private static boolean isValidCandidate(PsiFile file, PsiMember candidate){
    if (!candidate.isValid()) return false;
    if (PsiUtil.isMemberAccessibleAt(candidate, file)) return true;
    VirtualFile virtualFile = PsiUtilCore.getVirtualFile(candidate);
    if (virtualFile == null) return false;
    return ProjectFileIndex.getInstance(file.getProject()).isInContent(virtualFile);
  }
private static boolean isValidCandidate(PsiFile file, PsiMember candidate)