fix: issue with 64 bit OS not using correct runtime when using 32 bit Java

.vscode/launch.json

@@ -10,7 +10,7 @@
             "cwd": "${workspaceFolder}/testLauncher",
             "preLaunchTask": "makeTestLauncherDirectory",
             "args": "--debug --debug-level 5 --disable-error-reporting --no-launcher-update",
-            
+
         },
         {
             "type": "java",

CHANGELOG.md

@@ -10,5 +10,6 @@ This changelog only contains the changes that are unreleased. For changes for in
 
 ### Fixes
 - Update the LaunchServer.bat script to make it "simpler" to change Java path
+- Issue with 64 bit OS not using correct runtime when using 32 bit Java
 
 ### Misc

src/main/java/com/atlauncher/App.java

@@ -425,7 +425,7 @@ public class App {
 
         LogManager.info("Java Path: " + settings.javaPath);
 
-        LogManager.info("64 Bit Java: " + OS.is64Bit());
+        LogManager.info("64 Bit Java: " + Java.is64Bit());
 
         int maxRam = OS.getMaximumRam();
         LogManager.info("RAM Available: " + (maxRam == 0 ? "Unknown" : maxRam + "MB"));

src/main/java/com/atlauncher/Launcher.java

@@ -141,7 +141,7 @@ public class Launcher {
 
         PackManager.removeUnusedImages(); // remove unused pack images
 
-        if (OS.isWindows() && !OS.is64Bit() && OS.isWindows64Bit()) {
+        if (OS.isWindows() && !Java.is64Bit() && OS.is64Bit()) {
             LogManager.warn("You're using 32 bit Java on a 64 bit Windows install!");
 
             int ret = DialogManager.yesNoDialog().setTitle(GetText.tr("Running 32 Bit Java on 64 Bit Windows"))

src/main/java/com/atlauncher/gui/dialogs/instancesettings/JavaInstanceSettingsTab.java

@@ -105,7 +105,7 @@ public class JavaInstanceSettingsTab extends JPanel {
 
         JPanel initialMemoryPanel = new JPanel();
         initialMemoryPanel.setLayout(new FlowLayout(FlowLayout.RIGHT, 0, 0));
-        if (!OS.is64Bit()) {
+        if (!Java.is64Bit()) {
             initialMemoryPanel.add(initialMemoryLabelWarning);
         }
         initialMemoryPanel.add(initialMemoryLabel);

src/main/java/com/atlauncher/gui/tabs/settings/JavaSettingsTab.java

@@ -110,7 +110,7 @@ public class JavaSettingsTab extends AbstractSettingsTab implements Relocalizati
 
         JPanel initialMemoryPanel = new JPanel();
         initialMemoryPanel.setLayout(new FlowLayout(FlowLayout.RIGHT, 0, 0));
-        if (!OS.is64Bit()) {
+        if (!Java.is64Bit()) {
             initialMemoryPanel.add(initialMemoryLabelWarning);
         }
         initialMemoryPanel.add(initialMemoryLabel);
@@ -141,7 +141,7 @@ public class JavaSettingsTab extends AbstractSettingsTab implements Relocalizati
 
         JPanel maximumMemoryPanel = new JPanel();
         maximumMemoryPanel.setLayout(new FlowLayout(FlowLayout.RIGHT, 0, 0));
-        if (!OS.is64Bit()) {
+        if (!Java.is64Bit()) {
             maximumMemoryPanel.add(new JLabelWithHover(WARNING_ICON, new HTMLBuilder().center().split(100).text(GetText
                     .tr("You're running a 32 bit Java and therefore cannot use more than 1GB of Ram. Please see http://atl.pw/32bit for help."))
                     .build(), RESTART_BORDER));

src/main/java/com/atlauncher/utils/Java.java

@@ -46,6 +46,13 @@ public class Java {
         return System.getProperty("java.version");
     }
 
+    /**
+     * Checks if the Java being used is 64 bit.
+     */
+    public static boolean is64Bit() {
+        return System.getProperty("sun.arch.data.model").contains("64");
+    }
+
     /**
      * Get the Java version used to run Minecraft.
      *

src/main/java/com/atlauncher/utils/OS.java

@@ -59,6 +59,7 @@ import com.atlauncher.utils.javafinder.JavaInfo;
 import oshi.SystemInfo;
 import oshi.hardware.GlobalMemory;
 import oshi.hardware.HardwareAbstractionLayer;
+import oshi.software.os.OperatingSystem;
 
 public enum OS {
     LINUX, WINDOWS, OSX;
@@ -277,17 +278,19 @@ public enum OS {
     }
 
     /**
-     * Checks if the Java being used is 64 bit.
+     * Checks if the OS is 64 bit.
      */
     public static boolean is64Bit() {
-        return System.getProperty("sun.arch.data.model").contains("64");
-    }
+        try {
+            SystemInfo systemInfo = OS.getSystemInfo();
+            OperatingSystem os = systemInfo.getOperatingSystem();
 
-    /**
-     * Checks if Windows is 64 bit.
-     */
-    public static boolean isWindows64Bit() {
-        return System.getenv("ProgramFiles(x86)") != null;
+            return os.getBitness() == 64;
+        } catch (Throwable ignored) {
+        }
+
+        // worse case fallback to checking the Java install
+        return Java.is64Bit();
     }
 
     /**