import org.apache.hadoop.hdfs.server.namenode.AclFeature; //导入依赖的package包/类
Root(INodeDirectory other) {
  // Always preserve ACL, XAttr.
  super(other, false, Lists.newArrayList(
    Iterables.filter(Arrays.asList(other.getFeatures()), new Predicate<Feature>() {

      @Override
      public boolean apply(Feature input) {
        if (AclFeature.class.isInstance(input) 
            || XAttrFeature.class.isInstance(input)) {
          return true;
        }
        return false;
      }
      
    }))
    .toArray(new Feature[0]));
}
 

import org.apache.hadoop.hdfs.server.namenode.AclFeature; //导入依赖的package包/类
private void deleteSnapshotWithAclAndVerify(AclFeature aclFeature,
    Path pathToCheckAcl, int totalAclFeatures) throws IOException {
  hdfs.deleteSnapshot(path, snapshotName);
  AclFeature afterDeleteAclFeature = FSAclBaseTest.getAclFeature(
      pathToCheckAcl, cluster);
  assertSame(aclFeature, afterDeleteAclFeature);
  assertEquals("Reference count should remain same"
      + " even after deletion of snapshot", 1,
      afterDeleteAclFeature.getRefCount());

  hdfs.removeAcl(pathToCheckAcl);
  assertEquals("Reference count should be 0", 0, aclFeature.getRefCount());
  assertEquals("Unique ACL features should remain same", totalAclFeatures,
      AclStorage.getUniqueAclFeatures().getUniqueElementsSize());
}
 

import org.apache.hadoop.hdfs.server.namenode.AclFeature; //导入依赖的package包/类
private void checkAndRemoveHdfsAcl(INodeAuthorizationInfo node,
    boolean warn) {
  AclFeature f = defaultAuthzProvider.getAclFeature(node,
      Snapshot.CURRENT_STATE_ID);
  if (f != null) {
    defaultAuthzProvider.removeAclFeature(node);
  } else {
    if (warn) {
      LOG.warn("### removeAclFeature is requested on {}, but it does not " +
          "have any acl.", node);
    }
  }
}
 

import org.apache.hadoop.hdfs.server.namenode.AclFeature; //导入依赖的package包/类
@Override
public void addAclFeature(INodeAuthorizationInfo node, AclFeature f) {
  // always fall through to defaultAuthZProvider, 
  // issue warning when the path is sentry managed
  if (isSentryManaged(node)) {
    LOG.warn("### addAclFeature {} (sentry managed path) {}, update HDFS." +
        WARN_VISIBILITY,
        node.getFullPathName(), f.toString());
    // For Sentry-managed path, remove ACL silently before adding new ACL
    checkAndRemoveHdfsAcl(node, false);
  }
  defaultAuthzProvider.addAclFeature(node, f);
}
 

import org.apache.hadoop.hdfs.server.namenode.AclFeature; //导入依赖的package包/类
@Override
public void addAclFeature(AclFeature f) {
  throw new UnsupportedOperationException("ACLs are not supported on symlinks");
}
 

import org.apache.hadoop.hdfs.server.namenode.AclFeature; //导入依赖的package包/类
Root(INodeDirectory other) {
  // Always preserve ACL.
  super(other, false, Lists.newArrayList(
    Iterables.filter(Arrays.asList(other.getFeatures()), AclFeature.class))
    .toArray(new Feature[0]));
}
 

import org.apache.hadoop.hdfs.server.namenode.AclFeature; //导入依赖的package包/类
@Override
public AclFeature getAclFeature(INodeAuthorizationInfo node, int snapshotId) {
  AclFeature f = null;
  String[] pathElements = getPathElements(node);
  String p = Arrays.toString(pathElements);
  boolean isPrefixed = false;
  boolean isStale = false;
  boolean hasAuthzObj = false;
  Map<String, AclEntry> aclMap = null;
  if (!authzInfo.isUnderPrefix(pathElements)) {
    isPrefixed = false;
    f = defaultAuthzProvider.getAclFeature(node, snapshotId);
  } else if (!authzInfo.doesBelongToAuthzObject(pathElements)) {
    isPrefixed = true;
    f = defaultAuthzProvider.getAclFeature(node, snapshotId);
  } else {
    isPrefixed = true;
    hasAuthzObj = true;
    aclMap = new HashMap<String, AclEntry>();
    if (originalAuthzAsAcl) {
      String user = defaultAuthzProvider.getUser(node, snapshotId);
      String group = getDefaultProviderGroup(node, snapshotId);
      FsPermission perm = defaultAuthzProvider.getFsPermission(node, snapshotId);
      addToACLMap(aclMap, createAclEntries(user, group, perm));
    } else {
      addToACLMap(aclMap,
          createAclEntries(this.user, this.group, this.permission));
    }
    if (!authzInfo.isStale()) {
      isStale = false;
      addToACLMap(aclMap, authzInfo.getAclEntries(pathElements));
      f = new SentryAclFeature(ImmutableList.copyOf(aclMap.values()));
    } else {
      isStale = true;
      f = new SentryAclFeature(ImmutableList.copyOf(aclMap.values()));
    }
  }
  if (LOG.isDebugEnabled()) {
    LOG.debug("### getAclEntry \n[" + p + "] : ["
        + "isPreifxed=" + isPrefixed
        + ", isStale=" + isStale
        + ", hasAuthzObj=" + hasAuthzObj
        + ", origAuthzAsAcl=" + originalAuthzAsAcl + "]\n"
        + "[" + (aclMap == null ? "null" : aclMap) + "]\n"
        + "[" + (f == null ? "null" : f.getEntries()) + "]\n");
  }
  return f;
}