Bug 28698 Ctrl+O (show outline) does not work if the file being shown in the editor is read only
M4 The summary tells all. Works if the file is not read only. Is this by design?
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
}
		
		/*
		 * @see org.eclipse.jdt.internal.ui.text.link.LinkedPositionUI.ExitListener#exit(boolean)
		 */
		public void exit(boolean accept) {
			if (accept)
				return;
			
			try {
				final ISourceViewer sourceViewer= getSourceViewer();
				IDocument document= sourceViewer.getDocument();
				document.replace(fOffset, fLength, null);
			} catch (BadLocationException e) {
			}
		}
	}
	
	protected AnnotationType getAnnotationType(String preferenceKey) {
		Iterator e= ANNOTATION_MAP.keySet().iterator();
		while (e.hasNext()) {
			AnnotationType type= (AnnotationType) e.next();
			AnnotationInfo info= (AnnotationInfo) ANNOTATION_MAP.get(type);
			if (info != null) {
				if (preferenceKey.equals(info.fColorPreference) || preferenceKey.equals(info.fEditorPreference) || preferenceKey.equals(info.fOverviewRulerPreference)) 
					return type;
			}
		}
		return null;
	}