Bug 20040 java editor: undo does not work correctly
20020612 .create new class .'override methods...' - add clone() .undo .redo .undo the plain text editor does not exhibit this mis-behavior you're left with garbage like (pressing undo/redo more times produces even more garbage): public class Dfg { r.clone(); //<<GARBAGE } //<<GARBAGE }
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
Preferences preferences= JavaCore.getPlugin().getPluginPreferences();
		return preferences.getInt(CODE_FORMATTER_TAB_SIZE);	
	}
	
	private void startTabConversion() {
		if (fTabConverter == null) {
			fTabConverter= new TabConverter();
			configureTabConverter();
			fTabConverter.setNumberOfSpacesPerTab(getTabSize());
			AdaptedSourceViewer asv= (AdaptedSourceViewer) getSourceViewer();
			asv.addTextConverter(fTabConverter);
			
			asv.updateIndentationPrefixes();
		}
	}
	
	private void stopTabConversion() {
		if (fTabConverter != null) {
			AdaptedSourceViewer asv= (AdaptedSourceViewer) getSourceViewer();
			asv.removeTextConverter(fTabConverter);
			
			asv.updateIndentationPrefixes();
			fTabConverter= null;
		}
	}
	
	private boolean isTabConversionEnabled() {
		IPreferenceStore store= getPreferenceStore();
		return store.getBoolean(SPACES_FOR_TABS);
	}