How to use

check

method

in

org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker

/** Guarded by {@link FSNamesystem#readLock()}
 * @throws AccessControlException
 * @throws ParentNotDirectoryException
 * @throws UnresolvedPathException
 */
private void checkTraverse(INodeAttributes[] inodeAttrs, INode[] inodes,
  byte[][] components, int last) throws AccessControlException,
    UnresolvedPathException, ParentNotDirectoryException {
 for (int i=0; i <= last; i++) {
  checkIsDirectory(inodes[i], components, i);
  check(inodeAttrs, components, i, FsAction.EXECUTE);
 }
}

check(inodeAttrs, components, ancestorIndex, ancestorAccess);
check(inodeAttrs, components, inodeAttrs.length - 2, parentAccess);
check(inodeAttrs, components, inodeAttrs.length - 1, access);

private void check(INode[] inodes, int i, FsAction access
  ) throws AccessControlException {
 check(i >= 0? inodes[i]: null, access);
}

check(inodeAttrs, ancestorIndex, ancestorAccess);
check(inodeAttrs, inodeAttrs.length - 2, parentAccess);
check(inodeAttrs, inodeAttrs.length - 1, access);

private void checkTraverse(INode[] inodes, int last
  ) throws AccessControlException {
 for(int j = 0; j <= last; j++) {
  check(inodes[j], FsAction.EXECUTE);
 }
}

check(inodeAttrs, ancestorIndex, ancestorAccess);
check(inodeAttrs, inodeAttrs.length - 2, parentAccess);
check(inodeAttrs, inodeAttrs.length - 1, access);

private void checkSubAccess(INode inode, FsAction access
  ) throws AccessControlException {
 if (inode == null || !inode.isDirectory()) {
  return;
 }
 Stack<INodeDirectory> directories = new Stack<INodeDirectory>();
 for(directories.push((INodeDirectory)inode); !directories.isEmpty(); ) {
  INodeDirectory d = directories.pop();
  check(d, access);
  for(INode child : d.getChildren()) {
   if (child.isDirectory()) {
    directories.push((INodeDirectory)child);
   }
  }
 }
}

check(inodes, ancestorIndex, ancestorAccess);
check(inodes, inodes.length - 2, parentAccess);
check(inodes[inodes.length - 1], access);