如何使用SWT / Eclipse在Mac OS X中执行jar？

Question

I changed the Java to 32 bit mode, to allow the SWT run, when I debug, it works well. But when I use Eclipse to export .jar, it shows this error.

I already added chmod 777. What did I do wrong?

Here is the console result:

20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]    Exception in thread "main" 
20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]    java.lang.UnsatisfiedLinkError: Cannot load 32-bit SWT libraries on 64-bit JVM
20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]        at org.eclipse.swt.internal.Library.loadLibrary(Unknown Source)
20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]        at org.eclipse.swt.internal.Library.loadLibrary(Unknown Source)
20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]        at org.eclipse.swt.internal.C.<clinit>(Unknown Source)
20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]        at org.eclipse.swt.widgets.Display.<clinit>(Unknown Source)
20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]        at com.testing.SWTApp.main(SWTApp.java:54)

The MANIFEST is like follow:

Manifest-Version: 1.0
Class-Path: .
Main-Class: com.testing.SWTApp 

Answer 1

Try this:

java -d32 -XstartOnFirstThread -jar myapp.jar

The -d32 option will cause the VM to run in 32-bit mode. The -XstartOnFirstThread option is necessary for SWT applications.

Answer 2

the swt jar executes native librairies which depend on your OS.
You have one version of swt for: macosx 32 & 64 bits
winsows 32 & 64 bits
linux 32 & 64 bits

you can specify the -d32 jvm option. It will force the JVM to run in the 32 bits mode. However, you need to have a 32 bits implementation of the JVM available in your OS.

You could also load dynamically at runtime the right SWT Jar: you include in your app both jar (swt-macosx-32bits & swt-macosx-64bits) and load programatically the required jar:

String osArch = System.getProperty ("sun.arch.data.model");
if (osArch == null) {
    osArch = System.getProperty ("com.ibm.vm.bitmode");
}
URLClassLoader classLoader = (URLClassLoader) JarLoaderUtils.class.getClassLoader();
URL.setURLStreamHandlerFactory(new RsrcURLStreamHandlerFactory(classLoader));
Method addUrlMethod = URLClassLoader.class.getDeclaredMethod("addURL", URL.class);
addUrlMethod.setAccessible(true);
swtFileName = osArch.contains("64") ? SWT_MAC_x86_64 : SWT_MAC_x86;
URL swtFileUrl = new URL("rsrc:" + swtFileName);
addUrlMethod.invoke(classLoader, swtFileUrl);

Note that you seem to run your app in macosx, you should also add the -XstartOnFirstThread option.

Answer 3

The problem is it's not Eclipse that is executing your built jar, it's Finder / the java launcher. What you need to do is goto /Applications/Utilities/Java Preferences.app and reorder (click drag) so that your 32 bit version is chosen before the 64 bit version. For reference mine looks like this:

then when you execute java -version (no -d parameter) you'll get the 32 bit JRE chosen. and when you double click the jar in finder or use open app.jar it should work.

Answer 4

20/11/2011 12:10:36 AM  [0x0-0x3d89d86].com.apple.JarLauncher[73111]    java.lang.UnsatisfiedLinkError: Cannot load 32-bit SWT libraries on 64-bit JVM

Please focus on this error. You need 64-bit dependency libraries for launching it. It depends on default java loaded. If its 32-bit package, you need your default jvm classpath to be 32-bit java. You have option for changing it in eclipse.