Bug 13056 can't delete 2 identical methods
class Ad { void f(){}; void f(){}; } you can't delete the 2 f methods (together) it works if you delete them separately
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/reorg/SourceReferenceAction.java
protected abstract void perform() throws CoreException;
	
	/*
	 * @see RefactoringAction#canOperateOn(IStructuredSelection)
	 */
	public boolean canOperateOn(IStructuredSelection selection) {
		try{
			if (selection.isEmpty())			
				return false;
			Object[] elems= selection.toArray();
			for (int i= 0; i < elems.length; i++) {
				Object elem= elems[i];
				if (! canWorkOn(elem))
					return false;
			}
			return true;
		} catch (JavaModelException e){
			JavaPlugin.log(e);
			return false;
		}	
	}
	
	private ISourceReference[] getSelectedElements(){
		return getWorkingCopyElements(getStructuredSelection().toList());
	}
	
	private static boolean canWorkOn(Object elem) throws JavaModelException{
		if (elem == null)
			return false;