Bug 29711 Move refactoring doesn't honor read-only flags
Build I20030115 - JUnit setup - create TestCase.java in junit.runner - make it read-only - move TestCase from framework to runner - answer yes to override observe: the file in runner gets replaced althouh it is read-only
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/SelectionTransferDropAdapter.java
}
	
	private static ICompilationUnit getCompilationUnit(Object target){
		if (target instanceof ISourceReference)
			return SourceReferenceUtil.getCompilationUnit((ISourceReference)target);
		else
			return null;	
	}
	
	private boolean canPasteSourceReferences(Object target) throws JavaModelException{
		ISourceReference[] elements= getDragableSourceReferences();
		if (elements.length != fElements.size())
			return false;
		SelectionDispatchAction pasteAction= ReorgActionFactory.createPasteAction(elements, target);
		pasteAction.update(pasteAction.getSelection());
		return pasteAction.isEnabled();
	}
	
	private ISourceReference[] getDragableSourceReferences(){
		List result= new ArrayList(fElements.size());
		for(Iterator iter= fElements.iterator(); iter.hasNext();){
			Object each= iter.next();
			if (isDragableSourceReferences(each))
				result.add(each);
		}
		return (ISourceReference[])result.toArray(new ISourceReference[result.size()]);
	}
	
	private static boolean isDragableSourceReferences(Object element) {
		if (!(element instanceof ISourceReference))