Bug 48852 Found the followng exception in the log
I20031216 java.lang.IllegalArgumentException: at org.eclipse.core.internal.runtime.Assert.isLegal(Assert.java:56) at org.eclipse.core.internal.runtime.Assert.isLegal(Assert.java:41) at org.eclipse.core.runtime.Status.setMessage(Status.java:156) at org.eclipse.core.runtime.Status.<init>(Status.java:75) at org.eclipse.ui.editors.text.TextFileDocumentProvider.executeOperation (TextFileDocumentProvider.java:396) at org.eclipse.ui.editors.text.TextFileDocumentProvider.validateState (TextFileDocumentProvider.java:812) at org.eclipse.ui.texteditor.AbstractTextEditor.validateState (AbstractTextEditor.java:3035) at org.eclipse.ui.texteditor.AbstractTextEditor$16.run (AbstractTextEditor.java:3080) at org.eclipse.swt.custom.BusyIndicator.showWhile (BusyIndicator.java:84) at org.eclipse.ui.texteditor.AbstractTextEditor.validateEditorInputState (AbstractTextEditor.java:3075) at org.eclipse.ui.texteditor.AbstractTextEditor$ElementStateListener$Validator.ver ifyText(AbstractTextEditor.java:212) at org.eclipse.swt.widgets.TypedListener.handleEvent (TypedListener.java:193) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:82) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:847) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:871) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:856) at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:664) at org.eclipse.swt.custom.StyledText.modifyContent (StyledText.java:5947) at org.eclipse.swt.custom.StyledText.sendKeyEvent(StyledText.java:6931) at org.eclipse.swt.custom.StyledText.doContent(StyledText.java:2554) at org.eclipse.swt.custom.StyledText.handleKey(StyledText.java:5300) at org.eclipse.swt.custom.StyledText.handleKeyDown (StyledText.java:5323) at org.eclipse.swt.custom.StyledText$8.handleEvent (StyledText.java:5070) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:82) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:847) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:871) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:856) at org.eclipse.swt.widgets.Control.sendKeyEvent(Control.java:1716) at org.eclipse.swt.widgets.Control.sendKeyEvent(Control.java:1712) at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:3036) at org.eclipse.swt.widgets.Control.windowProc(Control.java:2939) at org.eclipse.swt.widgets.Display.windowProc(Display.java:2836) at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method) at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:1369) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:1990) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1506) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1482) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench (Workbench.java:246) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:139) at org.eclipse.ui.internal.ide.IDEApplication.run (IDEApplication.java:47) at org.eclipse.core.internal.runtime.PlatformActivator$1.run (PlatformActivator.java:233) at org.eclipse.core.runtime.adaptor.EclipseStarter.run (EclipseStarter.java:84) 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:324) at org.eclipse.core.launcher.Main.basicRun(Main.java:280) at org.eclipse.core.launcher.Main.run(Main.java:741) at org.eclipse.core.launcher.Main.main(Main.java:582)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitDocumentProvider.java
List list= (List) value;
					for (Iterator e = list.iterator(); e.hasNext();)
						setOverlay(e.next(), problemAnnotation);
				} else {
					setOverlay(value, problemAnnotation);
				}
			}
			
			/**
			 * Tells this annotation model to collect temporary problems from now on.
			 */
			private void startCollectingProblems() {
				fCollectedProblems= new ArrayList();
				fGeneratedAnnotations= new ArrayList();  
			}
			
			/**
			 * Tells this annotation model to no longer collect temporary problems.
			 */
			private void stopCollectingProblems() {
				if (fGeneratedAnnotations != null) {
					removeAnnotations(fGeneratedAnnotations, true, true);
					fGeneratedAnnotations.clear();
				}
				fCollectedProblems= null;
				fGeneratedAnnotations= null;
			}
			
			/*
			 * @see org.eclipse.jface.text.source.AnnotationModel#fireModelChanged(org.eclipse.jface.text.source.AnnotationModelEvent)