jalopy source code formatter give Unhandled event loop exception when formatting - eclipse-juno

Question

I have used eclipse Indigo and Juno to set up jalopy according to the jalopy installation guide.My Jalopy version is 1.9.4. I can format the code in Indigo without any problem. But I can't format the code
in Juno. In error log view, I can see Unhandled event loop exception in org.eclipse.ui plugin, when I try to format the code in Juno.
this is the relevant exception stack trace
org.eclipse.swt.SWTException: Failed to execute runnable (java.util.ConcurrentModificationException)
at org.eclipse.swt.SWT.error(SWT.java:4361)
at org.eclipse.swt.SWT.error(SWT.java:4276)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:138)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4144)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3761)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1022)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:916)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:86)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:585)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:540)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:124)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
at org.eclipse.equinox.launcher.Main.main(Main.java:1414)
Caused by: java.util.ConcurrentModificationException
at com.triemax.EclipsePlugin.l(EclipsePlugin.java)
at com.triemax.EclipsePlugin.a(EclipsePlugin.java:74)
at com.triemax.nu.run(nu.java:8)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:135)
... 24 more
what is the reason for this exception? how to prevent this?
EDIT :same exception arise in Eclipse Kepler

Answer 1

The version you have is not compatible with Juno or Kepler. A more recent build fixes the problem.