return null;
return new IJavaElement[0];
	private IJavaElement[] getSelectedElements(IStructuredSelection selection) {		List elements= selection.toList();		int size= elements.size();		if (size == 0)			return null;					ArrayList result= new ArrayList(size);					for (int i= 0; i < size; i++) {			Object e= elements.get(i);			if (e instanceof ICompilationUnit) {				ICompilationUnit unit= (ICompilationUnit) e;				IType[] types= new IType[0];				try {					types= unit.getTypes();				} catch (JavaModelException ex) {				}				for (int j= 0; j < types.length; j++) {					result.add(types[j]);				} 			}			else if (e instanceof IMethod || e instanceof IType || e instanceof IField) {				result.add(e);			} else {				return null;			}		}		return (IJavaElement[])result.toArray(new IJavaElement[result.size()]);	}