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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      https://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.collections4.bag;
18  
19  import java.util.Comparator;
20  
21  import org.apache.commons.collections4.Bag;
22  import org.apache.commons.collections4.SortedBag;
23  import org.apache.commons.collections4.multiset.SynchronizedSortedMultiSet;
24  
25  /**
26   * Decorates another {@link SortedBag} to synchronize its behavior
27   * for a multithreaded environment.
28   * <p>
29   * Methods are synchronized, then forwarded to the decorated bag.
30   * Iterators must be separately synchronized around the loop.
31   * </p>
32   * <p>
33   * This class is Serializable from Commons Collections 3.1.
34   * </p>
35   *
36   * @param <E> The type of elements in this bag
37   * @since 3.0
38   * @deprecated Since 4.6.0, use {@link SynchronizedSortedMultiSet} instead.
39   */
40  @Deprecated
41  public class SynchronizedSortedBag<E> extends SynchronizedBag<E> implements SortedBag<E> {
42  
43      /** Serialization version */
44      private static final long serialVersionUID = 722374056718497858L;
45  
46      /**
47       * Factory method to create a synchronized sorted bag.
48       *
49       * @param <E> The type of the elements in the bag
50       * @param bag  The bag to decorate, must not be null
51       * @return A new synchronized SortedBag
52       * @throws NullPointerException if bag is null
53       * @since 4.0
54       */
55      public static <E> SynchronizedSortedBag<E> synchronizedSortedBag(final SortedBag<E> bag) {
56          return new SynchronizedSortedBag<>(bag);
57      }
58  
59      /**
60       * Constructor that wraps (not copies).
61       *
62       * @param bag  The bag to decorate, must not be null
63       * @param lock  The lock to use, must not be null
64       * @throws NullPointerException if bag or lock is null
65       */
66      protected SynchronizedSortedBag(final Bag<E> bag, final Object lock) {
67          super(bag, lock);
68      }
69  
70      /**
71       * Constructor that wraps (not copies).
72       *
73       * @param bag  The bag to decorate, must not be null
74       * @throws NullPointerException if bag is null
75       */
76      protected SynchronizedSortedBag(final SortedBag<E> bag) {
77          super(bag);
78      }
79  
80      @Override
81      public synchronized Comparator<? super E> comparator() {
82          synchronized (lock) {
83              return getSortedBag().comparator();
84          }
85      }
86  
87      @Override
88      public synchronized E first() {
89          synchronized (lock) {
90              return getSortedBag().first();
91          }
92      }
93  
94      /**
95       * Gets the bag being decorated.
96       *
97       * @return The decorated bag
98       */
99      protected SortedBag<E> getSortedBag() {
100         return (SortedBag<E>) decorated();
101     }
102 
103     @Override
104     public synchronized E last() {
105         synchronized (lock) {
106             return getSortedBag().last();
107         }
108     }
109 
110 }