| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.hadoop.fs.permission; |
| |
| import java.util.Collections; |
| import java.util.List; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.fs.permission.AclEntry; |
| import org.apache.hadoop.fs.permission.AclEntryScope; |
| |
| /** |
| * Groups a list of ACL entries into separate lists for access entries vs. |
| * default entries. |
| */ |
| @InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"}) |
| @InterfaceStability.Unstable |
| public final class ScopedAclEntries { |
| private static final int PIVOT_NOT_FOUND = -1; |
| |
| private final List<AclEntry> accessEntries; |
| private final List<AclEntry> defaultEntries; |
| |
| /** |
| * Creates a new ScopedAclEntries from the given list. It is assumed that the |
| * list is already sorted such that all access entries precede all default |
| * entries. |
| * |
| * @param aclEntries List<AclEntry> to separate |
| */ |
| public ScopedAclEntries(List<AclEntry> aclEntries) { |
| int pivot = calculatePivotOnDefaultEntries(aclEntries); |
| if (pivot != PIVOT_NOT_FOUND) { |
| accessEntries = pivot != 0 ? aclEntries.subList(0, pivot) : |
| Collections.<AclEntry>emptyList(); |
| defaultEntries = aclEntries.subList(pivot, aclEntries.size()); |
| } else { |
| accessEntries = aclEntries; |
| defaultEntries = Collections.emptyList(); |
| } |
| } |
| |
| /** |
| * Returns access entries. |
| * |
| * @return List<AclEntry> containing just access entries, or an empty list if |
| * there are no access entries |
| */ |
| public List<AclEntry> getAccessEntries() { |
| return accessEntries; |
| } |
| |
| /** |
| * Returns default entries. |
| * |
| * @return List<AclEntry> containing just default entries, or an empty list if |
| * there are no default entries |
| */ |
| public List<AclEntry> getDefaultEntries() { |
| return defaultEntries; |
| } |
| |
| /** |
| * Returns the pivot point in the list between the access entries and the |
| * default entries. This is the index of the first element in the list that is |
| * a default entry. |
| * |
| * @param aclBuilder ArrayList<AclEntry> containing entries to build |
| * @return int pivot point, or -1 if list contains no default entries |
| */ |
| private static int calculatePivotOnDefaultEntries(List<AclEntry> aclBuilder) { |
| for (int i = 0; i < aclBuilder.size(); ++i) { |
| if (aclBuilder.get(i).getScope() == AclEntryScope.DEFAULT) { |
| return i; |
| } |
| } |
| return PIVOT_NOT_FOUND; |
| } |
| } |