Bug 46805 prepare Compare for encoding support
I20031111 The Compare plugin only supports the global workspace encoding. It does not support encodings per file.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/compare/JavaCompareAction.java
String left= null;
		String right= null;
		
		try {
			left= getExtendedSource(fLeft);
		} catch (JavaModelException ex) {
			JavaPlugin.log(ex);
		}
		
		try {
			right= getExtendedSource(fRight);
		} catch (JavaModelException ex) {
			JavaPlugin.log(ex);
		}
		
		fJavaElementLabelProvider= new JavaElementLabelProvider(
					JavaElementLabelProvider.SHOW_PARAMETERS |
					JavaElementLabelProvider.SHOW_OVERLAY_ICONS |
					JavaElementLabelProvider.SHOW_ROOT);
		
		if (left == null || right == null) {
			String errorTitle= JavaCompareUtilities.getString(bundle, "errorTitle"); 
			String errorFormat= JavaCompareUtilities.getString(bundle, "errorFormat"); 
		
			Object element= null;
			if (left == null)
				element= fLeft;
			else
				element= fRight;