1   /*
2    * Copyright (C) 2007 The Guava Authors
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    * http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  package com.google.common.collect;
18  
19  import com.google.common.annotations.GwtCompatible;
20  
21  import java.util.Iterator;
22  
23  /**
24   * An iterator which forwards all its method calls to another iterator.
25   * Subclasses should override one or more methods to modify the behavior of the
26   * backing iterator as desired per the <a
27   * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
28   *
29   * @author Kevin Bourrillion
30   * @since 2.0 (imported from Google Collections Library)
31   */
32  @GwtCompatible
33  public abstract class ForwardingIterator<T>
34      extends ForwardingObject implements Iterator<T> {
35  
36    /** Constructor for use by subclasses. */
37    protected ForwardingIterator() {}
38  
39    @Override protected abstract Iterator<T> delegate();
40  
41    @Override
42    public boolean hasNext() {
43      return delegate().hasNext();
44    }
45  
46    @Override
47    public T next() {
48      return delegate().next();
49    }
50  
51    @Override
52    public void remove() {
53      delegate().remove();
54    }
55  }