Bug 264378

Description Francois Fernandes 2009-02-10 11:27:03 EST

Sometimes my eclipse (and the eclipse of other colleages) is going wild and loosing it's association to a particular JRE/JDK. That means that for some reason, eclipse tries to recompile the projects and fails because it can't resolve classes like java.lang.Object.

When looking at the JRE System Library entry using the Package Explorer, it is impossible to expand the Entries like rt.jar, jce.jar, etc. When selecting one of those jars the following error is logged:
Java Model Exception: Java Model Status [C:\Program Files (x86)\Java\jdk1.5.0_16\jre\lib\rt.jar is not on its project's build path]
	at org.eclipse.jdt.internal.core.PackageFragmentRoot.getRawClasspathEntry(PackageFragmentRoot.java:553)
	at org.eclipse.jdt.internal.ui.actions.JarImportWizardAction.selectionChanged(JarImportWizardAction.java:89)
	at org.eclipse.jdt.internal.ui.actions.JarImportWizardAction.selectionChanged(JarImportWizardAction.java:107)
	at org.eclipse.jface.viewers.Viewer$2.run(Viewer.java:162)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:37)
	at org.eclipse.core.runtime.Platform.run(Platform.java:880)
	at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:48)
	at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
	at org.eclipse.jface.viewers.Viewer.fireSelectionChanged(Viewer.java:160)
	at org.eclipse.jface.viewers.StructuredViewer.updateSelection(StructuredViewer.java:2062)
	at org.eclipse.jface.viewers.StructuredViewer.handleSelect(StructuredViewer.java:1138)
	at org.eclipse.jface.viewers.StructuredViewer$4.widgetSelected(StructuredViewer.java:1168)
	at org.eclipse.jface.util.OpenStrategy.fireSelectionEvent(OpenStrategy.java:227)
	at org.eclipse.jface.util.OpenStrategy.access$3(OpenStrategy.java:221)
	at org.eclipse.jface.util.OpenStrategy$1.handleEvent(OpenStrategy.java:388)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3823)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3422)
	at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2382)
	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2346)
	at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2198)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:493)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:488)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:193)
	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:386)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1236)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1212)


To get rid of this is difficult. Sometimes it is enough to clean all projects, refresh all and then rebuild them. Sometimes (as it is this time) it is enough to wait for a moment and retry to expand the e.g. rt.jar node. Most often I have to restart eclipse, do some clean-refresh-build sequences and then it will work just fine.