String (PsiClassHolderFileStub<?> stub) { String packageName = null; if (stub instanceof PsiJavaFileStub) { packageName = ((PsiJavaFileStub)stub).getPackageName(); } else { PsiClass[] psiClasses = stub.getClasses(); if (psiClasses.length > 0) { String className = psiClasses[0].getQualifiedName(); if (className != null) { int index = className.lastIndexOf('.'); if (index >= 0) { packageName = className.substring(0, index); } } } } return !StringUtil.isEmpty(packageName) ? packageName : null; }