accepts(const QString& value) override;
 
    private:
@@ -42,10 +42,20 @@ class ExactIfPresentFilter : public Filter {
 class RegexpFilter : public Filter {
    public:
     RegexpFilter(const QString& regexp, bool invert);
-    virtual ~RegexpFilter();
+    virtual ~RegexpFilter() = default;
     bool accepts(const QString& value) override;
 
    private:
     QRegularExpression pattern;
     bool invert = false;
 };
+
+class ExactListFilter : public Filter {
+   public:
+    ExactListFilter(const QStringList& pattern = {});
+    virtual ~ExactListFilter() = default;
+    bool accepts(const QString& value) override;
+
+   private:
+    const QStringList& m_pattern;
+};

launcher/JavaCommon.cpp

@@ -63,7 +63,7 @@ bool JavaCommon::checkJVMArgs(QString jvmargs, QWidget* parent)
     return true;
 }
 
-void JavaCommon::javaWasOk(QWidget* parent, const JavaCheckResult& result)
+void JavaCommon::javaWasOk(QWidget* parent, const JavaChecker::Result& result)
 {
     QString text;
     text += QObject::tr(
@@ -79,7 +79,7 @@ void JavaCommon::javaWasOk(QWidget* parent, const JavaCheckResult& result)
     CustomMessageBox::selectable(parent, QObject::tr("Java test success"), text, QMessageBox::Information)->show();
 }
 
-void JavaCommon::javaArgsWereBad(QWidget* parent, const JavaCheckResult& result)
+void JavaCommon::javaArgsWereBad(QWidget* parent, const JavaChecker::Result& result)
 {
     auto htmlError = result.errorLog;
     QString text;
@@ -89,7 +89,7 @@ void JavaCommon::javaArgsWereBad(QWidget* parent, const JavaCheckResult& result)
     CustomMessageBox::selectable(parent, QObject::tr("Java test failure"), text, QMessageBox::Warning)->show();
 }
 
-void JavaCommon::javaBinaryWasBad(QWidget* parent, const JavaCheckResult& result)
+void JavaCommon::javaBinaryWasBad(QWidget* parent, const JavaChecker::Result& result)
 {
     QString text;
     text += QObject::tr(
@@ -116,34 +116,26 @@ void JavaCommon::TestCheck::run()
         emit finished();
         return;
     }
-    checker.reset(new JavaChecker());
+    checker.reset(new JavaChecker(m_path, "", 0, 0, 0, 0, this));
     connect(checker.get(), &JavaChecker::checkFinished, this, &JavaCommon::TestCheck::checkFinished);
-    checker->m_path = m_path;
+    checker->start();
-    checker->performCheck();
 }
 
-void JavaCommon::TestCheck::checkFinished(JavaCheckResult result)
+void JavaCommon::TestCheck::checkFinished(const JavaChecker::Result& result)
 {
-    if (result.validity != JavaCheckResult::Validity::Valid) {
+    if (result.validity != JavaChecker::Result::Validity::Valid) {
         javaBinaryWasBad(m_parent, result);
         emit finished();
         return;
     }
-    checker.reset(new JavaChecker());
+    checker.reset(new JavaChecker(m_path, m_args, m_maxMem, m_maxMem, result.javaVersion.requiresPermGen() ? m_permGen : 0, 0, this));
     connect(checker.get(), &JavaChecker::checkFinished, this, &JavaCommon::TestCheck::checkFinishedWithArgs);
-    checker->m_path = m_path;
+    checker->start();
-    checker->m_args = m_args;
-    checker->m_minMem = m_minMem;
-    checker->m_maxMem = m_maxMem;
-    if (result.javaVersion.requiresPermGen()) {
-        checker->m_permGen = m_permGen;
-    }
-    checker->performCheck();
 }
 
-void JavaCommon::TestCheck::checkFinishedWithArgs(JavaCheckResult result)
+void JavaCommon::TestCheck::checkFinishedWithArgs(const JavaChecker::Result& result)
 {
-    if (result.validity == JavaCheckResult::Validity::Valid) {
+    if (result.validity == JavaChecker::Result::Validity::Valid) {
         javaWasOk(m_parent, result);
         emit finished();
         return;

launcher/JavaCommon.h

@@ -10,11 +10,11 @@ namespace JavaCommon {
 bool checkJVMArgs(QString args, QWidget* parent);
 
 // Show a dialog saying that the Java binary was usable
-void javaWasOk(QWidget* parent, const JavaCheckResult& result);
+void javaWasOk(QWidget* parent, const JavaChecker::Result& result);
 // Show a dialog saying that the Java binary was not usable because of bad options
-void javaArgsWereBad(QWidget* parent, const JavaCheckResult& result);
+void javaArgsWereBad(QWidget* parent, const JavaChecker::Result& result);
 // Show a dialog saying that the Java binary was not usable
-void javaBinaryWasBad(QWidget* parent, const JavaCheckResult& result);
+void javaBinaryWasBad(QWidget* parent, const JavaChecker::Result& result);
 // Show a dialog if we couldn't find Java Checker
 void javaCheckNotFound(QWidget* parent);
 
@@ -32,11 +32,11 @@ class TestCheck : public QObject {
     void finished();
 
    private slots:
-    void checkFinished(JavaCheckResult result);
+    void checkFinished(const JavaChecker::Result& result);
-    void checkFinishedWithArgs(JavaCheckResult result);
+    void checkFinishedWithArgs(const JavaChecker::Result& result);
 
    private:
-    std::shared_ptr<JavaChecker> checker;
+    JavaChecker::Ptr checker;
     QWidget* m_parent = nullptr;
     QString m_path;
     QString m_args;

launcher/MMCZip.cpp

@@ -2,7 +2,7 @@
 /*
  *  Prism Launcher - Minecraft Launcher
  *  Copyright (C) 2022 Sefa Eyeoglu <contact@scrumplex.net>
- *  Copyright (c) 2023 Trial97 <alexandru.tripon97@gmail.com>
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
  *
  *  This program is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -536,6 +536,10 @@ bool ExportToZipTask::abort()
 
 void ExtractZipTask::executeTask()
 {
+    if (!m_input->isOpen() && !m_input->open(QuaZip::mdUnzip)) {
+        emitFailed(tr("Unable to open supplied zip file."));
+        return;
+    }
     m_zip_future = QtConcurrent::run(QThreadPool::globalInstance(), [this]() { return extractZip(); });
     connect(&m_zip_watcher, &QFutureWatcher<ZipResult>::finished, this, &ExtractZipTask::finish);
     m_zip_watcher.setFuture(m_zip_future);

launcher/MMCZip.h

@@ -2,7 +2,7 @@
 /*
  *  Prism Launcher - Minecraft Launcher
  *  Copyright (C) 2022 Sefa Eyeoglu <contact@scrumplex.net>
- *  Copyright (c) 2023 Trial97 <alexandru.tripon97@gmail.com>
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
  *
  *  This program is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -208,6 +208,9 @@ class ExportToZipTask : public Task {
 
 class ExtractZipTask : public Task {
    public:
+    ExtractZipTask(QString input, QDir outputDir, QString subdirectory = "")
+        : ExtractZipTask(std::make_shared<QuaZip>(input), outputDir, subdirectory)
+    {}
     ExtractZipTask(std::shared_ptr<QuaZip> input, QDir outputDir, QString subdirectory = "")
         : m_input(input), m_output_dir(outputDir), m_subdirectory(subdirectory)
     {}

launcher/SysInfo.cpp

@@ -0,0 +1,99 @@
+#include <QDebug>
+#include <QString>
+#include "sys.h"
+#ifdef Q_OS_MACOS
+#include <sys/sysctl.h>
+#endif
+#include <QFile>
+#include <QMap>
+#include <QProcess>
+#include <QStandardPaths>
+
+#ifdef Q_OS_MACOS
+bool rosettaDetect()
+{
+    int ret = 0;
+    size_t size = sizeof(ret);
+    if (sysctlbyname("sysctl.proc_translated", &ret, &size, NULL, 0) == -1) {
+        return false;
+    }
+    return ret == 1;
+}
+#endif
+
+namespace SysInfo {
+QString currentSystem()
+{
+#if defined(Q_OS_LINUX)
+    return "linux";
+#elif defined(Q_OS_MACOS)
+    return "osx";
+#elif defined(Q_OS_WINDOWS)
+    return "windows";
+#elif defined(Q_OS_FREEBSD)
+    return "freebsd";
+#elif defined(Q_OS_OPENBSD)
+    return "openbsd";
+#else
+    return "unknown";
+#endif
+}
+
+QString useQTForArch()
+{
+#if defined(Q_OS_MACOS) && !defined(Q_PROCESSOR_ARM)
+    if (rosettaDetect()) {
+        return "arm64";
+    } else {
+        return "x86_64";
+    }
+#endif
+    return QSysInfo::currentCpuArchitecture();
+}
+
+int suitableMaxMem()
+{
+    float totalRAM = (float)Sys::getSystemRam() / (float)Sys::mebibyte;
+    int maxMemoryAlloc;
+
+    // If totalRAM < 6GB, use (totalRAM / 1.5), else 4GB
+    if (totalRAM < (4096 * 1.5))
+        maxMemoryAlloc = (int)(totalRAM / 1.5);
+    else
+        maxMemoryAlloc = 4096;
+
+    return maxMemoryAlloc;
+}
+
+QString getSupportedJavaArchitecture()
+{
+    auto sys = currentSystem();
+    auto arch = useQTForArch();
+    if (sys == "windows") {
+        if (arch == "x86_64")
+            return "windows-x64";
+        if (arch == "i386")
+            return "windows-x86";
+        // Unknown, maybe arm, appending arch
+        return "windows-" + arch;
+    }
+    if (sys == "osx") {
+        if (arch == "arm64")
+            return "mac-os-arm64";
+        if (arch.contains("64"))
+            return "mac-os-64";
+        if (arch.contains("86"))
+            return "mac-os-86";
+        // Unknown, maybe something new, appending arch
+        return "mac-os-" + arch;
+    } else if (sys == "linux") {
+        if (arch == "x86_64")
+            return "linux-x64";
+        if (arch == "i386")
+            return "linux-x86";
+        // will work for arm32 arm(64)
+        return "linux-" + arch;
+    }
+    return {};
+}
+}  // namespace SysInfo

launcher/SysInfo.h

@@ -0,0 +1,8 @@
+#include <QString>
+
+namespace SysInfo {
+QString currentSystem();
+QString useQTForArch();
+QString getSupportedJavaArchitecture();
+int suitableMaxMem();
+}  // namespace SysInfo

launcher/Untar.cpp

@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ *      Copyright 2013-2021 MultiMC Contributors
+ *
+ *      Licensed under the Apache License, Version 2.0 (the "License");
+ *      you may not use this file except in compliance with the License.
+ *      You may obtain a copy of the License at
+ *
+ *          http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *      Unless required by applicable law or agreed to in writing, software
+ *      distributed under the License is distributed on an "AS IS" BASIS,
+ *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *      See the License for the specific language governing permissions and
+ *      limitations under the License.
+ */
+#include "Untar.h"
+#include <quagzipfile.h>
+#include <QByteArray>
+#include <QFileInfo>
+#include <QIODevice>
+#include <QString>
+#include "FileSystem.h"
+
+// adaptation of the:
+// - https://github.com/madler/zlib/blob/develop/contrib/untgz/untgz.c
+// - https://en.wikipedia.org/wiki/Tar_(computing)
+// - https://github.com/euroelessar/cutereader/blob/master/karchive/src/ktar.cpp
+
+#define BLOCKSIZE 512
+#define SHORTNAMESIZE 100
+
+enum class TypeFlag : char {
+    Regular = '0',     // regular file
+    ARegular = 0,      // regular file
+    Link = '1',        // link
+    Symlink = '2',     // reserved
+    Character = '3',   // character special
+    Block = '4',       // block special
+    Directory = '5',   // directory
+    FIFO = '6',        // FIFO special
+    Contiguous = '7',  // reserved
+    // Posix stuff
+    GlobalPosixHeader = 'g',
+    ExtendedPosixHeader = 'x',
+    // 'A'– 'Z' Vendor specific extensions(POSIX .1 - 1988)
+    // GNU
+    GNULongLink = 'K', /* long link name */
+    GNULongName = 'L', /* long file name */
+};
+
+// struct Header {         /* byte offset */
+//     char name[100];     /*   0 */
+//     char mode[8];       /* 100 */
+//     char uid[8];        /* 108 */
+//     char gid[8];        /* 116 */
+//     char size[12];      /* 124 */
+//     char mtime[12];     /* 136 */
+//     char chksum[8];     /* 148 */
+//     TypeFlag typeflag;  /* 156 */
+//     char linkname[100]; /* 157 */
+//     char magic[6];      /* 257 */
+//     char version[2];    /* 263 */
+//     char uname[32];     /* 265 */
+//     char gname[32];     /* 297 */
+//     char devmajor[8];   /* 329 */
+//     char devminor[8];   /* 337 */
+//     char prefix[155];   /* 345 */
+//                         /* 500 */
+// };
+
+bool readLonglink(QIODevice* in, qint64 size, QByteArray& longlink)
+{
+    qint64 n = 0;
+    size--;  // ignore trailing null
+    if (size < 0) {
+        qCritical() << "The filename size is negative";
+        return false;
+    }
+    longlink.resize(size + (BLOCKSIZE - size % BLOCKSIZE));  // make the size divisible by BLOCKSIZE
+    for (qint64 offset = 0; offset < longlink.size(); offset += BLOCKSIZE) {
+        n = in->read(longlink.data() + offset, BLOCKSIZE);
+        if (n != BLOCKSIZE) {
+            qCritical() << "The expected blocksize was not respected for the name";
+            return false;
+        }
+    }
+    longlink.truncate(qstrlen(longlink.constData()));
+    return true;
+}
+
+int getOctal(char* buffer, int maxlenght, bool* ok)
+{
+    return QByteArray(buffer, qstrnlen(buffer, maxlenght)).toInt(ok, 8);
+}
+
+QString decodeName(char* name)
+{
+    return QFile::decodeName(QByteArray(name, qstrnlen(name, 100)));
+}
+bool Tar::extract(QIODevice* in, QString dst)
+{
+    char buffer[BLOCKSIZE];
+    QString name, symlink, firstFolderName;
+    bool doNotReset = false, ok;
+    while (true) {
+        auto n = in->read(buffer, BLOCKSIZE);
+        if (n != BLOCKSIZE) {  // allways expect complete blocks
+            qCritical() << "The expected blocksize was not respected";
+            return false;
+        }
+        if (buffer[0] == 0) {  // end of archive
+            return true;
+        }
+        int mode = getOctal(buffer + 100, 8, &ok) | QFile::ReadUser | QFile::WriteUser;  // hack to ensure write and read permisions
+        if (!ok) {
+            qCritical() << "The file mode can't be read";
+            return false;
+        }
+        // there are names that are exactly 100 bytes long
+        // and neither longlink nor \0 terminated (bug:101472)
+
+        if (name.isEmpty()) {
+            name = decodeName(buffer);
+            if (!firstFolderName.isEmpty() && name.startsWith(firstFolderName)) {
+                name = name.mid(firstFolderName.size());
+            }
+        }
+        if (symlink.isEmpty())
+            symlink = decodeName(buffer);
+        qint64 size = getOctal(buffer + 124, 12, &ok);
+        if (!ok) {
+            qCritical() << "The file size can't be read";
+            return false;
+        }
+        switch (TypeFlag(buffer[156])) {
+            case TypeFlag::Regular:
+                /* fallthrough */
+            case TypeFlag::ARegular: {
+                auto fileName = FS::PathCombine(dst, name);
+                if (!FS::ensureFilePathExists(fileName)) {
+                    qCritical() << "Can't ensure the file path to exist: " << fileName;
+                    return false;
+                }
+                QFile out(fileName);
+                if (!out.open(QFile::WriteOnly)) {
+                    qCritical() << "Can't open file:" << fileName;
+                    return false;
+                }
+                out.setPermissions(QFile::Permissions(mode));
+                while (size > 0) {
+                    QByteArray tmp(BLOCKSIZE, 0);
+                    n = in->read(tmp.data(), BLOCKSIZE);
+                    if (n != BLOCKSIZE) {
+                        qCritical() << "The expected blocksize was not respected when reading file";
+                        return false;
+                    }
+                    tmp.truncate(qMin(qint64(BLOCKSIZE), size));
+                    out.write(tmp);
+                    size -= BLOCKSIZE;
+                }
+                break;
+            }
+            case TypeFlag::Directory: {
+                if (firstFolderName.isEmpty()) {
+                    firstFolderName = name;
+                    break;
+                }
+                auto folderPath = FS::PathCombine(dst, name);
+                if (!FS::ensureFolderPathExists(folderPath)) {
+                    qCritical() << "Can't ensure that folder exists: " << folderPath;
+                    return false;
+                }
+                break;
+            }
+            case TypeFlag::GNULongLink: {
+                doNotReset = true;
+                QByteArray longlink;
+                if (readLonglink(in, size, longlink)) {
+                    symlink = QFile::decodeName(longlink.constData());
+                } else {
+                    qCritical() << "Failed to read long link";
+                    return false;
+                }
+                break;
+            }
+            case TypeFlag::GNULongName: {
+                doNotReset = true;
+                QByteArray longlink;
+                if (readLonglink(in, size, longlink)) {
+                    name = QFile::decodeName(longlink.constData());
+                } else {
+                    qCritical() << "Failed to read long name";
+                    return false;
+                }
+                break;
+            }
+            case TypeFlag::Link:
+                /* fallthrough */
+            case TypeFlag::Symlink: {
+                auto fileName = FS::PathCombine(dst, name);
+                if (!FS::create_link(FS::PathCombine(QFileInfo(fileName).path(), symlink), fileName)()) {  // do not use symlinks
+                    qCritical() << "Can't create link for:" << fileName << " to:" << FS::PathCombine(QFileInfo(fileName).path(), symlink);
+                    return false;
+                }
+                FS::ensureFilePathExists(fileName);
+                QFile::setPermissions(fileName, QFile::Permissions(mode));
+                break;
+            }
+            case TypeFlag::Character:
+                /* fallthrough */
+            case TypeFlag::Block:
+                /* fallthrough */
+            case TypeFlag::FIFO:
+                /* fallthrough */
+            case TypeFlag::Contiguous:
+                /* fallthrough */
+            case TypeFlag::GlobalPosixHeader:
+                /* fallthrough */
+            case TypeFlag::ExtendedPosixHeader:
+                /* fallthrough */
+            default:
+                break;
+        }
+        if (!doNotReset) {
+            name.truncate(0);
+            symlink.truncate(0);
+        }
+        doNotReset = false;
+    }
+    return true;
+}
+
+bool GZTar::extract(QString src, QString dst)
+{
+    QuaGzipFile a(src);
+    if (!a.open(QIODevice::ReadOnly)) {
+        qCritical() << "Can't open tar file:" << src;
+        return false;
+    }
+    return Tar::extract(&a, dst);
+}

launcher/Untar.h

@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ *      Copyright 2013-2021 MultiMC Contributors
+ *
+ *      Licensed under the Apache License, Version 2.0 (the "License");
+ *      you may not use this file except in compliance with the License.
+ *      You may obtain a copy of the License at
+ *
+ *          http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *      Unless required by applicable law or agreed to in writing, software
+ *      distributed under the License is distributed on an "AS IS" BASIS,
+ *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *      See the License for the specific language governing permissions and
+ *      limitations under the License.
+ */
+#pragma once
+#include <QIODevice>
+
+// this is a hack used for the java downloader (feel free to remove it in favor of a library)
+// both extract functions will extract the first folder inside dest(disregarding the prefix)
+namespace Tar {
+bool extract(QIODevice* in, QString dst);
+}
+
+namespace GZTar {
+bool extract(QString src, QString dst);
+}

launcher/VersionProxyModel.cpp

@@ -114,10 +114,14 @@ QVariant VersionProxyModel::headerData(int section, Qt::Orientation orientation,
                 return tr("Branch");
             case Type:
                 return tr("Type");
-            case Architecture:
+            case CPUArchitecture:
                 return tr("Architecture");
             case Path:
                 return tr("Path");
+            case JavaName:
+                return tr("Java Name");
+            case JavaMajor:
+                return tr("Major Version");
             case Time:
                 return tr("Released");
         }
@@ -131,10 +135,14 @@ QVariant VersionProxyModel::headerData(int section, Qt::Orientation orientation,
                 return tr("The version's branch");
             case Type:
                 return tr("The version's type");
-            case Architecture:
+            case CPUArchitecture:
                 return tr("CPU Architecture");
             case Path:
                 return tr("Filesystem path to this version");
+            case JavaName:
+                return tr("The alternative name of the java version");
+            case JavaMajor:
+                return tr("The java major version");
             case Time:
                 return tr("Release date of this version");
         }
@@ -165,10 +173,14 @@ QVariant VersionProxyModel::data(const QModelIndex& index, int role) const
                     return sourceModel()->data(parentIndex, BaseVersionList::BranchRole);
                 case Type:
                     return sourceModel()->data(parentIndex, BaseVersionList::TypeRole);
-                case Architecture:
+                case CPUArchitecture:
-                    return sourceModel()->data(parentIndex, BaseVersionList::ArchitectureRole);
+                    return sourceModel()->data(parentIndex, BaseVersionList::CPUArchitectureRole);
                 case Path:
                     return sourceModel()->data(parentIndex, BaseVersionList::PathRole);
+                case JavaName:
+                    return sourceModel()->data(parentIndex, BaseVersionList::JavaNameRole);
+                case JavaMajor:
+                    return sourceModel()->data(parentIndex, BaseVersionList::JavaMajorRole);
                 case Time:
                     return sourceModel()->data(parentIndex, Meta::VersionList::TimeRole).toDate();
                 default:
@@ -308,12 +320,18 @@ void VersionProxyModel::setSourceModel(QAbstractItemModel* replacingRaw)
         m_columns.push_back(ParentVersion);
     }
     */
-    if (roles.contains(BaseVersionList::ArchitectureRole)) {
+    if (roles.contains(BaseVersionList::CPUArchitectureRole)) {
-        m_columns.push_back(Architecture);
+        m_columns.push_back(CPUArchitecture);
     }
     if (roles.contains(BaseVersionList::PathRole)) {
         m_columns.push_back(Path);
     }
+    if (roles.contains(BaseVersionList::JavaNameRole)) {
+        m_columns.push_back(JavaName);
+    }
+    if (roles.contains(BaseVersionList::JavaMajorRole)) {
+        m_columns.push_back(JavaMajor);
+    }
     if (roles.contains(Meta::VersionList::TimeRole)) {
         m_columns.push_back(Time);
     }

launcher/VersionProxyModel.h

@@ -9,7 +9,7 @@ class VersionFilterModel;
 class VersionProxyModel : public QAbstractProxyModel {
     Q_OBJECT
    public:
-    enum Column { Name, ParentVersion, Branch, Type, Architecture, Path, Time };
+    enum Column { Name, ParentVersion, Branch, Type, CPUArchitecture, Path, Time, JavaName, JavaMajor };
     using FilterMap = QHash<BaseVersionList::ModelRoles, std::shared_ptr<Filter>>;
 
    public:

launcher/java/JavaChecker.cpp

@@ -40,14 +40,15 @@
 #include <QMap>
 #include <QProcess>
 
-#include "Application.h"
 #include "Commandline.h"
 #include "FileSystem.h"
-#include "JavaUtils.h"
+#include "java/JavaUtils.h"
 
-JavaChecker::JavaChecker(QObject* parent) : QObject(parent) {}
+JavaChecker::JavaChecker(QString path, QString args, int minMem, int maxMem, int permGen, int id, QObject* parent)
+    : Task(parent), m_path(path), m_args(args), m_minMem(minMem), m_maxMem(maxMem), m_permGen(permGen), m_id(id)
+{}
 
-void JavaChecker::performCheck()
+void JavaChecker::executeTask()
 {
     QString checkerJar = JavaUtils::getJavaCheckPath();
 
@@ -72,7 +73,7 @@ void JavaChecker::performCheck()
     if (m_maxMem != 0) {
         args << QString("-Xmx%1m").arg(m_maxMem);
     }
-    if (m_permGen != 64) {
+    if (m_permGen != 64 && m_permGen != 0) {
         args << QString("-XX:PermSize=%1m").arg(m_permGen);
     }
 
@@ -115,11 +116,10 @@ void JavaChecker::finished(int exitcode, QProcess::ExitStatus status)
     QProcessPtr _process = process;
     process.reset();
 
-    JavaCheckResult result;
+    Result result = {
-    {
+        m_path,
-        result.path = m_path;
+        m_id,
-        result.id = m_id;
+    };
-    }
     result.errorLog = m_stderr;
     result.outLog = m_stdout;
     qDebug() << "STDOUT" << m_stdout;
@@ -127,8 +127,9 @@ void JavaChecker::finished(int exitcode, QProcess::ExitStatus status)
     qDebug() << "Java checker finished with status" << status << "exit code" << exitcode;
 
     if (status == QProcess::CrashExit || exitcode == 1) {
-        result.validity = JavaCheckResult::Validity::Errored;
+        result.validity = Result::Validity::Errored;
         emit checkFinished(result);
+        emitSucceeded();
         return;
     }
 
@@ -161,8 +162,9 @@ void JavaChecker::finished(int exitcode, QProcess::ExitStatus status)
     }
 
     if (!results.contains("os.arch") || !results.contains("java.version") || !results.contains("java.vendor") || !success) {
-        result.validity = JavaCheckResult::Validity::ReturnedInvalidData;
+        result.validity = Result::Validity::ReturnedInvalidData;
         emit checkFinished(result);
+        emitSucceeded();
         return;
     }
 
@@ -171,7 +173,7 @@ void JavaChecker::finished(int exitcode, QProcess::ExitStatus status)
     auto java_vendor = results["java.vendor"];
     bool is_64 = os_arch == "x86_64" || os_arch == "amd64" || os_arch == "aarch64" || os_arch == "arm64";
 
-    result.validity = JavaCheckResult::Validity::Valid;
+    result.validity = Result::Validity::Valid;
     result.is_64bit = is_64;
     result.mojangPlatform = is_64 ? "64" : "32";
     result.realPlatform = os_arch;
@@ -179,6 +181,7 @@ void JavaChecker::finished(int exitcode, QProcess::ExitStatus status)
     result.javaVendor = java_vendor;
     qDebug() << "Java checker succeeded.";
     emit checkFinished(result);
+    emitSucceeded();
 }
 
 void JavaChecker::error(QProcess::ProcessError err)
@@ -190,15 +193,9 @@ void JavaChecker::error(QProcess::ProcessError err)
         qDebug() << "Native environment:";
         qDebug() << QProcessEnvironment::systemEnvironment().toStringList();
         killTimer.stop();
-        JavaCheckResult result;
+        emit checkFinished({ m_path, m_id });
-        {
-            result.path = m_path;
-            result.id = m_id;
-        }
-
-        emit checkFinished(result);
-        return;
     }
+    emitSucceeded();
 }
 
 void JavaChecker::timeout()

launcher/java/JavaChecker.h

@@ -3,14 +3,19 @@
 #include <QTimer>
 #include <memory>
 
-#include "QObjectPtr.h"
-
 #include "JavaVersion.h"
+#include "QObjectPtr.h"
+#include "tasks/Task.h"
 
-class JavaChecker;
+class JavaChecker : public Task {
+    Q_OBJECT
+   public:
+    using QProcessPtr = shared_qobject_ptr<QProcess>;
+    using Ptr = shared_qobject_ptr<JavaChecker>;
 
-struct JavaCheckResult {
+    struct Result {
         QString path;
+        int id;
         QString mojangPlatform;
         QString realPlatform;
         JavaVersion javaVersion;
@@ -18,34 +23,31 @@ struct JavaCheckResult {
         QString outLog;
         QString errorLog;
         bool is_64bit = false;
-    int id;
         enum class Validity { Errored, ReturnedInvalidData, Valid } validity = Validity::Errored;
     };
 
-using QProcessPtr = shared_qobject_ptr<QProcess>;
+    explicit JavaChecker(QString path, QString args, int minMem = 0, int maxMem = 0, int permGen = 0, int id = 0, QObject* parent = 0);
-using JavaCheckerPtr = shared_qobject_ptr<JavaChecker>;
-class JavaChecker : public QObject {
-    Q_OBJECT
-   public:
-    explicit JavaChecker(QObject* parent = 0);
-    void performCheck();
-
-    QString m_path;
-    QString m_args;
-    int m_id = 0;
-    int m_minMem = 0;
-    int m_maxMem = 0;
-    int m_permGen = 64;
 
    signals:
-    void checkFinished(JavaCheckResult result);
+    void checkFinished(const Result& result);
+
+   protected:
+    virtual void executeTask() override;
 
    private:
     QProcessPtr process;
     QTimer killTimer;
     QString m_stdout;
     QString m_stderr;
-   public slots:
+
+    QString m_path;
+    QString m_args;
+    int m_minMem = 0;
+    int m_maxMem = 0;
+    int m_permGen = 64;
+    int m_id = 0;
+
+   private slots:
     void timeout();
     void finished(int exitcode, QProcess::ExitStatus);
     void error(QProcess::ProcessError);

launcher/java/JavaCheckerJob.cpp

@@ -1,41 +0,0 @@
-/* Copyright 2013-2021 MultiMC Contributors
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "JavaCheckerJob.h"
-
-#include <QDebug>
-
-void JavaCheckerJob::partFinished(JavaCheckResult result)
-{
-    num_finished++;
-    qDebug() << m_job_name.toLocal8Bit() << "progress:" << num_finished << "/" << javacheckers.size();
-    setProgress(num_finished, javacheckers.size());
-
-    javaresults.replace(result.id, result);
-
-    if (num_finished == javacheckers.size()) {
-        emitSucceeded();
-    }
-}
-
-void JavaCheckerJob::executeTask()
-{
-    qDebug() << m_job_name.toLocal8Bit() << " started.";
-    for (auto iter : javacheckers) {
-        javaresults.append(JavaCheckResult());
-        connect(iter.get(), &JavaChecker::checkFinished, this, &JavaCheckerJob::partFinished);
-        iter->performCheck();
-    }
-}

launcher/java/JavaCheckerJob.h

@@ -1,56 +0,0 @@
-/* Copyright 2013-2021 MultiMC Contributors
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#pragma once
-
-#include <QtNetwork>
-#include "JavaChecker.h"
-#include "tasks/Task.h"
-
-class JavaCheckerJob;
-using JavaCheckerJobPtr = shared_qobject_ptr<JavaCheckerJob>;
-
-// FIXME: this just seems horribly redundant
-class JavaCheckerJob : public Task {
-    Q_OBJECT
-   public:
-    explicit JavaCheckerJob(QString job_name) : Task(), m_job_name(job_name) {};
-    virtual ~JavaCheckerJob() {};
-
-    bool addJavaCheckerAction(JavaCheckerPtr base)
-    {
-        javacheckers.append(base);
-        // if this is already running, the action needs to be started right away!
-        if (isRunning()) {
-            setProgress(num_finished, javacheckers.size());
-            connect(base.get(), &JavaChecker::checkFinished, this, &JavaCheckerJob::partFinished);
-            base->performCheck();
-        }
-        return true;
-    }
-    QList<JavaCheckResult> getResults() { return javaresults; }
-
-   private slots:
-    void partFinished(JavaCheckResult result);
-
-   protected:
-    virtual void executeTask() override;
-
-   private:
-    QString m_job_name;
-    QList<JavaCheckerPtr> javacheckers;
-    QList<JavaCheckResult> javaresults;
-    int num_finished = 0;
-};

launcher/java/JavaInstall.cpp

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-3.0-only
 /*
  *  Prism Launcher - Minecraft Launcher
- *  Copyright (c) 2023 Trial97 <alexandru.tripon97@gmail.com>
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
  *
  *  This program is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by

launcher/java/JavaInstall.h

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-3.0-only
 /*
  *  Prism Launcher - Minecraft Launcher
- *  Copyright (c) 2023 Trial97 <alexandru.tripon97@gmail.com>
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
  *
  *  This program is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -40,6 +40,7 @@ struct JavaInstall : public BaseVersion {
     QString arch;
     QString path;
     bool recommended = false;
+    bool is_64bit = false;
 };
 
 using JavaInstallPtr = std::shared_ptr<JavaInstall>;

launcher/java/JavaInstallList.cpp

@@ -38,13 +38,17 @@
 #include <QtXml>
 
 #include <QDebug>
+#include <algorithm>
 
-#include "java/JavaCheckerJob.h"
+#include "Application.h"
+#include "java/JavaChecker.h"
 #include "java/JavaInstallList.h"
 #include "java/JavaUtils.h"
-#include "minecraft/VersionFilterData.h"
+#include "tasks/ConcurrentTask.h"
 
-JavaInstallList::JavaInstallList(QObject* parent) : BaseVersionList(parent) {}
+JavaInstallList::JavaInstallList(QObject* parent, bool onlyManagedVersions)
+    : BaseVersionList(parent), m_only_managed_versions(onlyManagedVersions)
+{}
 
 Task::Ptr JavaInstallList::getLoadTask()
 {
@@ -55,7 +59,7 @@ Task::Ptr JavaInstallList::getLoadTask()
 Task::Ptr JavaInstallList::getCurrentTask()
 {
     if (m_status == Status::InProgress) {
-        return m_loadTask;
+        return m_load_task;
     }
     return nullptr;
 }
@@ -64,8 +68,8 @@ void JavaInstallList::load()
 {
     if (m_status != Status::InProgress) {
         m_status = Status::InProgress;
-        m_loadTask.reset(new JavaListLoadTask(this));
+        m_load_task.reset(new JavaListLoadTask(this, m_only_managed_versions));
-        m_loadTask->start();
+        m_load_task->start();
     }
 }
 
@@ -106,7 +110,7 @@ QVariant JavaInstallList::data(const QModelIndex& index, int role) const
             return version->recommended;
         case PathRole:
             return version->path;
-        case ArchitectureRole:
+        case CPUArchitectureRole:
             return version->arch;
         default:
             return QVariant();
@@ -115,7 +119,7 @@ QVariant JavaInstallList::data(const QModelIndex& index, int role) const
 
 BaseVersionList::RoleList JavaInstallList::providesRoles() const
 {
-    return { VersionPointerRole, VersionIdRole, VersionRole, RecommendedRole, PathRole, ArchitectureRole };
+    return { VersionPointerRole, VersionIdRole, VersionRole, RecommendedRole, PathRole, CPUArchitectureRole };
 }
 
 void JavaInstallList::updateListData(QList<BaseVersion::Ptr> versions)
@@ -129,7 +133,7 @@ void JavaInstallList::updateListData(QList<BaseVersion::Ptr> versions)
     }
     endResetModel();
     m_status = Status::Done;
-    m_loadTask.reset();
+    m_load_task.reset();
 }
 
 bool sortJavas(BaseVersion::Ptr left, BaseVersion::Ptr right)
@@ -146,35 +150,30 @@ void JavaInstallList::sortVersions()
     endResetModel();
 }
 
-JavaListLoadTask::JavaListLoadTask(JavaInstallList* vlist) : Task()
+JavaListLoadTask::JavaListLoadTask(JavaInstallList* vlist, bool onlyManagedVersions) : Task(), m_only_managed_versions(onlyManagedVersions)
 {
     m_list = vlist;
-    m_currentRecommended = NULL;
+    m_current_recommended = NULL;
 }
 
-JavaListLoadTask::~JavaListLoadTask() {}
-
 void JavaListLoadTask::executeTask()
 {
     setStatus(tr("Detecting Java installations..."));
 
     JavaUtils ju;
-    QList<QString> candidate_paths = ju.FindJavaPaths();
+    QList<QString> candidate_paths = m_only_managed_versions ? getPrismJavaBundle() : ju.FindJavaPaths();
 
-    m_job.reset(new JavaCheckerJob("Java detection"));
+    ConcurrentTask::Ptr job(new ConcurrentTask(this, "Java detection", APPLICATION->settings()->get("NumberOfConcurrentTasks").toInt()));
+    m_job.reset(job);
     connect(m_job.get(), &Task::finished, this, &JavaListLoadTask::javaCheckerFinished);
     connect(m_job.get(), &Task::progress, this, &Task::setProgress);
 
     qDebug() << "Probing the following Java paths: ";
     int id = 0;
     for (QString candidate : candidate_paths) {
-        qDebug() << " " << candidate;
+        auto checker = new JavaChecker(candidate, "", 0, 0, 0, id, this);
-
+        connect(checker, &JavaChecker::checkFinished, [this](const JavaChecker::Result& result) { m_results << result; });
-        auto candidate_checker = new JavaChecker();
+        job->addTask(Task::Ptr(checker));
-        candidate_checker->m_path = candidate;
-        candidate_checker->m_id = id;
-        m_job->addJavaCheckerAction(JavaCheckerPtr(candidate_checker));
-
         id++;
     }
 
@@ -184,16 +183,17 @@ void JavaListLoadTask::executeTask()
 void JavaListLoadTask::javaCheckerFinished()
 {
     QList<JavaInstallPtr> candidates;
-    auto results = m_job->getResults();
+    std::sort(m_results.begin(), m_results.end(), [](const JavaChecker::Result& a, const JavaChecker::Result& b) { return a.id < b.id; });
 
     qDebug() << "Found the following valid Java installations:";
-    for (JavaCheckResult result : results) {
+    for (auto result : m_results) {
-        if (result.validity == JavaCheckResult::Validity::Valid) {
+        if (result.validity == JavaChecker::Result::Validity::Valid) {
             JavaInstallPtr javaVersion(new JavaInstall());
 
             javaVersion->id = result.javaVersion;
             javaVersion->arch = result.realPlatform;
             javaVersion->path = result.path;
+            javaVersion->is_64bit = result.is_64bit;
             candidates.append(javaVersion);
 
             qDebug() << " " << javaVersion->id.toString() << javaVersion->arch << javaVersion->path;

launcher/java/JavaInstallList.h

@@ -19,9 +19,9 @@
 #include <QObject>
 
 #include "BaseVersionList.h"
+#include "java/JavaChecker.h"
 #include "tasks/Task.h"
 
-#include "JavaCheckerJob.h"
 #include "JavaInstall.h"
 
 #include "QObjectPtr.h"
@@ -33,7 +33,7 @@ class JavaInstallList : public BaseVersionList {
     enum class Status { NotDone, InProgress, Done };
 
    public:
-    explicit JavaInstallList(QObject* parent = 0);
+    explicit JavaInstallList(QObject* parent = 0, bool onlyManagedVersions = false);
 
     [[nodiscard]] Task::Ptr getLoadTask() override;
     bool isLoaded() override;
@@ -53,23 +53,27 @@ class JavaInstallList : public BaseVersionList {
 
    protected:
     Status m_status = Status::NotDone;
-    shared_qobject_ptr<JavaListLoadTask> m_loadTask;
+    shared_qobject_ptr<JavaListLoadTask> m_load_task;
     QList<BaseVersion::Ptr> m_vlist;
+    bool m_only_managed_versions;
 };
 
 class JavaListLoadTask : public Task {
     Q_OBJECT
 
    public:
-    explicit JavaListLoadTask(JavaInstallList* vlist);
+    explicit JavaListLoadTask(JavaInstallList* vlist, bool onlyManagedVersions = false);
-    virtual ~JavaListLoadTask();
+    virtual ~JavaListLoadTask() = default;
 
+   protected:
     void executeTask() override;
    public slots:
     void javaCheckerFinished();
 
    protected:
-    shared_qobject_ptr<JavaCheckerJob> m_job;
+    Task::Ptr m_job;
     JavaInstallList* m_list;
-    JavaInstall* m_currentRecommended;
+    JavaInstall* m_current_recommended;
+    QList<JavaChecker::Result> m_results;
+    bool m_only_managed_versions;
 };

launcher/java/JavaMetadata.cpp

@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "java/JavaMetadata.h"
+
+#include <memory>
+
+#include "Json.h"
+#include "StringUtils.h"
+#include "java/JavaVersion.h"
+#include "minecraft/ParseUtils.h"
+
+namespace Java {
+
+DownloadType parseDownloadType(QString javaDownload)
+{
+    if (javaDownload == "manifest")
+        return DownloadType::Manifest;
+    else if (javaDownload == "archive")
+        return DownloadType::Archive;
+    else
+        return DownloadType::Unknown;
+}
+QString downloadTypeToString(DownloadType javaDownload)
+{
+    switch (javaDownload) {
+        case DownloadType::Manifest:
+            return "manifest";
+        case DownloadType::Archive:
+            return "archive";
+        case DownloadType::Unknown:
+            break;
+    }
+    return "unknown";
+}
+MetadataPtr parseJavaMeta(const QJsonObject& in)
+{
+    auto meta = std::make_shared<Metadata>();
+
+    meta->m_name = Json::ensureString(in, "name", "");
+    meta->vendor = Json::ensureString(in, "vendor", "");
+    meta->url = Json::ensureString(in, "url", "");
+    meta->releaseTime = timeFromS3Time(Json::ensureString(in, "releaseTime", ""));
+    meta->downloadType = parseDownloadType(Json::ensureString(in, "downloadType", ""));
+    meta->packageType = Json::ensureString(in, "packageType", "");
+    meta->runtimeOS = Json::ensureString(in, "runtimeOS", "unknown");
+
+    if (in.contains("checksum")) {
+        auto obj = Json::requireObject(in, "checksum");
+        meta->checksumHash = Json::ensureString(obj, "hash", "");
+        meta->checksumType = Json::ensureString(obj, "type", "");
+    }
+
+    if (in.contains("version")) {
+        auto obj = Json::requireObject(in, "version");
+        auto name = Json::ensureString(obj, "name", "");
+        auto major = Json::ensureInteger(obj, "major", 0);
+        auto minor = Json::ensureInteger(obj, "minor", 0);
+        auto security = Json::ensureInteger(obj, "security", 0);
+        auto build = Json::ensureInteger(obj, "build", 0);
+        meta->version = JavaVersion(major, minor, security, build, name);
+    }
+    return meta;
+}
+
+bool Metadata::operator<(const Metadata& rhs)
+{
+    auto id = version;
+    if (id < rhs.version) {
+        return true;
+    }
+    if (id > rhs.version) {
+        return false;
+    }
+    auto date = releaseTime;
+    if (date < rhs.releaseTime) {
+        return true;
+    }
+    if (date > rhs.releaseTime) {
+        return false;
+    }
+    return StringUtils::naturalCompare(m_name, rhs.m_name, Qt::CaseInsensitive) < 0;
+}
+
+bool Metadata::operator==(const Metadata& rhs)
+{
+    return version == rhs.version && m_name == rhs.m_name;
+}
+
+bool Metadata::operator>(const Metadata& rhs)
+{
+    return (!operator<(rhs)) && (!operator==(rhs));
+}
+
+bool Metadata::operator<(BaseVersion& a)
+{
+    try {
+        return operator<(dynamic_cast<Metadata&>(a));
+    } catch (const std::bad_cast& e) {
+        return BaseVersion::operator<(a);
+    }
+}
+
+bool Metadata::operator>(BaseVersion& a)
+{
+    try {
+        return operator>(dynamic_cast<Metadata&>(a));
+    } catch (const std::bad_cast& e) {
+        return BaseVersion::operator>(a);
+    }
+}
+
+}  // namespace Java

launcher/java/JavaMetadata.h

@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <QDateTime>
+#include <QJsonObject>
+#include <QString>
+
+#include <memory>
+
+#include "BaseVersion.h"
+#include "java/JavaVersion.h"
+
+namespace Java {
+
+enum class DownloadType { Manifest, Archive, Unknown };
+
+class Metadata : public BaseVersion {
+   public:
+    virtual QString descriptor() override { return version.toString(); }
+
+    virtual QString name() override { return m_name; }
+
+    virtual QString typeString() const override { return vendor; }
+
+    virtual bool operator<(BaseVersion& a) override;
+    virtual bool operator>(BaseVersion& a) override;
+    bool operator<(const Metadata& rhs);
+    bool operator==(const Metadata& rhs);
+    bool operator>(const Metadata& rhs);
+
+    QString m_name;
+    QString vendor;
+    QString url;
+    QDateTime releaseTime;
+    QString checksumType;
+    QString checksumHash;
+    DownloadType downloadType;
+    QString packageType;
+    JavaVersion version;
+    QString runtimeOS;
+};
+using MetadataPtr = std::shared_ptr<Metadata>;
+
+DownloadType parseDownloadType(QString javaDownload);
+QString downloadTypeToString(DownloadType javaDownload);
+MetadataPtr parseJavaMeta(const QJsonObject& libObj);
+
+}  // namespace Java

launcher/java/JavaUtils.cpp

@@ -347,6 +347,7 @@ QList<QString> JavaUtils::FindJavaPaths()
     }
 
     candidates.append(getMinecraftJavaBundle());
+    candidates.append(getPrismJavaBundle());
     candidates = addJavasFromEnv(candidates);
     candidates.removeDuplicates();
     return candidates;
@@ -391,6 +392,7 @@ QList<QString> JavaUtils::FindJavaPaths()
     }
 
     javas.append(getMinecraftJavaBundle());
+    javas.append(getPrismJavaBundle());
     javas = addJavasFromEnv(javas);
     javas.removeDuplicates();
     return javas;
@@ -454,6 +456,7 @@ QList<QString> JavaUtils::FindJavaPaths()
     scanJavaDirs(FS::PathCombine(home, ".gradle/jdks"));
 
     javas.append(getMinecraftJavaBundle());
+    javas.append(getPrismJavaBundle());
     javas = addJavasFromEnv(javas);
     javas.removeDuplicates();
     return javas;
@@ -467,6 +470,8 @@ QList<QString> JavaUtils::FindJavaPaths()
     javas.append(this->GetDefaultJava()->path);
 
     javas.append(getMinecraftJavaBundle());
+    javas.append(getPrismJavaBundle());
+    javas.removeDuplicates();
     return addJavasFromEnv(javas);
 }
 #endif
@@ -478,12 +483,10 @@ QString JavaUtils::getJavaCheckPath()
 
 QStringList getMinecraftJavaBundle()
 {
-    QString executable = "java";
     QStringList processpaths;
 #if defined(Q_OS_OSX)
     processpaths << FS::PathCombine(QDir::homePath(), FS::PathCombine("Library", "Application Support", "minecraft", "runtime"));
 #elif defined(Q_OS_WIN32)
-    executable += "w.exe";
 
     auto appDataPath = QProcessEnvironment::systemEnvironment().value("APPDATA", "");
     processpaths << FS::PathCombine(QFileInfo(appDataPath).absoluteFilePath(), ".minecraft", "runtime");
@@ -508,7 +511,7 @@ QStringList getMinecraftJavaBundle()
         auto binFound = false;
         for (auto& entry : entries) {
             if (entry.baseName() == "bin") {
-                javas.append(FS::PathCombine(entry.canonicalFilePath(), executable));
+                javas.append(FS::PathCombine(entry.canonicalFilePath(), JavaUtils::javaExecutable));
                 binFound = true;
                 break;
             }
@@ -521,3 +524,33 @@ QStringList getMinecraftJavaBundle()
     }
     return javas;
 }
+
+#if defined(Q_OS_WIN32)
+const QString JavaUtils::javaExecutable = "javaw.exe";
+#else
+const QString JavaUtils::javaExecutable = "java";
+#endif
+
+QStringList getPrismJavaBundle()
+{
+    QList<QString> javas;
+
+    auto scanDir = [&](QString prefix) {
+        javas.append(FS::PathCombine(prefix, "jre", "bin", JavaUtils::javaExecutable));
+        javas.append(FS::PathCombine(prefix, "bin", JavaUtils::javaExecutable));
+        javas.append(FS::PathCombine(prefix, JavaUtils::javaExecutable));
+    };
+    auto scanJavaDir = [&](const QString& dirPath) {
+        QDir dir(dirPath);
+        if (!dir.exists())
+            return;
+        auto entries = dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
+        for (auto& entry : entries) {
+            scanDir(entry.canonicalFilePath());
+        }
+    };
+
+    scanJavaDir(APPLICATION->javaPath());
+
+    return javas;
+}

launcher/java/JavaUtils.h

@@ -15,10 +15,9 @@
 
 #pragma once
 
+#include <QProcess>
 #include <QStringList>
-
+#include "java/JavaInstall.h"
-#include "JavaChecker.h"
-#include "JavaInstallList.h"
 
 #ifdef Q_OS_WIN
 #include <windows.h>
@@ -27,6 +26,7 @@
 QString stripVariableEntries(QString name, QString target, QString remove);
 QProcessEnvironment CleanEnviroment();
 QStringList getMinecraftJavaBundle();
+QStringList getPrismJavaBundle();
 
 class JavaUtils : public QObject {
     Q_OBJECT
@@ -42,4 +42,5 @@ class JavaUtils : public QObject {
 #endif
 
     static QString getJavaCheckPath();
+    static const QString javaExecutable;
 };

launcher/java/JavaVersion.cpp

@@ -43,12 +43,12 @@ QString JavaVersion::toString() const
     return m_string;
 }
 
-bool JavaVersion::requiresPermGen()
+bool JavaVersion::requiresPermGen() const
 {
     return !m_parseable || m_major < 8;
 }
 
-bool JavaVersion::isModular()
+bool JavaVersion::isModular() const
 {
     return m_parseable && m_major >= 9;
 }
@@ -59,12 +59,6 @@ bool JavaVersion::operator<(const JavaVersion& rhs)
         auto major = m_major;
         auto rmajor = rhs.m_major;
 
-        // HACK: discourage using java 9
-        if (major > 8)
-            major = -major;
-        if (rmajor > 8)
-            rmajor = -rmajor;
-
         if (major < rmajor)
             return true;
         if (major > rmajor)
@@ -109,3 +103,24 @@ bool JavaVersion::operator>(const JavaVersion& rhs)
 {
     return (!operator<(rhs)) && (!operator==(rhs));
 }
+
+JavaVersion::JavaVersion(int major, int minor, int security, int build, QString name)
+    : m_major(major), m_minor(minor), m_security(security), m_name(name), m_parseable(true)
+{
+    QStringList versions;
+    if (build != 0) {
+        m_prerelease = QString::number(build);
+        versions.push_front(m_prerelease);
+    }
+    if (m_security != 0)
+        versions.push_front(QString::number(m_security));
+    else if (!versions.isEmpty())
+        versions.push_front("0");
+
+    if (m_minor != 0)
+        versions.push_front(QString::number(m_minor));
+    else if (!versions.isEmpty())
+        versions.push_front("0");
+    versions.push_front(QString::number(m_major));
+    m_string = versions.join(".");
+}

launcher/java/JavaVersion.h

@@ -16,6 +16,7 @@ class JavaVersion {
    public:
     JavaVersion() {}
     JavaVersion(const QString& rhs);
+    JavaVersion(int major, int minor, int security, int build = 0, QString name = "");
 
     JavaVersion& operator=(const QString& rhs);
 
@@ -23,21 +24,24 @@ class JavaVersion {
     bool operator==(const JavaVersion& rhs);
     bool operator>(const JavaVersion& rhs);
 
-    bool requiresPermGen();
+    bool requiresPermGen() const;
 
-    bool isModular();
+    bool isModular() const;
 
     QString toString() const;
 
-    int major() { return m_major; }
+    int major() const { return m_major; }
-    int minor() { return m_minor; }
+    int minor() const { return m_minor; }
-    int security() { return m_security; }
+    int security() const { return m_security; }
+    QString build() const { return m_prerelease; }
+    QString name() const { return m_name; }
 
    private:
     QString m_string;
     int m_major = 0;
     int m_minor = 0;
     int m_security = 0;
+    QString m_name = "";
     bool m_parseable = false;
     QString m_prerelease;
 };

launcher/java/download/ArchiveDownloadTask.cpp

@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#include "java/download/ArchiveDownloadTask.h"
+#include <quazip.h>
+#include <memory>
+#include "MMCZip.h"
+
+#include "Application.h"
+#include "Untar.h"
+#include "net/ChecksumValidator.h"
+#include "net/NetJob.h"
+#include "tasks/Task.h"
+
+namespace Java {
+ArchiveDownloadTask::ArchiveDownloadTask(QUrl url, QString final_path, QString checksumType, QString checksumHash)
+    : m_url(url), m_final_path(final_path), m_checksum_type(checksumType), m_checksum_hash(checksumHash)
+{}
+
+void ArchiveDownloadTask::executeTask()
+{
+    // JRE found ! download the zip
+    setStatus(tr("Downloading Java"));
+
+    MetaEntryPtr entry = APPLICATION->metacache()->resolveEntry("java", m_url.fileName());
+
+    auto download = makeShared<NetJob>(QString("JRE::DownloadJava"), APPLICATION->network());
+    auto action = Net::Download::makeCached(m_url, entry);
+    if (!m_checksum_hash.isEmpty() && !m_checksum_type.isEmpty()) {
+        auto hashType = QCryptographicHash::Algorithm::Sha1;
+        if (m_checksum_type == "sha256") {
+            hashType = QCryptographicHash::Algorithm::Sha256;
+        }
+        action->addValidator(new Net::ChecksumValidator(hashType, QByteArray::fromHex(m_checksum_hash.toUtf8())));
+    }
+    download->addNetAction(action);
+    auto fullPath = entry->getFullPath();
+
+    connect(download.get(), &Task::failed, this, &ArchiveDownloadTask::emitFailed);
+    connect(download.get(), &Task::progress, this, &ArchiveDownloadTask::setProgress);
+    connect(download.get(), &Task::stepProgress, this, &ArchiveDownloadTask::propagateStepProgress);
+    connect(download.get(), &Task::status, this, &ArchiveDownloadTask::setStatus);
+    connect(download.get(), &Task::details, this, &ArchiveDownloadTask::setDetails);
+    connect(download.get(), &Task::succeeded, [this, fullPath] {
+        // This should do all of the extracting and creating folders
+        extractJava(fullPath);
+    });
+    m_task = download;
+    m_task->start();
+}
+
+void ArchiveDownloadTask::extractJava(QString input)
+{
+    setStatus(tr("Extracting java"));
+    if (input.endsWith("tar")) {
+        setStatus(tr("Extracting Java (Progress is not reported for tar archives)"));
+        QFile in(input);
+        if (!in.open(QFile::ReadOnly)) {
+            emitFailed(tr("Unable to open supplied tar file."));
+            return;
+        }
+        if (!Tar::extract(&in, QDir(m_final_path).absolutePath())) {
+            emitFailed(tr("Unable to extract supplied tar file."));
+            return;
+        }
+        emitSucceeded();
+        return;
+    } else if (input.endsWith("tar.gz") || input.endsWith("taz") || input.endsWith("tgz")) {
+        setStatus(tr("Extracting Java (Progress is not reported for tar archives)"));
+        if (!GZTar::extract(input, QDir(m_final_path).absolutePath())) {
+            emitFailed(tr("Unable to extract supplied tar file."));
+            return;
+        }
+        emitSucceeded();
+        return;
+    } else if (input.endsWith("zip")) {
+        auto zip = std::make_shared<QuaZip>(input);
+        if (!zip->open(QuaZip::mdUnzip)) {
+            emitFailed(tr("Unable to open supplied zip file."));
+            return;
+        }
+        auto files = zip->getFileNameList();
+        if (files.isEmpty()) {
+            emitFailed(tr("No files were found in the supplied zip file,"));
+            return;
+        }
+        m_task = makeShared<MMCZip::ExtractZipTask>(zip, m_final_path, files[0]);
+
+        auto progressStep = std::make_shared<TaskStepProgress>();
+        connect(m_task.get(), &Task::finished, this, [this, progressStep] {
+            progressStep->state = TaskStepState::Succeeded;
+            stepProgress(*progressStep);
+        });
+
+        connect(m_task.get(), &Task::succeeded, this, &ArchiveDownloadTask::emitSucceeded);
+        connect(m_task.get(), &Task::aborted, this, &ArchiveDownloadTask::emitAborted);
+        connect(m_task.get(), &Task::failed, this, [this, progressStep](QString reason) {
+            progressStep->state = TaskStepState::Failed;
+            stepProgress(*progressStep);
+            emitFailed(reason);
+        });
+        connect(m_task.get(), &Task::stepProgress, this, &ArchiveDownloadTask::propagateStepProgress);
+
+        connect(m_task.get(), &Task::progress, this, [this, progressStep](qint64 current, qint64 total) {
+            progressStep->update(current, total);
+            stepProgress(*progressStep);
+        });
+        connect(m_task.get(), &Task::status, this, [this, progressStep](QString status) {
+            progressStep->status = status;
+            stepProgress(*progressStep);
+        });
+        m_task->start();
+        return;
+    }
+
+    emitFailed(tr("Could not determine archive type!"));
+}
+
+bool ArchiveDownloadTask::abort()
+{
+    auto aborted = canAbort();
+    if (m_task)
+        aborted = m_task->abort();
+    emitAborted();
+    return aborted;
+};
+}  // namespace Java

launcher/java/download/ArchiveDownloadTask.h

@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <QUrl>
+#include "tasks/Task.h"
+
+namespace Java {
+class ArchiveDownloadTask : public Task {
+    Q_OBJECT
+   public:
+    ArchiveDownloadTask(QUrl url, QString final_path, QString checksumType = "", QString checksumHash = "");
+    virtual ~ArchiveDownloadTask() = default;
+
+    [[nodiscard]] bool canAbort() const override { return true; }
+    void executeTask() override;
+    virtual bool abort() override;
+
+   private slots:
+    void extractJava(QString input);
+
+   protected:
+    QUrl m_url;
+    QString m_final_path;
+    QString m_checksum_type;
+    QString m_checksum_hash;
+    Task::Ptr m_task;
+};
+}  // namespace Java

launcher/java/download/ManifestDownloadTask.cpp

@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#include "java/download/ManifestDownloadTask.h"
+
+#include "Application.h"
+#include "FileSystem.h"
+#include "Json.h"
+#include "net/ChecksumValidator.h"
+#include "net/NetJob.h"
+
+struct File {
+    QString path;
+    QString url;
+    QByteArray hash;
+    bool isExec;
+};
+
+namespace Java {
+ManifestDownloadTask::ManifestDownloadTask(QUrl url, QString final_path, QString checksumType, QString checksumHash)
+    : m_url(url), m_final_path(final_path), m_checksum_type(checksumType), m_checksum_hash(checksumHash)
+{}
+
+void ManifestDownloadTask::executeTask()
+{
+    setStatus(tr("Downloading Java"));
+    auto download = makeShared<NetJob>(QString("JRE::DownloadJava"), APPLICATION->network());
+    auto files = std::make_shared<QByteArray>();
+
+    auto action = Net::Download::makeByteArray(m_url, files);
+    if (!m_checksum_hash.isEmpty() && !m_checksum_type.isEmpty()) {
+        auto hashType = QCryptographicHash::Algorithm::Sha1;
+        if (m_checksum_type == "sha256") {
+            hashType = QCryptographicHash::Algorithm::Sha256;
+        }
+        action->addValidator(new Net::ChecksumValidator(hashType, QByteArray::fromHex(m_checksum_hash.toUtf8())));
+    }
+    download->addNetAction(action);
+
+    connect(download.get(), &Task::failed, this, &ManifestDownloadTask::emitFailed);
+    connect(download.get(), &Task::progress, this, &ManifestDownloadTask::setProgress);
+    connect(download.get(), &Task::stepProgress, this, &ManifestDownloadTask::propagateStepProgress);
+    connect(download.get(), &Task::status, this, &ManifestDownloadTask::setStatus);
+    connect(download.get(), &Task::details, this, &ManifestDownloadTask::setDetails);
+
+    connect(download.get(), &Task::succeeded, [files, this] {
+        QJsonParseError parse_error{};
+        QJsonDocument doc = QJsonDocument::fromJson(*files, &parse_error);
+        if (parse_error.error != QJsonParseError::NoError) {
+            qWarning() << "Error while parsing JSON response at " << parse_error.offset << ". Reason: " << parse_error.errorString();
+            qWarning() << *files;
+            emitFailed(parse_error.errorString());
+            return;
+        }
+        downloadJava(doc);
+    });
+    m_task = download;
+    m_task->start();
+}
+
+void ManifestDownloadTask::downloadJava(const QJsonDocument& doc)
+{
+    // valid json doc, begin making jre spot
+    FS::ensureFolderPathExists(m_final_path);
+    std::vector<File> toDownload;
+    auto list = Json::ensureObject(Json::ensureObject(doc.object()), "files");
+    for (const auto& paths : list.keys()) {
+        auto file = FS::PathCombine(m_final_path, paths);
+
+        const QJsonObject& meta = Json::ensureObject(list, paths);
+        auto type = Json::ensureString(meta, "type");
+        if (type == "directory") {
+            FS::ensureFolderPathExists(file);
+        } else if (type == "link") {
+            // this is linux only !
+            auto path = Json::ensureString(meta, "target");
+            if (!path.isEmpty()) {
+                auto target = FS::PathCombine(file, "../" + path);
+                QFile(target).link(file);
+            }
+        } else if (type == "file") {
+            // TODO download compressed version if it exists ?
+            auto raw = Json::ensureObject(Json::ensureObject(meta, "downloads"), "raw");
+            auto isExec = Json::ensureBoolean(meta, "executable", false);
+            auto url = Json::ensureString(raw, "url");
+            if (!url.isEmpty() && QUrl(url).isValid()) {
+                auto f = File{ file, url, QByteArray::fromHex(Json::ensureString(raw, "sha1").toLatin1()), isExec };
+                toDownload.push_back(f);
+            }
+        }
+    }
+    auto elementDownload = makeShared<NetJob>("JRE::FileDownload", APPLICATION->network());
+    for (const auto& file : toDownload) {
+        auto dl = Net::Download::makeFile(file.url, file.path);
+        if (!file.hash.isEmpty()) {
+            dl->addValidator(new Net::ChecksumValidator(QCryptographicHash::Sha1, file.hash));
+        }
+        if (file.isExec) {
+            connect(dl.get(), &Net::Download::succeeded,
+                    [file] { QFile(file.path).setPermissions(QFile(file.path).permissions() | QFileDevice::Permissions(0x1111)); });
+        }
+        elementDownload->addNetAction(dl);
+    }
+
+    connect(elementDownload.get(), &Task::failed, this, &ManifestDownloadTask::emitFailed);
+    connect(elementDownload.get(), &Task::progress, this, &ManifestDownloadTask::setProgress);
+    connect(elementDownload.get(), &Task::stepProgress, this, &ManifestDownloadTask::propagateStepProgress);
+    connect(elementDownload.get(), &Task::status, this, &ManifestDownloadTask::setStatus);
+    connect(elementDownload.get(), &Task::details, this, &ManifestDownloadTask::setDetails);
+
+    connect(elementDownload.get(), &Task::succeeded, this, &ManifestDownloadTask::emitSucceeded);
+    m_task = elementDownload;
+    m_task->start();
+}
+
+bool ManifestDownloadTask::abort()
+{
+    auto aborted = canAbort();
+    if (m_task)
+        aborted = m_task->abort();
+    emitAborted();
+    return aborted;
+};
+}  // namespace Java

launcher/java/download/ManifestDownloadTask.h

@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <QUrl>
+#include "tasks/Task.h"
+
+namespace Java {
+
+class ManifestDownloadTask : public Task {
+    Q_OBJECT
+   public:
+    ManifestDownloadTask(QUrl url, QString final_path, QString checksumType = "", QString checksumHash = "");
+    virtual ~ManifestDownloadTask() = default;
+
+    [[nodiscard]] bool canAbort() const override { return true; }
+    void executeTask() override;
+    virtual bool abort() override;
+
+   private slots:
+    void downloadJava(const QJsonDocument& doc);
+
+   protected:
+    QUrl m_url;
+    QString m_final_path;
+    QString m_checksum_type;
+    QString m_checksum_hash;
+    Task::Ptr m_task;
+};
+}  // namespace Java

launcher/launch/steps/CheckJava.cpp

@@ -37,6 +37,7 @@
 #include <FileSystem.h>
 #include <launch/LaunchTask.h>
 #include <sys.h>
+#include <QCryptographicHash>
 #include <QFileInfo>
 #include <QStandardPaths>
 #include "java/JavaUtils.h"
@@ -93,11 +94,10 @@ void CheckJava::executeTask()
     // if timestamps are not the same, or something is missing, check!
     if (m_javaSignature != storedSignature || storedVersion.size() == 0 || storedArchitecture.size() == 0 ||
         storedRealArchitecture.size() == 0 || storedVendor.size() == 0) {
-        m_JavaChecker.reset(new JavaChecker);
+        m_JavaChecker.reset(new JavaChecker(realJavaPath, "", 0, 0, 0, 0, this));
         emit logLine(QString("Checking Java version..."), MessageLevel::Launcher);
         connect(m_JavaChecker.get(), &JavaChecker::checkFinished, this, &CheckJava::checkJavaFinished);
-        m_JavaChecker->m_path = realJavaPath;
+        m_JavaChecker->start();
-        m_JavaChecker->performCheck();
         return;
     } else {
         auto verString = instance->settings()->get("JavaVersion").toString();
@@ -109,10 +109,10 @@ void CheckJava::executeTask()
     emitSucceeded();
 }
 
-void CheckJava::checkJavaFinished(JavaCheckResult result)
+void CheckJava::checkJavaFinished(const JavaChecker::Result& result)
 {
     switch (result.validity) {
-        case JavaCheckResult::Validity::Errored: {
+        case JavaChecker::Result::Validity::Errored: {
             // Error message displayed if java can't start
             emit logLine(QString("Could not start java:"), MessageLevel::Error);
             emit logLines(result.errorLog.split('\n'), MessageLevel::Error);
@@ -120,14 +120,14 @@ void CheckJava::checkJavaFinished(JavaCheckResult result)
             emitFailed(QString("Could not start java!"));
             return;
         }
-        case JavaCheckResult::Validity::ReturnedInvalidData: {
+        case JavaChecker::Result::Validity::ReturnedInvalidData: {
             emit logLine(QString("Java checker returned some invalid data we don't understand:"), MessageLevel::Error);
             emit logLines(result.outLog.split('\n'), MessageLevel::Warning);
             emit logLine("\nMinecraft might not start properly.", MessageLevel::Launcher);
             emitSucceeded();
             return;
         }
-        case JavaCheckResult::Validity::Valid: {
+        case JavaChecker::Result::Validity::Valid: {
             auto instance = m_parent->instance();
             printJavaInfo(result.javaVersion.toString(), result.mojangPlatform, result.realPlatform, result.javaVendor);
             instance->settings()->set("JavaVersion", result.javaVersion.toString());

launcher/launch/steps/CheckJava.h

@@ -28,7 +28,7 @@ class CheckJava : public LaunchStep {
     virtual void executeTask();
     virtual bool canAbort() const { return false; }
    private slots:
-    void checkJavaFinished(JavaCheckResult result);
+    void checkJavaFinished(const JavaChecker::Result& result);
 
    private:
     void printJavaInfo(const QString& version, const QString& architecture, const QString& realArchitecture, const QString& vendor);
@@ -37,5 +37,5 @@ class CheckJava : public LaunchStep {
    private:
     QString m_javaPath;
     QString m_javaSignature;
-    JavaCheckerPtr m_JavaChecker;
+    JavaChecker::Ptr m_JavaChecker;
 };

launcher/meta/VersionList.cpp

@@ -100,6 +100,13 @@ QVariant VersionList::data(const QModelIndex& index, int role) const
             return QVariant::fromValue(version);
         case RecommendedRole:
             return version->isRecommended();
+        case JavaMajorRole: {
+            auto major = version->version();
+            if (major.startsWith("java")) {
+                major = "Java " + major.mid(4);
+            }
+            return major;
+        }
         // FIXME: this should be determined in whatever view/proxy is used...
         // case LatestRole: return version == getLatestStable();
         default:
@@ -109,10 +116,14 @@ QVariant VersionList::data(const QModelIndex& index, int role) const
 
 BaseVersionList::RoleList VersionList::providesRoles() const
 {
-    return { VersionPointerRole, VersionRole,  VersionIdRole, ParentVersionRole, TypeRole,   UidRole,
+    return m_provided_roles;
-             TimeRole,           RequiresRole, SortRole,      RecommendedRole,   LatestRole, VersionPtrRole };
 }
 
+void VersionList::setProvidedRoles(RoleList roles)
+{
+    m_provided_roles = roles;
+};
+
 QHash<int, QByteArray> VersionList::roleNames() const
 {
     QHash<int, QByteArray> roles = BaseVersionList::roleNames();

launcher/meta/VersionList.h

@@ -48,6 +48,8 @@ class VersionList : public BaseVersionList, public BaseEntity {
     RoleList providesRoles() const override;
     QHash<int, QByteArray> roleNames() const override;
 
+    void setProvidedRoles(RoleList roles);
+
     QString localFilename() const override;
 
     QString uid() const { return m_uid; }
@@ -83,6 +85,9 @@ class VersionList : public BaseVersionList, public BaseEntity {
 
     Version::Ptr m_recommended;
 
+    RoleList m_provided_roles = { VersionPointerRole, VersionRole,  VersionIdRole, ParentVersionRole, TypeRole,   UidRole,
+                                  TimeRole,           RequiresRole, SortRole,      RecommendedRole,   LatestRole, VersionPtrRole };
+
     void setupAddedVersion(int row, const Version::Ptr& version);
 };
 }  // namespace Meta

launcher/minecraft/LaunchProfile.cpp

@@ -164,6 +164,11 @@ void LaunchProfile::applyCompatibleJavaMajors(QList<int>& javaMajor)
 {
     m_compatibleJavaMajors.append(javaMajor);
 }
+void LaunchProfile::applyCompatibleJavaName(QString javaName)
+{
+    if (!javaName.isEmpty())
+        m_compatibleJavaName = javaName;
+}
 
 void LaunchProfile::applyLibrary(LibraryPtr library, const RuntimeContext& runtimeContext)
 {
@@ -334,6 +339,11 @@ const QList<int>& LaunchProfile::getCompatibleJavaMajors() const
     return m_compatibleJavaMajors;
 }
 
+const QString LaunchProfile::getCompatibleJavaName() const
+{
+    return m_compatibleJavaName;
+}
+
 void LaunchProfile::getLibraryFiles(const RuntimeContext& runtimeContext,
                                     QStringList& jars,
                                     QStringList& nativeJars,

launcher/minecraft/LaunchProfile.h

@@ -59,6 +59,7 @@ class LaunchProfile : public ProblemProvider {
     void applyMavenFile(LibraryPtr library, const RuntimeContext& runtimeContext);
     void applyAgent(AgentPtr agent, const RuntimeContext& runtimeContext);
     void applyCompatibleJavaMajors(QList<int>& javaMajor);
+    void applyCompatibleJavaName(QString javaName);
     void applyMainJar(LibraryPtr jar);
     void applyProblemSeverity(ProblemSeverity severity);
     /// clear the profile
@@ -80,6 +81,7 @@ class LaunchProfile : public ProblemProvider {
     const QList<LibraryPtr>& getMavenFiles() const;
     const QList<AgentPtr>& getAgents() const;
     const QList<int>& getCompatibleJavaMajors() const;
+    const QString getCompatibleJavaName() const;
     const LibraryPtr getMainJar() const;
     void getLibraryFiles(const RuntimeContext& runtimeContext,
                          QStringList& jars,
@@ -150,5 +152,7 @@ class LaunchProfile : public ProblemProvider {
     /// compatible java major versions
     QList<int> m_compatibleJavaMajors;
 
+    QString m_compatibleJavaName;
+
     ProblemSeverity m_problemSeverity = ProblemSeverity::None;
 };

launcher/minecraft/MinecraftInstance.cpp

@@ -38,6 +38,8 @@
 #include "MinecraftInstance.h"
 #include "Application.h"
 #include "BuildConfig.h"
+#include "QObjectPtr.h"
+#include "minecraft/launch/AutoInstallJava.h"
 #include "minecraft/launch/CreateGameFolders.h"
 #include "minecraft/launch/ExtractNatives.h"
 #include "minecraft/launch/PrintInstanceInfo.h"
@@ -134,25 +136,21 @@ void MinecraftInstance::loadSpecificSettings()
         return;
 
     // Java Settings
-    auto javaOverride = m_settings->registerSetting("OverrideJava", false);
     auto locationOverride = m_settings->registerSetting("OverrideJavaLocation", false);
     auto argsOverride = m_settings->registerSetting("OverrideJavaArgs", false);
-
+    m_settings->registerSetting("AutomaticJava", false);
-    // combinations
-    auto javaOrLocation = std::make_shared<OrSetting>("JavaOrLocationOverride", javaOverride, locationOverride);
-    auto javaOrArgs = std::make_shared<OrSetting>("JavaOrArgsOverride", javaOverride, argsOverride);
 
     if (auto global_settings = globalSettings()) {
-        m_settings->registerOverride(global_settings->getSetting("JavaPath"), javaOrLocation);
+        m_settings->registerOverride(global_settings->getSetting("JavaPath"), locationOverride);
-        m_settings->registerOverride(global_settings->getSetting("JvmArgs"), javaOrArgs);
+        m_settings->registerOverride(global_settings->getSetting("JvmArgs"), argsOverride);
-        m_settings->registerOverride(global_settings->getSetting("IgnoreJavaCompatibility"), javaOrLocation);
+        m_settings->registerOverride(global_settings->getSetting("IgnoreJavaCompatibility"), locationOverride);
 
         // special!
-        m_settings->registerPassthrough(global_settings->getSetting("JavaSignature"), javaOrLocation);
+        m_settings->registerPassthrough(global_settings->getSetting("JavaSignature"), locationOverride);
-        m_settings->registerPassthrough(global_settings->getSetting("JavaArchitecture"), javaOrLocation);
+        m_settings->registerPassthrough(global_settings->getSetting("JavaArchitecture"), locationOverride);
-        m_settings->registerPassthrough(global_settings->getSetting("JavaRealArchitecture"), javaOrLocation);
+        m_settings->registerPassthrough(global_settings->getSetting("JavaRealArchitecture"), locationOverride);
-        m_settings->registerPassthrough(global_settings->getSetting("JavaVersion"), javaOrLocation);
+        m_settings->registerPassthrough(global_settings->getSetting("JavaVersion"), locationOverride);
-        m_settings->registerPassthrough(global_settings->getSetting("JavaVendor"), javaOrLocation);
+        m_settings->registerPassthrough(global_settings->getSetting("JavaVendor"), locationOverride);
 
         // Window Size
         auto windowSetting = m_settings->registerSetting("OverrideWindow", false);
@@ -1060,11 +1058,6 @@ shared_qobject_ptr<LaunchTask> MinecraftInstance::createLaunchTask(AuthSessionPt
         process->appendStep(makeShared<TextPrint>(pptr, "Minecraft folder is:\n" + gameRoot() + "\n\n", MessageLevel::Launcher));
     }
 
-    // check java
-    {
-        process->appendStep(makeShared<CheckJava>(pptr));
-    }
-
     // create the .minecraft folder and server-resource-packs (workaround for Minecraft bug MCL-3732)
     {
         process->appendStep(makeShared<CreateGameFolders>(pptr));
@@ -1107,6 +1100,12 @@ shared_qobject_ptr<LaunchTask> MinecraftInstance::createLaunchTask(AuthSessionPt
         process->appendStep(makeShared<Update>(pptr, Net::Mode::Offline));
     }
 
+    // check java
+    {
+        process->appendStep(makeShared<AutoInstallJava>(pptr));
+        process->appendStep(makeShared<CheckJava>(pptr));
+    }
+
     // if there are any jar mods
     {
         process->appendStep(makeShared<ModMinecraftJar>(pptr));

launcher/minecraft/MojangVersionFormat.cpp

@@ -185,6 +185,9 @@ void MojangVersionFormat::readVersionProperties(const QJsonObject& in, VersionFi
             out->compatibleJavaMajors.append(requireInteger(compatible));
         }
     }
+    if (in.contains("compatibleJavaName")) {
+        out->compatibleJavaName = requireString(in.value("compatibleJavaName"));
+    }
 
     if (in.contains("downloads")) {
         auto downloadsObj = requireObject(in, "downloads");
@@ -259,6 +262,9 @@ void MojangVersionFormat::writeVersionProperties(const VersionFile* in, QJsonObj
         }
         out.insert("compatibleJavaMajors", compatibleJavaMajorsOut);
     }
+    if (!in->compatibleJavaName.isEmpty()) {
+        writeString(out, "compatibleJavaName", in->compatibleJavaName);
+    }
 }
 
 QJsonDocument MojangVersionFormat::versionFileToJson(const VersionFilePtr& patch)

launcher/minecraft/OneSixVersionFormat.cpp

@@ -36,6 +36,8 @@
 #include "OneSixVersionFormat.h"
 #include <Json.h>
 #include <minecraft/MojangVersionFormat.h>
+#include <QList>
+#include "java/JavaMetadata.h"
 #include "minecraft/Agent.h"
 #include "minecraft/ParseUtils.h"
 
@@ -255,6 +257,13 @@ VersionFilePtr OneSixVersionFormat::versionFileFromJson(const QJsonDocument& doc
         out->m_volatile = requireBoolean(root, "volatile");
     }
 
+    if (root.contains("runtimes")) {
+        out->runtimes = {};
+        for (auto runtime : ensureArray(root, "runtimes")) {
+            out->runtimes.append(Java::parseJavaMeta(ensureObject(runtime)));
+        }
+    }
+
     /* removed features that shouldn't be used */
     if (root.contains("tweakers")) {
         out->addProblem(ProblemSeverity::Error, QObject::tr("Version file contains unsupported element 'tweakers'"));

launcher/minecraft/VersionFile.cpp

@@ -73,6 +73,7 @@ void VersionFile::applyTo(LaunchProfile* profile, const RuntimeContext& runtimeC
     profile->applyMods(mods);
     profile->applyTraits(traits);
     profile->applyCompatibleJavaMajors(compatibleJavaMajors);
+    profile->applyCompatibleJavaName(compatibleJavaName);
 
     for (auto library : libraries) {
         profile->applyLibrary(library, runtimeContext);

launcher/minecraft/VersionFile.h

@@ -36,6 +36,8 @@
 #pragma once
 
 #include <QDateTime>
+#include <QHash>
+#include <QList>
 #include <QSet>
 #include <QString>
 #include <QStringList>
@@ -45,6 +47,7 @@
 #include "Agent.h"
 #include "Library.h"
 #include "ProblemProvider.h"
+#include "java/JavaMetadata.h"
 #include "minecraft/Rule.h"
 
 class PackProfile;
@@ -98,6 +101,9 @@ class VersionFile : public ProblemContainer {
     /// Mojang: list of compatible java majors
     QList<int> compatibleJavaMajors;
 
+    /// Mojang: the name of recommended java version
+    QString compatibleJavaName;
+
     /// Mojang: type of the Minecraft version
     QString type;
 
@@ -149,6 +155,8 @@ class VersionFile : public ProblemContainer {
     /// is volatile -- may be removed as soon as it is no longer needed by something else
     bool m_volatile = false;
 
+    QList<Java::MetadataPtr> runtimes;
+
    public:
     // Mojang: DEPRECATED list of 'downloads' - client jar, server jar, windows server exe, maybe more.
     QMap<QString, std::shared_ptr<MojangDownloadInfo>> mojangDownloads;

launcher/minecraft/launch/AutoInstallJava.cpp

@@ -0,0 +1,242 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ *      Copyright 2013-2021 MultiMC Contributors
+ *
+ *      Licensed under the Apache License, Version 2.0 (the "License");
+ *      you may not use this file except in compliance with the License.
+ *      You may obtain a copy of the License at
+ *
+ *          http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *      Unless required by applicable law or agreed to in writing, software
+ *      distributed under the License is distributed on an "AS IS" BASIS,
+ *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *      See the License for the specific language governing permissions and
+ *      limitations under the License.
+ */
+
+#include "AutoInstallJava.h"
+#include <QDir>
+#include <QFileInfo>
+#include <memory>
+
+#include "Application.h"
+#include "FileSystem.h"
+#include "MessageLevel.h"
+#include "SysInfo.h"
+#include "java/JavaInstall.h"
+#include "java/JavaInstallList.h"
+#include "java/JavaUtils.h"
+#include "java/JavaVersion.h"
+#include "java/download/ArchiveDownloadTask.h"
+#include "java/download/ManifestDownloadTask.h"
+#include "meta/Index.h"
+#include "minecraft/MinecraftInstance.h"
+#include "minecraft/PackProfile.h"
+#include "net/Mode.h"
+
+AutoInstallJava::AutoInstallJava(LaunchTask* parent)
+    : LaunchStep(parent)
+    , m_instance(std::dynamic_pointer_cast<MinecraftInstance>(m_parent->instance()))
+    , m_supported_arch(SysInfo::getSupportedJavaArchitecture()) {};
+
+void AutoInstallJava::executeTask()
+{
+    auto settings = m_instance->settings();
+    if (!APPLICATION->settings()->get("AutomaticJavaSwitch").toBool() ||
+        (settings->get("OverrideJavaLocation").toBool() && QFileInfo::exists(settings->get("JavaPath").toString()))) {
+        emitSucceeded();
+        return;
+    }
+    auto packProfile = m_instance->getPackProfile();
+    if (!APPLICATION->settings()->get("AutomaticJavaDownload").toBool()) {
+        auto javas = APPLICATION->javalist();
+        m_current_task = javas->getLoadTask();
+        connect(m_current_task.get(), &Task::finished, this, [this, javas, packProfile] {
+            for (auto i = 0; i < javas->count(); i++) {
+                auto java = std::dynamic_pointer_cast<JavaInstall>(javas->at(i));
+                if (java && packProfile->getProfile()->getCompatibleJavaMajors().contains(java->id.major())) {
+                    if (!java->is_64bit) {
+                        emit logLine(tr("The automatic Java mechanism detected a 32-bit installation of Java."), MessageLevel::Info);
+                    }
+                    setJavaPath(java->path);
+                    return;
+                }
+            }
+            emit logLine(tr("No compatible Java version was found. Using the default one."), MessageLevel::Warning);
+            emitSucceeded();
+        });
+        connect(m_current_task.get(), &Task::progress, this, &AutoInstallJava::setProgress);
+        connect(m_current_task.get(), &Task::stepProgress, this, &AutoInstallJava::propagateStepProgress);
+        connect(m_current_task.get(), &Task::status, this, &AutoInstallJava::setStatus);
+        connect(m_current_task.get(), &Task::details, this, &AutoInstallJava::setDetails);
+        emit progressReportingRequest();
+        return;
+    }
+    if (m_supported_arch.isEmpty()) {
+        emit logLine(tr("Your system (%1-%2) is not compatible with automatic Java installation. Using the default Java path.")
+                         .arg(SysInfo::currentSystem(), SysInfo::useQTForArch()),
+                     MessageLevel::Warning);
+        emitSucceeded();
+        return;
+    }
+    auto wantedJavaName = packProfile->getProfile()->getCompatibleJavaName();
+    if (wantedJavaName.isEmpty()) {
+        emit logLine(tr("Your meta information is out of date or doesn't have the information necessary to determine what installation of "
+                        "Java should be used. "
+                        "Using the default Java path."),
+                     MessageLevel::Warning);
+        emitSucceeded();
+        return;
+    }
+    QDir javaDir(APPLICATION->javaPath());
+    auto wantedJavaPath = javaDir.absoluteFilePath(wantedJavaName);
+    if (QFileInfo::exists(wantedJavaPath)) {
+        setJavaPathFromPartial();
+        return;
+    }
+    auto versionList = APPLICATION->metadataIndex()->get("net.minecraft.java");
+    m_current_task = versionList->getLoadTask();
+    connect(m_current_task.get(), &Task::succeeded, this, &AutoInstallJava::tryNextMajorJava);
+    connect(m_current_task.get(), &Task::failed, this, &AutoInstallJava::emitFailed);
+    connect(m_current_task.get(), &Task::progress, this, &AutoInstallJava::setProgress);
+    connect(m_current_task.get(), &Task::stepProgress, this, &AutoInstallJava::propagateStepProgress);
+    connect(m_current_task.get(), &Task::status, this, &AutoInstallJava::setStatus);
+    connect(m_current_task.get(), &Task::details, this, &AutoInstallJava::setDetails);
+    if (!m_current_task->isRunning()) {
+        m_current_task->start();
+    }
+    emit progressReportingRequest();
+}
+
+void AutoInstallJava::setJavaPath(QString path)
+{
+    auto settings = m_instance->settings();
+    settings->set("OverrideJavaLocation", true);
+    settings->set("JavaPath", path);
+    settings->set("AutomaticJava", true);
+    emit logLine(tr("Compatible Java found at: %1.").arg(path), MessageLevel::Info);
+    emitSucceeded();
+}
+
+void AutoInstallJava::setJavaPathFromPartial()
+{
+    auto packProfile = m_instance->getPackProfile();
+    auto javaName = packProfile->getProfile()->getCompatibleJavaName();
+    QDir javaDir(APPLICATION->javaPath());
+    // just checking if the executable is there should suffice
+    // but if needed this can be achieved through refreshing the javalist
+    // and retrieving the path that contains the java name
+    auto relativeBinary = FS::PathCombine(javaName, "bin", JavaUtils::javaExecutable);
+    auto finalPath = javaDir.absoluteFilePath(relativeBinary);
+    if (QFileInfo::exists(finalPath)) {
+        setJavaPath(finalPath);
+    } else {
+        emit logLine(tr("No compatible Java version was found (the binary file does not exist). Using the default one."),
+                     MessageLevel::Warning);
+        emitSucceeded();
+    }
+    return;
+}
+
+void AutoInstallJava::downloadJava(Meta::Version::Ptr version, QString javaName)
+{
+    auto runtimes = version->data()->runtimes;
+    for (auto java : runtimes) {
+        if (java->runtimeOS == m_supported_arch && java->name() == javaName) {
+            QDir javaDir(APPLICATION->javaPath());
+            auto final_path = javaDir.absoluteFilePath(java->m_name);
+            switch (java->downloadType) {
+                case Java::DownloadType::Manifest:
+                    m_current_task = makeShared<Java::ManifestDownloadTask>(java->url, final_path, java->checksumType, java->checksumHash);
+                    break;
+                case Java::DownloadType::Archive:
+                    m_current_task = makeShared<Java::ArchiveDownloadTask>(java->url, final_path, java->checksumType, java->checksumHash);
+                    break;
+                case Java::DownloadType::Unknown:
+                    emitFailed(tr("Could not determine Java download type!"));
+                    return;
+            }
+            auto deletePath = [final_path] { FS::deletePath(final_path); };
+            connect(m_current_task.get(), &Task::failed, this, [this, deletePath](QString reason) {
+                deletePath();
+                emitFailed(reason);
+            });
+            connect(this, &Task::aborted, this, [this, deletePath] {
+                m_current_task->abort();
+                deletePath();
+            });
+            connect(m_current_task.get(), &Task::succeeded, this, &AutoInstallJava::setJavaPathFromPartial);
+            connect(m_current_task.get(), &Task::failed, this, &AutoInstallJava::tryNextMajorJava);
+            connect(m_current_task.get(), &Task::progress, this, &AutoInstallJava::setProgress);
+            connect(m_current_task.get(), &Task::stepProgress, this, &AutoInstallJava::propagateStepProgress);
+            connect(m_current_task.get(), &Task::status, this, &AutoInstallJava::setStatus);
+            connect(m_current_task.get(), &Task::details, this, &AutoInstallJava::setDetails);
+            m_current_task->start();
+            return;
+        }
+    }
+    tryNextMajorJava();
+}
+
+void AutoInstallJava::tryNextMajorJava()
+{
+    if (!isRunning())
+        return;
+    auto versionList = APPLICATION->metadataIndex()->get("net.minecraft.java");
+    auto packProfile = m_instance->getPackProfile();
+    auto wantedJavaName = packProfile->getProfile()->getCompatibleJavaName();
+    auto majorJavaVersions = packProfile->getProfile()->getCompatibleJavaMajors();
+    if (m_majorJavaVersionIndex >= majorJavaVersions.length()) {
+        emit logLine(
+            tr("No versions of Java were found for your operating system: %1-%2").arg(SysInfo::currentSystem(), SysInfo::useQTForArch()),
+            MessageLevel::Warning);
+        emit logLine(tr("No compatible version of Java was found. Using the default one."), MessageLevel::Warning);
+        emitSucceeded();
+        return;
+    }
+    auto majorJavaVersion = majorJavaVersions[m_majorJavaVersionIndex];
+    m_majorJavaVersionIndex++;
+
+    auto javaMajor = versionList->getVersion(QString("java%1").arg(majorJavaVersion));
+
+    if (javaMajor->isLoaded()) {
+        downloadJava(javaMajor, wantedJavaName);
+    } else {
+        m_current_task = APPLICATION->metadataIndex()->loadVersion("net.minecraft.java", javaMajor->version(), Net::Mode::Online);
+        connect(m_current_task.get(), &Task::succeeded, this,
+                [this, javaMajor, wantedJavaName] { downloadJava(javaMajor, wantedJavaName); });
+        connect(m_current_task.get(), &Task::failed, this, &AutoInstallJava::tryNextMajorJava);
+        connect(m_current_task.get(), &Task::progress, this, &AutoInstallJava::setProgress);
+        connect(m_current_task.get(), &Task::stepProgress, this, &AutoInstallJava::propagateStepProgress);
+        connect(m_current_task.get(), &Task::status, this, &AutoInstallJava::setStatus);
+        connect(m_current_task.get(), &Task::details, this, &AutoInstallJava::setDetails);
+        if (!m_current_task->isRunning()) {
+            m_current_task->start();
+        }
+    }
+}
+bool AutoInstallJava::abort()
+{
+    if (m_current_task && m_current_task->canAbort())
+        return m_current_task->abort();
+    return true;
+}

launcher/minecraft/launch/AutoInstallJava.h

@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2023-2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ *      Copyright 2013-2021 MultiMC Contributors
+ *
+ *      Licensed under the Apache License, Version 2.0 (the "License");
+ *      you may not use this file except in compliance with the License.
+ *      You may obtain a copy of the License at
+ *
+ *          http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *      Unless required by applicable law or agreed to in writing, software
+ *      distributed under the License is distributed on an "AS IS" BASIS,
+ *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *      See the License for the specific language governing permissions and
+ *      limitations under the License.
+ */
+
+#pragma once
+
+#include <launch/LaunchStep.h>
+#include <launch/LaunchTask.h>
+#include "java/JavaMetadata.h"
+#include "meta/Version.h"
+#include "minecraft/MinecraftInstance.h"
+#include "tasks/Task.h"
+
+class AutoInstallJava : public LaunchStep {
+    Q_OBJECT
+
+   public:
+    explicit AutoInstallJava(LaunchTask* parent);
+    ~AutoInstallJava() override = default;
+
+    void executeTask() override;
+    bool canAbort() const override { return m_current_task ? m_current_task->canAbort() : false; }
+    bool abort() override;
+
+   protected:
+    void setJavaPath(QString path);
+    void setJavaPathFromPartial();
+    void downloadJava(Meta::Version::Ptr version, QString javaName);
+    void tryNextMajorJava();
+
+   private:
+    MinecraftInstancePtr m_instance;
+    Task::Ptr m_current_task;
+
+    qsizetype m_majorJavaVersionIndex = 0;
+    const QString m_supported_arch;
+};

launcher/minecraft/launch/VerifyJavaInstall.cpp

@@ -34,7 +34,12 @@
  */
 
 #include "VerifyJavaInstall.h"
+#include <memory>
 
+#include "Application.h"
+#include "MessageLevel.h"
+#include "java/JavaInstall.h"
+#include "java/JavaInstallList.h"
 #include "java/JavaVersion.h"
 #include "minecraft/MinecraftInstance.h"
 #include "minecraft/PackProfile.h"
@@ -46,6 +51,15 @@ void VerifyJavaInstall::executeTask()
     auto settings = instance->settings();
     auto storedVersion = settings->get("JavaVersion").toString();
     auto ignoreCompatibility = settings->get("IgnoreJavaCompatibility").toBool();
+    auto javaArchitecture = settings->get("JavaArchitecture").toString();
+    auto maxMemAlloc = settings->get("MaxMemAlloc").toInt();
+
+    if (javaArchitecture == "32" && maxMemAlloc > 2048) {
+        emit logLine(tr("Max memory allocation exceeds the supported value.\n"
+                        "The selected installation of Java is 32-bit and doesn't support more than 2048MiB of RAM.\n"
+                        "The instance may not start due to this."),
+                     MessageLevel::Error);
+    }
 
     auto compatibleMajors = packProfile->getProfile()->getCompatibleJavaMajors();
 

launcher/resources/multimc/multimc.qrc

@@ -353,5 +353,11 @@
         <file>scalable/instances/neoforged.svg</file>
         <file>128x128/instances/forge.png</file>  <!-- LGPL3 Forge Development LLC -->
         <file>128x128/instances/liteloader.png</file>  <!-- CC-BY-SA 4.0 LiteLoader -->
+
+        <!-- java providers -->
+        <file>scalable/adoptium.svg</file>  <!-- The Adoptium Logo is a registered trademark of the Eclipse Foundation. -->
+        <file>scalable/azul.svg</file>  <!-- Azul, Zulu, Azul Systems, the Azul Systems logo, Azul Zulu are either registered trademarks or trademarks of Azul Systems, registered in the U.S. and elsewhere. -->
+        <file>scalable/mojang.svg</file>  <!-- The Mojang Logo is a registered trademark of Mojang AB. -->
+
     </qresource>
 </RCC>

launcher/resources/multimc/scalable/adoptium.svg

@@ -0,0 +1,180 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   sodipodi:docname="Eclipse_Adoptium_Logo_A_only_no_outline.svg"
+   inkscape:version="1.3 (0e150ed6c4, 2023-07-21)"
+   id="svg8"
+   version="1.1"
+   viewBox="0 0 800 800"
+   height="800"
+   width="800"
+   inkscape:export-filename="Eclipse_Adoptium_Logo.png"
+   inkscape:export-xdpi="61.439999"
+   inkscape:export-ydpi="61.439999"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <defs
+     id="defs2">
+    <clipPath
+       clipPathUnits="userSpaceOnUse"
+       id="clipPath242">
+      <path
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+         id="path240" />
+    </clipPath>
+    <linearGradient
+       x1="0"
+       y1="0"
+       x2="1"
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+       gradientUnits="userSpaceOnUse"
+       gradientTransform="matrix(-481.882,253.823,253.823,481.882,1152.35,658.95)"
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+       id="linearGradient248">
+      <stop
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launcher/resources/multimc/scalable/azul.svg

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" width="64" height="64" viewBox="0 0 64 64" fill="none" style="scroll-behavior: auto !important;">
+  <path d="M26.792 4.49429L7.62244 44.4309C7.20797 45.2944 8.12743 46.1903 8.97988 45.7536L28.26 35.8772C28.6557 35.6745 29.1376 35.7574 29.4429 36.0805L53.2128 61.2399C53.994 62.0668 55.3295 61.1553 54.844 60.1264L28.5979 4.50031C28.2386 3.73874 27.1564 3.73514 26.792 4.49429Z" fill="#00374A"/>
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+  <path d="M34.0172 15.5765L60.9237 19.1042C61.9046 19.2329 62.1231 20.5555 61.2357 20.9928L33.4872 34.6659L9.3254 45.9918C8.34481 46.4514 7.43514 45.2419 8.14881 44.4273L33.135 15.909C33.3551 15.6578 33.686 15.5331 34.0172 15.5765Z" fill="url(#paint1_linear_3578_2134)" fill-opacity="0.7" style="mix-blend-mode:overlay"/>
+  <defs>
+    <linearGradient id="paint0_linear_3578_2134" x1="31.2618" y1="2.59998" x2="31.2618" y2="65.8" gradientUnits="userSpaceOnUse">
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+    </linearGradient>
+    <linearGradient id="paint1_linear_3578_2134" x1="46.2268" y1="4.17812" x2="31.5574" y2="56.1518" gradientUnits="userSpaceOnUse">
+      <stop stop-color="white" stop-opacity="0"/>
+      <stop offset="1" stop-color="white"/>
+    </linearGradient>
+  </defs>
+</svg>

launcher/resources/multimc/scalable/mojang.svg

@@ -0,0 +1,55 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   version="1.1"
+   width="800"
+   height="800"
+   viewBox="0 0 800 800"
+   xml:space="preserve"
+   style="scroll-behavior: auto !important;"
+   id="svg4"
+   sodipodi:docname="Mojang_Studios_Logo_(2020,_icon).svg"
+   inkscape:export-filename="Mojang_Studios_Logo_(2020,_icon).png"
+   inkscape:export-xdpi="61.439999"
+   inkscape:export-ydpi="61.439999"
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+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg"><sodipodi:namedview
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+   pagecolor="#505050"
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+   inkscape:window-height="1369"
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+   inkscape:window-maximized="1"
+   inkscape:current-layer="g3" />&#10;<desc
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+   points="50,50 50,-50 -50,-50 -50,50 "
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launcher/ui/dialogs/VersionSelectDialog.h

@@ -26,10 +26,6 @@ class QDialogButtonBox;
 class VersionSelectWidget;
 class QPushButton;
 
-namespace Ui {
-class VersionSelectDialog;
-}
-
 class VersionProxyModel;
 
 class VersionSelectDialog : public QDialog {

launcher/ui/java/InstallJavaDialog.cpp

@@ -0,0 +1,338 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "InstallJavaDialog.h"
+
+#include <QCheckBox>
+#include <QDialogButtonBox>
+#include <QMessageBox>
+#include <QPushButton>
+#include <QVBoxLayout>
+#include <QWidget>
+
+#include "Application.h"
+#include "BaseVersionList.h"
+#include "FileSystem.h"
+#include "Filter.h"
+#include "java/download/ArchiveDownloadTask.h"
+#include "java/download/ManifestDownloadTask.h"
+#include "meta/Index.h"
+#include "meta/VersionList.h"
+#include "minecraft/MinecraftInstance.h"
+#include "minecraft/PackProfile.h"
+#include "ui/dialogs/CustomMessageBox.h"
+#include "ui/dialogs/ProgressDialog.h"
+#include "ui/java/VersionList.h"
+#include "ui/widgets/PageContainer.h"
+#include "ui/widgets/VersionSelectWidget.h"
+
+class InstallJavaPage : public QWidget, public BasePage {
+   public:
+    Q_OBJECT
+   public:
+    explicit InstallJavaPage(const QString& id, const QString& iconName, const QString& name, QWidget* parent = nullptr)
+        : QWidget(parent), uid(id), iconName(iconName), name(name)
+    {
+        setObjectName(QStringLiteral("VersionSelectWidget"));
+        horizontalLayout = new QHBoxLayout(this);
+        horizontalLayout->setObjectName(QStringLiteral("horizontalLayout"));
+        horizontalLayout->setContentsMargins(0, 0, 0, 0);
+
+        majorVersionSelect = new VersionSelectWidget(this);
+        majorVersionSelect->selectCurrent();
+        majorVersionSelect->setEmptyString(tr("No java versions are currently available in the meta."));
+        majorVersionSelect->setEmptyErrorString(tr("Couldn't load or download the java version lists!"));
+        horizontalLayout->addWidget(majorVersionSelect, 1);
+
+        javaVersionSelect = new VersionSelectWidget(this);
+        javaVersionSelect->setEmptyString(tr("No java versions are currently available for your OS."));
+        javaVersionSelect->setEmptyErrorString(tr("Couldn't load or download the java version lists!"));
+        horizontalLayout->addWidget(javaVersionSelect, 4);
+        connect(majorVersionSelect, &VersionSelectWidget::selectedVersionChanged, this, &InstallJavaPage::setSelectedVersion);
+        connect(majorVersionSelect, &VersionSelectWidget::selectedVersionChanged, this, &InstallJavaPage::selectionChanged);
+        connect(javaVersionSelect, &VersionSelectWidget::selectedVersionChanged, this, &InstallJavaPage::selectionChanged);
+
+        QMetaObject::connectSlotsByName(this);
+    }
+    ~InstallJavaPage()
+    {
+        delete horizontalLayout;
+        delete majorVersionSelect;
+        delete javaVersionSelect;
+    }
+
+    //! loads the list if needed.
+    void initialize(Meta::VersionList::Ptr vlist)
+    {
+        vlist->setProvidedRoles({ BaseVersionList::JavaMajorRole, BaseVersionList::RecommendedRole, BaseVersionList::VersionPointerRole });
+        majorVersionSelect->initialize(vlist.get());
+    }
+
+    void setSelectedVersion(BaseVersion::Ptr version)
+    {
+        auto dcast = std::dynamic_pointer_cast<Meta::Version>(version);
+        if (!dcast) {
+            return;
+        }
+        javaVersionSelect->initialize(new Java::VersionList(dcast, this));
+        javaVersionSelect->selectCurrent();
+    }
+
+    QString id() const override { return uid; }
+    QString displayName() const override { return name; }
+    QIcon icon() const override { return APPLICATION->getThemedIcon(iconName); }
+
+    void openedImpl() override
+    {
+        if (loaded)
+            return;
+
+        const auto versions = APPLICATION->metadataIndex()->get(uid);
+        if (!versions)
+            return;
+
+        initialize(versions);
+        loaded = true;
+    }
+
+    void setParentContainer(BasePageContainer* container) override
+    {
+        auto dialog = dynamic_cast<QDialog*>(dynamic_cast<PageContainer*>(container)->parent());
+        connect(javaVersionSelect->view(), &QAbstractItemView::doubleClicked, dialog, &QDialog::accept);
+    }
+
+    BaseVersion::Ptr selectedVersion() const { return javaVersionSelect->selectedVersion(); }
+    void selectSearch() { javaVersionSelect->selectSearch(); }
+    void loadList()
+    {
+        majorVersionSelect->loadList();
+        javaVersionSelect->loadList();
+    }
+
+   public slots:
+    void setRecommendedMajors(const QStringList& majors)
+    {
+        m_recommended_majors = majors;
+        recommendedFilterChanged();
+    }
+    void setRecomend(bool recomend)
+    {
+        m_recommend = recomend;
+        recommendedFilterChanged();
+    }
+    void recommendedFilterChanged()
+    {
+        if (m_recommend) {
+            majorVersionSelect->setFilter(BaseVersionList::ModelRoles::JavaMajorRole, new ExactListFilter(m_recommended_majors));
+        } else {
+            majorVersionSelect->setFilter(BaseVersionList::ModelRoles::JavaMajorRole, new ExactListFilter());
+        }
+    }
+
+   signals:
+    void selectionChanged();
+
+   private:
+    const QString uid;
+    const QString iconName;
+    const QString name;
+    bool loaded = false;
+
+    QHBoxLayout* horizontalLayout = nullptr;
+    VersionSelectWidget* majorVersionSelect = nullptr;
+    VersionSelectWidget* javaVersionSelect = nullptr;
+
+    QStringList m_recommended_majors;
+    bool m_recommend;
+};
+
+static InstallJavaPage* pageCast(BasePage* page)
+{
+    auto result = dynamic_cast<InstallJavaPage*>(page);
+    Q_ASSERT(result != nullptr);
+    return result;
+}
+namespace Java {
+QStringList getRecommendedJavaVersionsFromVersionList(Meta::VersionList::Ptr list)
+{
+    QStringList recommendedJavas;
+    for (auto ver : list->versions()) {
+        auto major = ver->version();
+        if (major.startsWith("java")) {
+            major = "Java " + major.mid(4);
+        }
+        recommendedJavas.append(major);
+    }
+    return recommendedJavas;
+}
+
+InstallDialog::InstallDialog(const QString& uid, BaseInstance* instance, QWidget* parent)
+    : QDialog(parent), container(new PageContainer(this, QString(), this)), buttons(new QDialogButtonBox(this))
+{
+    auto layout = new QVBoxLayout(this);
+
+    container->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Expanding);
+    layout->addWidget(container);
+
+    auto buttonLayout = new QHBoxLayout(this);
+    auto refreshLayout = new QHBoxLayout(this);
+
+    auto refreshButton = new QPushButton(tr("&Refresh"), this);
+    connect(refreshButton, &QPushButton::clicked, this, [this] { pageCast(container->selectedPage())->loadList(); });
+    refreshLayout->addWidget(refreshButton);
+
+    auto recommendedCheckBox = new QCheckBox("Recommended", this);
+    recommendedCheckBox->setCheckState(Qt::CheckState::Checked);
+    connect(recommendedCheckBox, &QCheckBox::stateChanged, this, [this](int state) {
+        for (BasePage* page : container->getPages()) {
+            pageCast(page)->setRecomend(state == Qt::Checked);
+        }
+    });
+
+    refreshLayout->addWidget(recommendedCheckBox);
+    buttonLayout->addLayout(refreshLayout);
+
+    buttons->setOrientation(Qt::Horizontal);
+    buttons->setStandardButtons(QDialogButtonBox::Cancel | QDialogButtonBox::Ok);
+    buttons->button(QDialogButtonBox::Ok)->setText(tr("Download"));
+    connect(buttons, &QDialogButtonBox::accepted, this, &QDialog::accept);
+    connect(buttons, &QDialogButtonBox::rejected, this, &QDialog::reject);
+    buttonLayout->addWidget(buttons);
+
+    layout->addLayout(buttonLayout);
+
+    setWindowTitle(dialogTitle());
+    setWindowModality(Qt::WindowModal);
+    resize(840, 480);
+
+    QStringList recommendedJavas;
+    if (auto mcInst = dynamic_cast<MinecraftInstance*>(instance); mcInst) {
+        auto mc = mcInst->getPackProfile()->getComponent("net.minecraft");
+        if (mc) {
+            auto file = mc->getVersionFile();  // no need for load as it should already be loaded
+            if (file) {
+                for (auto major : file->compatibleJavaMajors) {
+                    recommendedJavas.append(QString("Java %1").arg(major));
+                }
+            }
+        }
+    } else {
+        const auto versions = APPLICATION->metadataIndex()->get("net.minecraft.java");
+        if (versions) {
+            if (versions->isLoaded()) {
+                recommendedJavas = getRecommendedJavaVersionsFromVersionList(versions);
+            } else {
+                auto newTask = versions->getLoadTask();
+                if (newTask) {
+                    connect(newTask.get(), &Task::succeeded, this, [this, versions] {
+                        auto recommendedJavas = getRecommendedJavaVersionsFromVersionList(versions);
+                        for (BasePage* page : container->getPages()) {
+                            pageCast(page)->setRecommendedMajors(recommendedJavas);
+                        }
+                    });
+                    if (!newTask->isRunning())
+                        newTask->start();
+                } else {
+                    recommendedJavas = getRecommendedJavaVersionsFromVersionList(versions);
+                }
+            }
+        }
+    }
+    for (BasePage* page : container->getPages()) {
+        if (page->id() == uid)
+            container->selectPage(page->id());
+
+        auto cast = pageCast(page);
+        cast->setRecomend(true);
+        connect(cast, &InstallJavaPage::selectionChanged, this, [this, cast] { validate(cast); });
+        if (!recommendedJavas.isEmpty()) {
+            cast->setRecommendedMajors(recommendedJavas);
+        }
+    }
+    connect(container, &PageContainer::selectedPageChanged, this, [this](BasePage* previous, BasePage* selected) { validate(selected); });
+    pageCast(container->selectedPage())->selectSearch();
+    validate(container->selectedPage());
+}
+
+QList<BasePage*> InstallDialog::getPages()
+{
+    return {
+        // Mojang
+        new InstallJavaPage("net.minecraft.java", "mojang", tr("Mojang")),
+        // Adoptium
+        new InstallJavaPage("net.adoptium.java", "adoptium", tr("Adoptium")),
+        // Azul
+        new InstallJavaPage("com.azul.java", "azul", tr("Azul Zulu")),
+    };
+}
+
+QString InstallDialog::dialogTitle()
+{
+    return tr("Install Java");
+}
+
+void InstallDialog::validate(BasePage* selected)
+{
+    buttons->button(QDialogButtonBox::Ok)->setEnabled(!!std::dynamic_pointer_cast<Java::Metadata>(pageCast(selected)->selectedVersion()));
+}
+
+void InstallDialog::done(int result)
+{
+    if (result == Accepted) {
+        auto* page = pageCast(container->selectedPage());
+        if (page->selectedVersion()) {
+            auto meta = std::dynamic_pointer_cast<Java::Metadata>(page->selectedVersion());
+            if (meta) {
+                Task::Ptr task;
+                auto final_path = FS::PathCombine(APPLICATION->javaPath(), meta->m_name);
+                auto deletePath = [final_path] { FS::deletePath(final_path); };
+                switch (meta->downloadType) {
+                    case Java::DownloadType::Manifest:
+                        task = makeShared<ManifestDownloadTask>(meta->url, final_path, meta->checksumType, meta->checksumHash);
+                        break;
+                    case Java::DownloadType::Archive:
+                        task = makeShared<ArchiveDownloadTask>(meta->url, final_path, meta->checksumType, meta->checksumHash);
+                        break;
+                    case Java::DownloadType::Unknown:
+                        QString error = QString(tr("Could not determine Java download type!"));
+                        CustomMessageBox::selectable(this, tr("Error"), error, QMessageBox::Warning)->show();
+                        deletePath();
+                }
+                connect(task.get(), &Task::failed, this, [this, &deletePath](QString reason) {
+                    QString error = QString("Java download failed: %1").arg(reason);
+                    CustomMessageBox::selectable(this, tr("Error"), error, QMessageBox::Warning)->show();
+                    deletePath();
+                });
+                connect(task.get(), &Task::aborted, this, deletePath);
+                ProgressDialog pg(this);
+                pg.setSkipButton(true, tr("Abort"));
+                pg.execWithTask(task.get());
+            } else {
+                return;
+            }
+        } else {
+            return;
+        }
+    }
+
+    QDialog::done(result);
+}
+
+}  // namespace Java
+
+#include "InstallJavaDialog.moc"

launcher/ui/java/InstallJavaDialog.h

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <QDialog>
+#include "BaseInstance.h"
+#include "ui/pages/BasePageProvider.h"
+
+class MinecraftInstance;
+class PageContainer;
+class PackProfile;
+class QDialogButtonBox;
+
+namespace Java {
+class InstallDialog final : public QDialog, private BasePageProvider {
+    Q_OBJECT
+
+   public:
+    explicit InstallDialog(const QString& uid = QString(), BaseInstance* instance = nullptr, QWidget* parent = nullptr);
+
+    QList<BasePage*> getPages() override;
+    QString dialogTitle() override;
+
+    void validate(BasePage* selected);
+    void done(int result) override;
+
+   private:
+    PageContainer* container;
+    QDialogButtonBox* buttons;
+};
+}  // namespace Java

launcher/ui/java/VersionList.cpp

@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "VersionList.h"
+
+#include <memory>
+
+#include "BaseVersionList.h"
+#include "SysInfo.h"
+#include "java/JavaMetadata.h"
+#include "meta/VersionList.h"
+
+namespace Java {
+
+VersionList::VersionList(Meta::Version::Ptr version, QObject* parent) : BaseVersionList(parent), m_version(version)
+{
+    if (version->isLoaded())
+        sortVersions();
+}
+
+Task::Ptr VersionList::getLoadTask()
+{
+    auto task = m_version->loadTask(Net::Mode::Online);
+    connect(task.get(), &Task::finished, this, &VersionList::sortVersions);
+    return task;
+}
+
+const BaseVersion::Ptr VersionList::at(int i) const
+{
+    return m_vlist.at(i);
+}
+
+bool VersionList::isLoaded()
+{
+    return m_version->isLoaded();
+}
+
+int VersionList::count() const
+{
+    return m_vlist.count();
+}
+
+QVariant VersionList::data(const QModelIndex& index, int role) const
+{
+    if (!index.isValid())
+        return QVariant();
+
+    if (index.row() > count())
+        return QVariant();
+
+    auto version = (m_vlist[index.row()]);
+    switch (role) {
+        case SortRole:
+            return -index.row();
+        case VersionPointerRole:
+            return QVariant::fromValue(std::dynamic_pointer_cast<BaseVersion>(m_vlist[index.row()]));
+        case VersionIdRole:
+            return version->descriptor();
+        case VersionRole:
+            return version->version.toString();
+        case RecommendedRole:
+            return false;  // do not recommend any version
+        case JavaNameRole:
+            return version->name();
+        case JavaMajorRole: {
+            auto major = version->version.toString();
+            if (major.startsWith("java")) {
+                major = "Java " + major.mid(4);
+            }
+            return major;
+        }
+        case TypeRole:
+            return version->packageType;
+        case Meta::VersionList::TimeRole:
+            return version->releaseTime;
+        default:
+            return QVariant();
+    }
+}
+
+BaseVersionList::RoleList VersionList::providesRoles() const
+{
+    return { VersionPointerRole, VersionIdRole, VersionRole, RecommendedRole, JavaNameRole, TypeRole, Meta::VersionList::TimeRole };
+}
+
+bool sortJavas(BaseVersion::Ptr left, BaseVersion::Ptr right)
+{
+    auto rleft = std::dynamic_pointer_cast<Java::Metadata>(right);
+    auto rright = std::dynamic_pointer_cast<Java::Metadata>(left);
+    return (*rleft) < (*rright);
+}
+
+void VersionList::sortVersions()
+{
+    if (!m_version || !m_version->data())
+        return;
+    QString versionStr = SysInfo::getSupportedJavaArchitecture();
+    beginResetModel();
+    auto runtimes = m_version->data()->runtimes;
+    m_vlist = {};
+    if (!versionStr.isEmpty() && !runtimes.isEmpty()) {
+        std::copy_if(runtimes.begin(), runtimes.end(), std::back_inserter(m_vlist),
+                     [versionStr](Java::MetadataPtr val) { return val->runtimeOS == versionStr; });
+        std::sort(m_vlist.begin(), m_vlist.end(), sortJavas);
+    } else {
+        qWarning() << "No Java versions found for your operating system." << SysInfo::currentSystem() << " " << SysInfo::useQTForArch();
+    }
+    endResetModel();
+}
+
+}  // namespace Java

launcher/ui/java/VersionList.h

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ *  Prism Launcher - Minecraft Launcher
+ *  Copyright (c) 2024 Trial97 <alexandru.tripon97@gmail.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, version 3.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "BaseVersionList.h"
+#include "java/JavaMetadata.h"
+#include "meta/Version.h"
+
+namespace Java {
+
+class VersionList : public BaseVersionList {
+    Q_OBJECT
+
+   public:
+    explicit VersionList(Meta::Version::Ptr m_version, QObject* parent = 0);
+
+    Task::Ptr getLoadTask() override;
+    bool isLoaded() override;
+    const BaseVersion::Ptr at(int i) const override;
+    int count() const override;
+    void sortVersions() override;
+
+    QVariant data(const QModelIndex& index, int role) const override;
+    RoleList providesRoles() const override;
+
+   protected slots:
+    void updateListData(QList<BaseVersion::Ptr>) override {}
+
+   protected:
+    Meta::Version::Ptr m_version;
+    QList<Java::MetadataPtr> m_vlist;
+};
+
+}  // namespace Java

launcher/ui/pages/BasePageProvider.h

@@ -16,7 +16,6 @@
 #pragma once
 
 #include <functional>
-#include <memory>
 #include "ui/pages/BasePage.h"
 
 class BasePageProvider {

launcher/ui/pages/global/JavaPage.cpp

@@ -35,12 +35,18 @@
  */
 
 #include "JavaPage.h"
+#include "BuildConfig.h"
 #include "JavaCommon.h"
+#include "java/JavaInstall.h"
+#include "ui/dialogs/CustomMessageBox.h"
+#include "ui/java/InstallJavaDialog.h"
 #include "ui_JavaPage.h"
 
+#include <QCheckBox>
 #include <QDir>
 #include <QFileDialog>
 #include <QMessageBox>
+#include <QStringListModel>
 #include <QTabBar>
 
 #include "ui/dialogs/VersionSelectDialog.h"
@@ -56,7 +62,22 @@
 JavaPage::JavaPage(QWidget* parent) : QWidget(parent), ui(new Ui::JavaPage)
 {
     ui->setupUi(this);
+
+    if (BuildConfig.JAVA_DOWNLOADER_ENABLED) {
+        ui->managedJavaList->initialize(new JavaInstallList(this, true));
+        ui->managedJavaList->setResizeOn(2);
+        ui->managedJavaList->selectCurrent();
+        ui->managedJavaList->setEmptyString(tr("No managed java versions are installed"));
+        ui->managedJavaList->setEmptyErrorString(tr("Couldn't load the managed java list!"));
+        connect(ui->autodetectJavaCheckBox, &QCheckBox::stateChanged, this, [this] {
+            ui->autodownloadCheckBox->setEnabled(ui->autodetectJavaCheckBox->isChecked());
+            if (!ui->autodetectJavaCheckBox->isChecked())
+                ui->autodownloadCheckBox->setChecked(false);
+        });
+    } else {
+        ui->autodownloadCheckBox->setHidden(true);
         ui->tabWidget->tabBar()->hide();
+    }
 
     loadSettings();
     updateThresholds();
@@ -94,6 +115,8 @@ void JavaPage::applySettings()
     s->set("JvmArgs", ui->jvmArgsTextBox->toPlainText().replace("\n", " "));
     s->set("IgnoreJavaCompatibility", ui->skipCompatibilityCheckbox->isChecked());
     s->set("IgnoreJavaWizard", ui->skipJavaWizardCheckbox->isChecked());
+    s->set("AutomaticJavaSwitch", ui->autodetectJavaCheckBox->isChecked());
+    s->set("AutomaticJavaDownload", ui->autodownloadCheckBox->isChecked());
     JavaCommon::checkJVMArgs(s->get("JvmArgs").toString(), this->parentWidget());
 }
 void JavaPage::loadSettings()
@@ -116,6 +139,8 @@ void JavaPage::loadSettings()
     ui->jvmArgsTextBox->setPlainText(s->get("JvmArgs").toString());
     ui->skipCompatibilityCheckbox->setChecked(s->get("IgnoreJavaCompatibility").toBool());
     ui->skipJavaWizardCheckbox->setChecked(s->get("IgnoreJavaWizard").toBool());
+    ui->autodetectJavaCheckBox->setChecked(s->get("AutomaticJavaSwitch").toBool());
+    ui->autodownloadCheckBox->setChecked(s->get("AutomaticJavaSwitch").toBool() && s->get("AutomaticJavaDownload").toBool());
 }
 
 void JavaPage::on_javaDetectBtn_clicked()
@@ -134,6 +159,14 @@ void JavaPage::on_javaDetectBtn_clicked()
     if (vselect.result() == QDialog::Accepted && vselect.selectedVersion()) {
         java = std::dynamic_pointer_cast<JavaInstall>(vselect.selectedVersion());
         ui->javaPathTextBox->setText(java->path);
+        if (!java->is_64bit && APPLICATION->settings()->get("MaxMemAlloc").toInt() > 2048) {
+            CustomMessageBox::selectable(this, tr("Confirm Selection"),
+                                         tr("You selected a 32-bit version of Java.\n"
+                                            "This installation does not support more than 2048MiB of RAM.\n"
+                                            "Please make sure that the maximum memory value is lower."),
+                                         QMessageBox::Warning, QMessageBox::Ok, QMessageBox::Ok)
+                ->exec();
+        }
     }
 }
 
@@ -166,6 +199,13 @@ void JavaPage::on_javaTestBtn_clicked()
     checker->run();
 }
 
+void JavaPage::on_downloadJavaButton_clicked()
+{
+    auto jdialog = new Java::InstallDialog({}, nullptr, this);
+    jdialog->exec();
+    ui->managedJavaList->loadList();
+}
+
 void JavaPage::on_maxMemSpinBox_valueChanged([[maybe_unused]] int i)
 {
     updateThresholds();
@@ -210,3 +250,35 @@ void JavaPage::updateThresholds()
         ui->labelMaxMemIcon->setPixmap(pix);
     }
 }
+
+void JavaPage::on_removeJavaButton_clicked()
+{
+    auto version = ui->managedJavaList->selectedVersion();
+    auto dcast = std::dynamic_pointer_cast<JavaInstall>(version);
+    if (!dcast) {
+        return;
+    }
+    QDir dir(APPLICATION->javaPath());
+
+    auto entries = dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
+    for (auto& entry : entries) {
+        if (dcast->path.startsWith(entry.canonicalFilePath())) {
+            auto response = CustomMessageBox::selectable(this, tr("Confirm Deletion"),
+                                                         tr("You are about to remove  the Java installation named \"%1\".\n"
+                                                            "Are you sure?")
+                                                             .arg(entry.fileName()),
+                                                         QMessageBox::Warning, QMessageBox::Yes | QMessageBox::No, QMessageBox::No)
+                                ->exec();
+
+            if (response == QMessageBox::Yes) {
+                FS::deletePath(entry.canonicalFilePath());
+                ui->managedJavaList->loadList();
+            }
+            break;
+        }
+    }
+}
+void JavaPage::on_refreshJavaButton_clicked()
+{
+    ui->managedJavaList->loadList();
+}

launcher/ui/pages/global/JavaPage.h

@@ -38,7 +38,7 @@
 #include <Application.h>
 #include <QObjectPtr.h>
 #include <QDialog>
-#include <memory>
+#include <QStringListModel>
 #include "JavaCommon.h"
 #include "ui/pages/BasePage.h"
 
@@ -72,6 +72,9 @@ class JavaPage : public QWidget, public BasePage {
     void on_javaDetectBtn_clicked();
     void on_javaTestBtn_clicked();
     void on_javaBrowseBtn_clicked();
+    void on_downloadJavaButton_clicked();
+    void on_removeJavaButton_clicked();
+    void on_refreshJavaButton_clicked();
     void on_maxMemSpinBox_valueChanged(int i);
     void checkerFinished();
 

launcher/ui/pages/global/JavaPage.ui

@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>545</width>
+    <width>559</width>
-    <height>580</height>
+    <height>659</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -34,9 +34,9 @@
      <property name="currentIndex">
       <number>0</number>
      </property>
-     <widget class="QWidget" name="tab">
+     <widget class="QWidget" name="general">
       <attribute name="title">
-       <string notr="true">Tab 1</string>
+       <string notr="true">General</string>
       </attribute>
       <layout class="QVBoxLayout" name="verticalLayout_2">
        <item>
@@ -160,25 +160,6 @@
           <string>Java Runtime</string>
          </property>
          <layout class="QGridLayout" name="gridLayout_3">
-          <item row="7" column="0" colspan="3">
-           <widget class="QPlainTextEdit" name="jvmArgsTextBox">
-            <property name="enabled">
-             <bool>true</bool>
-            </property>
-            <property name="sizePolicy">
-             <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
-              <horstretch>0</horstretch>
-              <verstretch>0</verstretch>
-             </sizepolicy>
-            </property>
-            <property name="maximumSize">
-             <size>
-              <width>16777215</width>
-              <height>100</height>
-             </size>
-            </property>
-           </widget>
-          </item>
           <item row="4" column="0">
            <widget class="QCheckBox" name="skipCompatibilityCheckbox">
             <property name="sizePolicy">
@@ -225,7 +206,7 @@
             </item>
            </layout>
           </item>
-          <item row="6" column="0">
+          <item row="8" column="0">
            <widget class="QLabel" name="labelJVMArgs">
             <property name="sizePolicy">
              <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
@@ -241,6 +222,45 @@
             </property>
            </widget>
           </item>
+          <item row="5" column="0">
+           <widget class="QCheckBox" name="skipJavaWizardCheckbox">
+            <property name="toolTip">
+             <string>If enabled, the launcher will not prompt you to choose a Java version if one isn't found.</string>
+            </property>
+            <property name="text">
+             <string>Skip Java &amp;Wizard</string>
+            </property>
+           </widget>
+          </item>
+          <item row="9" column="0" colspan="3">
+           <widget class="QPlainTextEdit" name="jvmArgsTextBox">
+            <property name="enabled">
+             <bool>true</bool>
+            </property>
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="maximumSize">
+             <size>
+              <width>16777215</width>
+              <height>100</height>
+             </size>
+            </property>
+           </widget>
+          </item>
+          <item row="6" column="0">
+           <widget class="QCheckBox" name="autodetectJavaCheckBox">
+            <property name="toolTip">
+             <string>Automatically selects the Java version that is compatible with the current Minecraft instance, based on the major version required.</string>
+            </property>
+            <property name="text">
+             <string>Autodetect Java version</string>
+            </property>
+           </widget>
+          </item>
           <item row="1" column="0" colspan="3">
            <layout class="QHBoxLayout" name="horizontalLayout">
             <item>
@@ -277,13 +297,16 @@
             </item>
            </layout>
           </item>
-          <item row="5" column="0">
+          <item row="7" column="0">
-           <widget class="QCheckBox" name="skipJavaWizardCheckbox">
+           <widget class="QCheckBox" name="autodownloadCheckBox">
+            <property name="enabled">
+             <bool>false</bool>
+            </property>
             <property name="toolTip">
-             <string>If enabled, the launcher will not prompt you to choose a Java version if one isn't found.</string>
+             <string>Automatically downloads and selects the Java version recommended by Mojang.</string>
             </property>
             <property name="text">
-             <string>Skip Java &amp;Wizard</string>
+             <string>Auto-download Mojang Java</string>
             </property>
            </widget>
           </item>
@@ -305,16 +328,106 @@
        </item>
       </layout>
      </widget>
+     <widget class="QWidget" name="management">
+      <attribute name="title">
+       <string>Management</string>
+      </attribute>
+      <layout class="QVBoxLayout" name="verticalLayout_3">
+       <item>
+        <widget class="QGroupBox" name="groupBox">
+         <property name="title">
+          <string>Downloaded Java Versions</string>
+         </property>
+         <layout class="QHBoxLayout" name="horizontalLayout_4">
+          <item>
+           <widget class="VersionSelectWidget" name="managedJavaList" native="true">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <layout class="QVBoxLayout" name="managedJavaBtnLayout">
+            <item>
+             <widget class="QPushButton" name="downloadJavaButton">
+              <property name="text">
+               <string>Download</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="removeJavaButton">
+              <property name="text">
+               <string>Remove</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="verticalSpacer_2">
+              <property name="orientation">
+               <enum>Qt::Vertical</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>20</width>
+                <height>40</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <widget class="QPushButton" name="refreshJavaButton">
+              <property name="text">
+               <string>Refresh</string>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item>
+        <spacer name="managementSpacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>20</width>
+           <height>40</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+      </layout>
+     </widget>
     </widget>
    </item>
   </layout>
  </widget>
+ <customwidgets>
+  <customwidget>
+   <class>VersionSelectWidget</class>
+   <extends>QWidget</extends>
+   <header>ui/widgets/VersionSelectWidget.h</header>
+   <container>1</container>
+  </customwidget>
+ </customwidgets>
  <tabstops>
   <tabstop>minMemSpinBox</tabstop>
   <tabstop>maxMemSpinBox</tabstop>
   <tabstop>permGenSpinBox</tabstop>
-  <tabstop>javaBrowseBtn</tabstop>
   <tabstop>javaPathTextBox</tabstop>
+  <tabstop>javaBrowseBtn</tabstop>
+  <tabstop>javaDetectBtn</tabstop>
+  <tabstop>javaTestBtn</tabstop>
+  <tabstop>skipCompatibilityCheckbox</tabstop>
+  <tabstop>skipJavaWizardCheckbox</tabstop>
+  <tabstop>jvmArgsTextBox</tabstop>
   <tabstop>tabWidget</tabstop>
  </tabstops>
  <resources/>

launcher/ui/pages/global/LauncherPage.cpp

@@ -173,6 +173,16 @@ void LauncherPage::on_downloadsDirBrowseBtn_clicked()
     }
 }
 
+void LauncherPage::on_javaDirBrowseBtn_clicked()
+{
+    QString raw_dir = QFileDialog::getExistingDirectory(this, tr("Java Folder"), ui->javaDirTextBox->text());
+
+    if (!raw_dir.isEmpty() && QDir(raw_dir).exists()) {
+        QString cooked_dir = FS::NormalizePath(raw_dir);
+        ui->javaDirTextBox->setText(cooked_dir);
+    }
+}
+
 void LauncherPage::on_skinsDirBrowseBtn_clicked()
 {
     QString raw_dir = QFileDialog::getExistingDirectory(this, tr("Skins Folder"), ui->skinsDirTextBox->text());
@@ -223,6 +233,7 @@ void LauncherPage::applySettings()
     s->set("IconsDir", ui->iconsDirTextBox->text());
     s->set("DownloadsDir", ui->downloadsDirTextBox->text());
     s->set("SkinsDir", ui->skinsDirTextBox->text());
+    s->set("JavaDir", ui->javaDirTextBox->text());
     s->set("DownloadsDirWatchRecursive", ui->downloadsDirWatchRecursiveCheckBox->isChecked());
 
     auto sortMode = (InstSortMode)ui->sortingModeGroup->checkedId();
@@ -289,6 +300,7 @@ void LauncherPage::loadSettings()
     ui->iconsDirTextBox->setText(s->get("IconsDir").toString());
     ui->downloadsDirTextBox->setText(s->get("DownloadsDir").toString());
     ui->skinsDirTextBox->setText(s->get("SkinsDir").toString());
+    ui->javaDirTextBox->setText(s->get("JavaDir").toString());
     ui->downloadsDirWatchRecursiveCheckBox->setChecked(s->get("DownloadsDirWatchRecursive").toBool());
 
     QString sortMode = s->get("InstSortMode").toString();

launcher/ui/pages/global/LauncherPage.h

@@ -73,6 +73,7 @@ class LauncherPage : public QWidget, public BasePage {
     void on_modsDirBrowseBtn_clicked();
     void on_iconsDirBrowseBtn_clicked();
     void on_downloadsDirBrowseBtn_clicked();
+    void on_javaDirBrowseBtn_clicked();
     void on_skinsDirBrowseBtn_clicked();
     void on_metadataDisableBtn_clicked();
 

launcher/ui/pages/global/LauncherPage.ui

@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>511</width>
-    <height>691</height>
+    <height>726</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -94,7 +94,7 @@
           <string>Folders</string>
          </property>
          <layout class="QGridLayout" name="foldersBoxLayout">
-          <item row="4" column="0">
+          <item row="8" column="0">
            <widget class="QLabel" name="labelDownloadsDir">
             <property name="text">
              <string>&amp;Downloads:</string>
@@ -104,42 +104,59 @@
             </property>
            </widget>
           </item>
-          <item row="0" column="0">
+          <item row="8" column="2">
-           <widget class="QLabel" name="labelInstDir">
-            <property name="text">
-             <string>I&amp;nstances:</string>
-            </property>
-            <property name="buddy">
-             <cstring>instDirTextBox</cstring>
-            </property>
-           </widget>
-          </item>
-          <item row="0" column="1">
-           <widget class="QLineEdit" name="instDirTextBox"/>
-          </item>
-          <item row="4" column="1">
-           <widget class="QLineEdit" name="downloadsDirTextBox"/>
-          </item>
-          <item row="2" column="1">
-           <widget class="QLineEdit" name="iconsDirTextBox"/>
-          </item>
-          <item row="3" column="1">
-           <widget class="QLineEdit" name="skinsDirTextBox"/>
-          </item>
-          <item row="4" column="2">
            <widget class="QToolButton" name="downloadsDirBrowseBtn">
             <property name="text">
              <string>Browse</string>
             </property>
            </widget>
           </item>
-          <item row="1" column="1">
+          <item row="2" column="1">
-           <widget class="QLineEdit" name="modsDirTextBox"/>
+           <widget class="QLineEdit" name="iconsDirTextBox"/>
           </item>
-          <item row="1" column="2">
+          <item row="3" column="1">
-           <widget class="QToolButton" name="modsDirBrowseBtn">
+           <widget class="QLineEdit" name="javaDirTextBox"/>
+          </item>
+          <item row="4" column="0">
+           <widget class="QLabel" name="labelSkinsDir">
             <property name="text">
-             <string>Browse</string>
+             <string>&amp;Skins:</string>
+            </property>
+            <property name="buddy">
+             <cstring>skinsDirTextBox</cstring>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="0">
+           <widget class="QLabel" name="labelIconsDir">
+            <property name="text">
+             <string>&amp;Icons:</string>
+            </property>
+            <property name="buddy">
+             <cstring>iconsDirTextBox</cstring>
+            </property>
+           </widget>
+          </item>
+          <item row="9" column="1" colspan="2">
+           <widget class="QCheckBox" name="downloadsDirWatchRecursiveCheckBox">
+            <property name="toolTip">
+             <string>When enabled, in addition to the downloads folder, its sub folders will also be searched when looking for resources (e.g. when looking for blocked mods on CurseForge).</string>
+            </property>
+            <property name="text">
+             <string>Check downloads folder recursively</string>
+            </property>
+           </widget>
+          </item>
+          <item row="8" column="1">
+           <widget class="QLineEdit" name="downloadsDirTextBox"/>
+          </item>
+          <item row="3" column="0">
+           <widget class="QLabel" name="labelJavaDir">
+            <property name="text">
+             <string>&amp;Java:</string>
+            </property>
+            <property name="buddy">
+             <cstring>javaDirTextBox</cstring>
             </property>
            </widget>
           </item>
@@ -153,6 +170,22 @@
             </property>
            </widget>
           </item>
+          <item row="4" column="1">
+           <widget class="QLineEdit" name="skinsDirTextBox"/>
+          </item>
+          <item row="1" column="1">
+           <widget class="QLineEdit" name="modsDirTextBox"/>
+          </item>
+          <item row="0" column="1">
+           <widget class="QLineEdit" name="instDirTextBox"/>
+          </item>
+          <item row="1" column="2">
+           <widget class="QToolButton" name="modsDirBrowseBtn">
+            <property name="text">
+             <string>Browse</string>
+            </property>
+           </widget>
+          </item>
           <item row="0" column="2">
            <widget class="QToolButton" name="instDirBrowseBtn">
             <property name="text">
@@ -167,40 +200,27 @@
             </property>
            </widget>
           </item>
-          <item row="2" column="0">
+          <item row="0" column="0">
-           <widget class="QLabel" name="labelIconsDir">
+           <widget class="QLabel" name="labelInstDir">
             <property name="text">
-             <string>&amp;Icons:</string>
+             <string>I&amp;nstances:</string>
             </property>
             <property name="buddy">
-             <cstring>iconsDirTextBox</cstring>
+             <cstring>instDirTextBox</cstring>
             </property>
            </widget>
           </item>
           <item row="3" column="2">
-           <widget class="QToolButton" name="skinsDirBrowseBtn">
+           <widget class="QToolButton" name="javaDirBrowseBtn">
             <property name="text">
              <string>Browse</string>
             </property>
            </widget>
           </item>
-          <item row="3" column="0">
+          <item row="4" column="2">
-           <widget class="QLabel" name="labelSkinsDir">
+           <widget class="QToolButton" name="skinsDirBrowseBtn">
             <property name="text">
-             <string>&amp;Skins:</string>
+             <string>Browse</string>
-            </property>
-            <property name="buddy">
-             <cstring>skinsDirTextBox</cstring>
-            </property>
-           </widget>
-          </item>
-          <item row="5" column="1" colspan="2">
-           <widget class="QCheckBox" name="downloadsDirWatchRecursiveCheckBox">
-            <property name="toolTip">
-             <string>When enabled, in addition to the downloads folder, its sub folders will also be searched when looking for resources (e.g. when looking for blocked mods on CurseForge).</string>
-            </property>
-            <property name="text">
-             <string>Check downloads folder recursively</string>
             </property>
            </widget>
           </item>

launcher/ui/pages/instance/InstanceSettingsPage.cpp

@@ -38,6 +38,9 @@
 #include "InstanceSettingsPage.h"
 #include "minecraft/MinecraftInstance.h"
 #include "minecraft/WorldList.h"
+#include "settings/Setting.h"
+#include "ui/dialogs/CustomMessageBox.h"
+#include "ui/java/InstallJavaDialog.h"
 #include "ui_InstanceSettingsPage.h"
 
 #include <QDialog>
@@ -64,6 +67,8 @@ InstanceSettingsPage::InstanceSettingsPage(BaseInstance* inst, QWidget* parent)
     m_settings = inst->settings();
     ui->setupUi(this);
 
+    ui->javaDownloadBtn->setHidden(!BuildConfig.JAVA_DOWNLOADER_ENABLED);
+
     connect(ui->openGlobalJavaSettingsButton, &QCommandLinkButton::clicked, this, &InstanceSettingsPage::globalSettingsButtonClicked);
     connect(APPLICATION, &Application::globalSettingsAboutToOpen, this, &InstanceSettingsPage::applySettings);
     connect(APPLICATION, &Application::globalSettingsClosed, this, &InstanceSettingsPage::loadSettings);
@@ -204,9 +209,6 @@ void InstanceSettingsPage::applySettings()
         m_settings->reset("JvmArgs");
     }
 
-    // old generic 'override both' is removed.
-    m_settings->reset("OverrideJava");
-
     // Custom Commands
     bool custcmd = ui->customCommands->checked();
     m_settings->set("OverrideCommands", custcmd);
@@ -342,10 +344,11 @@ void InstanceSettingsPage::loadSettings()
     ui->labelPermgenNote->setVisible(permGenVisible);
 
     // Java Settings
-    bool overrideJava = m_settings->get("OverrideJava").toBool();
+    bool overrideLocation = m_settings->get("OverrideJavaLocation").toBool();
-    bool overrideLocation = m_settings->get("OverrideJavaLocation").toBool() || overrideJava;
+    bool overrideArgs = m_settings->get("OverrideJavaArgs").toBool();
-    bool overrideArgs = m_settings->get("OverrideJavaArgs").toBool() || overrideJava;
 
+    connect(m_settings->getSetting("OverrideJavaLocation").get(), &Setting::SettingChanged, ui->javaSettingsGroupBox,
+            [this] { ui->javaSettingsGroupBox->setChecked(m_settings->get("OverrideJavaLocation").toBool()); });
     ui->javaSettingsGroupBox->setChecked(overrideLocation);
     ui->javaPathTextBox->setText(m_settings->get("JavaPath").toString());
     ui->skipCompatibilityCheckbox->setChecked(m_settings->get("IgnoreJavaCompatibility").toBool());
@@ -431,6 +434,12 @@ void InstanceSettingsPage::loadSettings()
     ui->onlineFixes->setChecked(m_settings->get("OnlineFixes").toBool());
 }
 
+void InstanceSettingsPage::on_javaDownloadBtn_clicked()
+{
+    auto jdialog = new Java::InstallDialog({}, m_instance, this);
+    jdialog->exec();
+}
+
 void InstanceSettingsPage::on_javaDetectBtn_clicked()
 {
     if (JavaUtils::getJavaCheckPath().isEmpty()) {
@@ -452,6 +461,15 @@ void InstanceSettingsPage::on_javaDetectBtn_clicked()
         ui->labelPermGen->setVisible(visible);
         ui->labelPermgenNote->setVisible(visible);
         m_settings->set("PermGenVisible", visible);
+
+        if (!java->is_64bit && m_settings->get("MaxMemAlloc").toInt() > 2048) {
+            CustomMessageBox::selectable(this, tr("Confirm Selection"),
+                                         tr("You selected a 32-bit version of Java.\n"
+                                            "This installation does not support more than 2048MiB of RAM.\n"
+                                            "Please make sure that the maximum memory value is lower."),
+                                         QMessageBox::Warning, QMessageBox::Ok, QMessageBox::Ok)
+                ->exec();
+        }
     }
 }
 

launcher/ui/pages/instance/InstanceSettingsPage.h

@@ -69,6 +69,7 @@ class InstanceSettingsPage : public QWidget, public BasePage {
     void on_javaDetectBtn_clicked();
     void on_javaTestBtn_clicked();
     void on_javaBrowseBtn_clicked();
+    void on_javaDownloadBtn_clicked();
     void on_maxMemSpinBox_valueChanged(int i);
     void on_serverJoinAddressButton_toggled(bool checked);
     void on_worldJoinButton_toggled(bool checked);

launcher/ui/pages/instance/InstanceSettingsPage.ui

@@ -84,6 +84,13 @@
           </item>
           <item row="2" column="0">
            <layout class="QHBoxLayout" name="horizontalLayout_2">
+            <item>
+             <widget class="QPushButton" name="javaDownloadBtn">
+              <property name="text">
+               <string>Download Java</string>
+              </property>
+             </widget>
+            </item>
             <item>
              <widget class="QPushButton" name="javaDetectBtn">
               <property name="text">
@@ -764,6 +771,12 @@
   <tabstop>openGlobalJavaSettingsButton</tabstop>
   <tabstop>settingsTabs</tabstop>
   <tabstop>javaSettingsGroupBox</tabstop>
+  <tabstop>javaPathTextBox</tabstop>
+  <tabstop>javaBrowseBtn</tabstop>
+  <tabstop>javaDownloadBtn</tabstop>
+  <tabstop>javaDetectBtn</tabstop>
+  <tabstop>javaTestBtn</tabstop>
+  <tabstop>skipCompatibilityCheckbox</tabstop>
   <tabstop>memoryGroupBox</tabstop>
   <tabstop>minMemSpinBox</tabstop>
   <tabstop>maxMemSpinBox</tabstop>
@@ -783,6 +796,18 @@
   <tabstop>useNativeOpenALCheck</tabstop>
   <tabstop>showGameTime</tabstop>
   <tabstop>recordGameTime</tabstop>
+  <tabstop>miscellaneousSettingsBox</tabstop>
+  <tabstop>closeAfterLaunchCheck</tabstop>
+  <tabstop>quitAfterGameStopCheck</tabstop>
+  <tabstop>perfomanceGroupBox</tabstop>
+  <tabstop>enableFeralGamemodeCheck</tabstop>
+  <tabstop>enableMangoHud</tabstop>
+  <tabstop>useDiscreteGpuCheck</tabstop>
+  <tabstop>gameTimeGroupBox</tabstop>
+  <tabstop>serverJoinGroupBox</tabstop>
+  <tabstop>serverJoinAddress</tabstop>
+  <tabstop>instanceAccountGroupBox</tabstop>
+  <tabstop>instanceAccountSelector</tabstop>
  </tabstops>
  <resources/>
  <connections/>

launcher/ui/pages/instance/VersionPage.cpp

@@ -393,6 +393,11 @@ void VersionPage::on_actionChange_version_triggered()
     bool important = false;
     if (uid == "net.minecraft") {
         important = true;
+        if (APPLICATION->settings()->get("AutomaticJavaSwitch").toBool() && m_inst->settings()->get("AutomaticJava").toBool() &&
+            m_inst->settings()->get("OverrideJavaLocation").toBool()) {
+            m_inst->settings()->set("OverrideJavaLocation", false);
+            m_inst->settings()->set("JavaPath", "");
+        }
     }
     m_profile->setComponentVersion(uid, vselect.selectedVersion()->descriptor(), important);
     m_profile->resolve(Net::Mode::Online);

launcher/ui/setupwizard/JavaWizardPage.cpp

@@ -12,12 +12,8 @@
 
 #include <sys.h>
 
-#include "FileSystem.h"
 #include "JavaCommon.h"
-#include "java/JavaInstall.h"
-#include "java/JavaUtils.h"
 
-#include "ui/dialogs/CustomMessageBox.h"
 #include "ui/widgets/JavaSettingsWidget.h"
 #include "ui/widgets/VersionSelectWidget.h"
 
@@ -57,6 +53,8 @@ bool JavaWizardPage::validatePage()
 {
     auto settings = APPLICATION->settings();
     auto result = m_java_widget->validate();
+    settings->set("AutomaticJavaSwitch", m_java_widget->autoDetectJava());
+    settings->set("AutomaticJavaDownload", m_java_widget->autoDownloadJava());
     switch (result) {
         default:
         case JavaSettingsWidget::ValidationStatus::Bad: {

launcher/ui/widgets/JavaSettingsWidget.cpp

@@ -4,6 +4,7 @@
 #include <QGroupBox>
 #include <QLabel>
 #include <QLineEdit>
+#include <QMessageBox>
 #include <QPushButton>
 #include <QSpinBox>
 #include <QToolButton>
@@ -11,12 +12,16 @@
 
 #include <sys.h>
 
+#include "DesktopServices.h"
 #include "FileSystem.h"
 #include "JavaCommon.h"
+#include "java/JavaChecker.h"
 #include "java/JavaInstall.h"
+#include "java/JavaInstallList.h"
 #include "java/JavaUtils.h"
 
 #include "ui/dialogs/CustomMessageBox.h"
+#include "ui/java/InstallJavaDialog.h"
 #include "ui/widgets/VersionSelectWidget.h"
 
 #include "Application.h"
@@ -38,6 +43,9 @@ JavaSettingsWidget::JavaSettingsWidget(QWidget* parent) : QWidget(parent)
     connect(m_javaBrowseBtn, &QPushButton::clicked, this, &JavaSettingsWidget::on_javaBrowseBtn_clicked);
     connect(m_javaPathTextBox, &QLineEdit::textEdited, this, &JavaSettingsWidget::javaPathEdited);
     connect(m_javaStatusBtn, &QToolButton::clicked, this, &JavaSettingsWidget::on_javaStatusBtn_clicked);
+    if (BuildConfig.JAVA_DOWNLOADER_ENABLED) {
+        connect(m_javaDownloadBtn, &QPushButton::clicked, this, &JavaSettingsWidget::javaDownloadBtn_clicked);
+    }
 }
 
 void JavaSettingsWidget::setupUi()
@@ -120,6 +128,38 @@ void JavaSettingsWidget::setupUi()
 
     m_verticalLayout->addWidget(m_memoryGroupBox);
 
+    m_horizontalBtnLayout = new QHBoxLayout();
+    m_horizontalBtnLayout->setObjectName(QStringLiteral("horizontalBtnLayout"));
+
+    if (BuildConfig.JAVA_DOWNLOADER_ENABLED) {
+        m_javaDownloadBtn = new QPushButton(tr("Download Java"), this);
+        m_horizontalBtnLayout->addWidget(m_javaDownloadBtn);
+    }
+
+    m_verticalLayout->addLayout(m_horizontalBtnLayout);
+
+    m_autoJavaGroupBox = new QGroupBox(this);
+    m_autoJavaGroupBox->setObjectName(QStringLiteral("autoJavaGroupBox"));
+    m_veriticalJavaLayout = new QVBoxLayout(m_autoJavaGroupBox);
+    m_veriticalJavaLayout->setObjectName(QStringLiteral("veriticalJavaLayout"));
+
+    m_autodetectJavaCheckBox = new QCheckBox(m_autoJavaGroupBox);
+    m_autodetectJavaCheckBox->setObjectName("autodetectJavaCheckBox");
+    m_veriticalJavaLayout->addWidget(m_autodetectJavaCheckBox);
+
+    if (BuildConfig.JAVA_DOWNLOADER_ENABLED) {
+        m_autodownloadCheckBox = new QCheckBox(m_autoJavaGroupBox);
+        m_autodownloadCheckBox->setObjectName("autodownloadCheckBox");
+        m_autodownloadCheckBox->setEnabled(false);
+        m_veriticalJavaLayout->addWidget(m_autodownloadCheckBox);
+        connect(m_autodetectJavaCheckBox, &QCheckBox::stateChanged, this, [this] {
+            m_autodownloadCheckBox->setEnabled(m_autodetectJavaCheckBox->isChecked());
+            if (!m_autodetectJavaCheckBox->isChecked())
+                m_autodownloadCheckBox->setChecked(false);
+        });
+    }
+    m_verticalLayout->addWidget(m_autoJavaGroupBox);
+
     retranslate();
 }
 
@@ -137,6 +177,19 @@ void JavaSettingsWidget::initialize()
     m_maxMemSpinBox->setValue(observedMaxMemory);
     m_permGenSpinBox->setValue(observedPermGenMemory);
     updateThresholds();
+
+    if (BuildConfig.JAVA_DOWNLOADER_ENABLED) {
+        auto button =
+            CustomMessageBox::selectable(this, tr("Automatic Java Download"),
+                                         tr("%1 can automatically download the correct Java version for each version of Minecraft..\n"
+                                            "Do you want to enable Java auto-download?\n")
+                                             .arg(BuildConfig.LAUNCHER_DISPLAYNAME),
+                                         QMessageBox::Question, QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes)
+                ->exec();
+        auto checked = button == QMessageBox::Yes;
+        m_autodetectJavaCheckBox->setChecked(checked);
+        m_autodownloadCheckBox->setChecked(checked);
+    }
 }
 
 void JavaSettingsWidget::refresh()
@@ -153,21 +206,53 @@ JavaSettingsWidget::ValidationStatus JavaSettingsWidget::validate()
     switch (javaStatus) {
         default:
         case JavaStatus::NotSet:
+            /* fallthrough */
         case JavaStatus::DoesNotExist:
+            /* fallthrough */
         case JavaStatus::DoesNotStart:
+            /* fallthrough */
         case JavaStatus::ReturnedInvalidData: {
-            int button = CustomMessageBox::selectable(this, tr("No Java version selected"),
+            if (!(BuildConfig.JAVA_DOWNLOADER_ENABLED && m_autodownloadCheckBox->isChecked())) {  // the java will not be autodownloaded
-                                                      tr("You didn't select a Java version or selected something that doesn't work.\n"
+                int button = QMessageBox::No;
+                if (m_result.mojangPlatform == "32" && maxHeapSize() > 2048) {
+                    button = CustomMessageBox::selectable(
+                                 this, tr("32-bit Java detected"),
+                                 tr("You selected a 32-bit installation of Java, but allocated more than 2048MiB as maximum memory.\n"
                                     "%1 will not be able to start Minecraft.\n"
-                                                         "Do you wish to proceed without any Java?"
+                                    "Do you wish to proceed?"
                                     "\n\n"
                                     "You can change the Java version in the settings later.\n")
                                      .arg(BuildConfig.LAUNCHER_DISPLAYNAME),
-                                                      QMessageBox::Warning, QMessageBox::Yes | QMessageBox::No, QMessageBox::NoButton)
+                                 QMessageBox::Warning, QMessageBox::Yes | QMessageBox::No | QMessageBox::Help, QMessageBox::NoButton)
                                  ->exec();
+
+                } else {
+                    button = CustomMessageBox::selectable(this, tr("No Java version selected"),
+                                                          tr("You either didn't select a Java version or selected one that does not work.\n"
+                                                             "%1 will not be able to start Minecraft.\n"
+                                                             "Do you wish to proceed without a functional version of Java?"
+                                                             "\n\n"
+                                                             "You can change the Java version in the settings later.\n")
+                                                              .arg(BuildConfig.LAUNCHER_DISPLAYNAME),
+                                                          QMessageBox::Warning, QMessageBox::Yes | QMessageBox::No | QMessageBox::Help,
+                                                          QMessageBox::NoButton)
+                                 ->exec();
+                }
+                switch (button) {
+                    case QMessageBox::Yes:
+                        return ValidationStatus::JavaBad;
+                    case QMessageBox::Help:
+                        DesktopServices::openUrl(QUrl(BuildConfig.HELP_URL.arg("java-wizard")));
+                    /* fallthrough */
+                    case QMessageBox::No:
+                    /* fallthrough */
+                    default:
+                        return ValidationStatus::Bad;
+                }
                 if (button == QMessageBox::No) {
                     return ValidationStatus::Bad;
                 }
+            }
             return ValidationStatus::JavaBad;
         } break;
         case JavaStatus::Pending: {
@@ -250,21 +335,22 @@ void JavaSettingsWidget::javaVersionSelected(BaseVersion::Ptr version)
 
 void JavaSettingsWidget::on_javaBrowseBtn_clicked()
 {
-    QString filter;
+    auto filter = QString("Java (%1)").arg(JavaUtils::javaExecutable);
-#if defined Q_OS_WIN32
+    auto raw_path = QFileDialog::getOpenFileName(this, tr("Find Java executable"), QString(), filter);
-    filter = "Java (javaw.exe)";
-#else
-    filter = "Java (java)";
-#endif
-    QString raw_path = QFileDialog::getOpenFileName(this, tr("Find Java executable"), QString(), filter);
     if (raw_path.isEmpty()) {
         return;
     }
-    QString cooked_path = FS::NormalizePath(raw_path);
+    auto cooked_path = FS::NormalizePath(raw_path);
     m_javaPathTextBox->setText(cooked_path);
     checkJavaPath(cooked_path);
 }
 
+void JavaSettingsWidget::javaDownloadBtn_clicked()
+{
+    auto jdialog = new Java::InstallDialog({}, nullptr, this);
+    jdialog->exec();
+}
+
 void JavaSettingsWidget::on_javaStatusBtn_clicked()
 {
     QString text;
@@ -359,30 +445,25 @@ void JavaSettingsWidget::checkJavaPath(const QString& path)
         return;
     }
     setJavaStatus(JavaStatus::Pending);
-    m_checker.reset(new JavaChecker());
+    m_checker.reset(
-    m_checker->m_path = path;
+        new JavaChecker(path, "", minHeapSize(), maxHeapSize(), m_permGenSpinBox->isVisible() ? m_permGenSpinBox->value() : 0, 0, this));
-    m_checker->m_minMem = minHeapSize();
-    m_checker->m_maxMem = maxHeapSize();
-    if (m_permGenSpinBox->isVisible()) {
-        m_checker->m_permGen = m_permGenSpinBox->value();
-    }
     connect(m_checker.get(), &JavaChecker::checkFinished, this, &JavaSettingsWidget::checkFinished);
-    m_checker->performCheck();
+    m_checker->start();
 }
 
-void JavaSettingsWidget::checkFinished(JavaCheckResult result)
+void JavaSettingsWidget::checkFinished(const JavaChecker::Result& result)
 {
     m_result = result;
     switch (result.validity) {
-        case JavaCheckResult::Validity::Valid: {
+        case JavaChecker::Result::Validity::Valid: {
             setJavaStatus(JavaStatus::Good);
             break;
         }
-        case JavaCheckResult::Validity::ReturnedInvalidData: {
+        case JavaChecker::Result::Validity::ReturnedInvalidData: {
             setJavaStatus(JavaStatus::ReturnedInvalidData);
             break;
         }
-        case JavaCheckResult::Validity::Errored: {
+        case JavaChecker::Result::Validity::Errored: {
             setJavaStatus(JavaStatus::DoesNotStart);
             break;
         }
@@ -403,6 +484,11 @@ void JavaSettingsWidget::retranslate()
     m_minMemSpinBox->setToolTip(tr("The amount of memory Minecraft is started with."));
     m_permGenSpinBox->setToolTip(tr("The amount of memory available to store loaded Java classes."));
     m_javaBrowseBtn->setText(tr("Browse"));
+    if (BuildConfig.JAVA_DOWNLOADER_ENABLED) {
+        m_autodownloadCheckBox->setText(tr("Auto-download Mojang Java"));
+    }
+    m_autodetectJavaCheckBox->setText(tr("Autodetect Java version"));
+    m_autoJavaGroupBox->setTitle(tr("Autodetect Java"));
 }
 
 void JavaSettingsWidget::updateThresholds()
@@ -418,6 +504,9 @@ void JavaSettingsWidget::updateThresholds()
     } else if (observedMaxMemory < observedMinMemory) {
         iconName = "status-yellow";
         m_labelMaxMemIcon->setToolTip(tr("Your maximum memory allocation is smaller than the minimum value"));
+    } else if (observedMaxMemory > 2048 && m_result.is_64bit) {
+        iconName = "status-bad";
+        m_labelMaxMemIcon->setToolTip(tr("You are exceeding the maximum allocation supported by 32-bit installations of Java."));
     } else {
         iconName = "status-good";
         m_labelMaxMemIcon->setToolTip("");
@@ -430,3 +519,13 @@ void JavaSettingsWidget::updateThresholds()
         m_labelMaxMemIcon->setPixmap(pix);
     }
 }
+
+bool JavaSettingsWidget::autoDownloadJava() const
+{
+    return m_autodownloadCheckBox && m_autodownloadCheckBox->isChecked();
+}
+
+bool JavaSettingsWidget::autoDetectJava() const
+{
+    return m_autodetectJavaCheckBox->isChecked();
+}

launcher/ui/widgets/JavaSettingsWidget.h

@@ -4,6 +4,7 @@
 #include <BaseVersion.h>
 #include <QObjectPtr.h>
 #include <java/JavaChecker.h>
+#include <qcheckbox.h>
 #include <QIcon>
 
 class QLineEdit;
@@ -25,7 +26,7 @@ class JavaSettingsWidget : public QWidget {
 
    public:
     explicit JavaSettingsWidget(QWidget* parent);
-    virtual ~JavaSettingsWidget() {};
+    virtual ~JavaSettingsWidget() = default;
 
     enum class JavaStatus { NotSet, Pending, Good, DoesNotExist, DoesNotStart, ReturnedInvalidData } javaStatus = JavaStatus::NotSet;
 
@@ -41,6 +42,8 @@ class JavaSettingsWidget : public QWidget {
     int minHeapSize() const;
     int maxHeapSize() const;
     QString javaPath() const;
+    bool autoDetectJava() const;
+    bool autoDownloadJava() const;
 
     void updateThresholds();
 
@@ -50,7 +53,8 @@ class JavaSettingsWidget : public QWidget {
     void javaVersionSelected(BaseVersion::Ptr version);
     void on_javaBrowseBtn_clicked();
     void on_javaStatusBtn_clicked();
-    void checkFinished(JavaCheckResult result);
+    void javaDownloadBtn_clicked();
+    void checkFinished(const JavaChecker::Result& result);
 
    protected: /* methods */
     void checkJavaPathOnEdit(const QString& path);
@@ -76,15 +80,23 @@ class JavaSettingsWidget : public QWidget {
     QSpinBox* m_minMemSpinBox = nullptr;
     QLabel* m_labelPermGen = nullptr;
     QSpinBox* m_permGenSpinBox = nullptr;
+
+    QHBoxLayout* m_horizontalBtnLayout = nullptr;
+    QPushButton* m_javaDownloadBtn = nullptr;
     QIcon goodIcon;
     QIcon yellowIcon;
     QIcon badIcon;
 
+    QGroupBox* m_autoJavaGroupBox = nullptr;
+    QVBoxLayout* m_veriticalJavaLayout = nullptr;
+    QCheckBox* m_autodetectJavaCheckBox = nullptr;
+    QCheckBox* m_autodownloadCheckBox = nullptr;
+
     unsigned int observedMinMemory = 0;
     unsigned int observedMaxMemory = 0;
     unsigned int observedPermGenMemory = 0;
     QString queuedCheck;
     uint64_t m_availableMemory = 0ull;
     shared_qobject_ptr<JavaChecker> m_checker;
-    JavaCheckResult m_result;
+    JavaChecker::Result m_result;
 };