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1   /*
2    * Copyright 2003,2004 The Apache Software Foundation.
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  
18   */
19  
20  package org.apache.pluto.util;
21  
22  import java.util.Collection;
23  import java.util.Enumeration;
24  import java.util.Iterator;
25  import java.util.Map;
26  import java.util.NoSuchElementException;
27  
28  
29  /***
30   * Uitlity class to wraps an <code>Enumeration</code> around a
31   * Collection, i.e. <code>Iterator</code> classes.
32   */
33  
34  public final class Enumerator implements Enumeration
35  {
36  
37  
38      // Iterator over which the Enumeration takes place
39      private Iterator iterator = null;
40  
41  
42      /***
43       * Returns an Enumeration over the specified Collection.
44       *
45       * @param collection Collection with values that should be enumerated
46       */
47      public Enumerator(Collection collection)
48      {
49          this(collection.iterator());
50      }
51  
52  
53      /***
54       * Returns an Enumeration over the values of the
55       * specified Iterator.
56       *
57       * @param iterator Iterator to be wrapped
58       */
59      public Enumerator(Iterator iterator)
60      {
61          super();
62          this.iterator = iterator;
63      }
64  
65  
66      /***
67       * Returns an Enumeration over the values of the specified Map.
68       *
69       * @param map Map with values that should be enumerated
70       */
71      public Enumerator(Map map)
72      {
73          this(map.values().iterator());
74      }
75  
76  
77  
78      /***
79       * Tests if this enumeration contains more elements.
80       *
81       * @return <code>true</code> if this enumeration contains at 
82       *          least one more element to provide,
83       *          <code>false</code> otherwise.
84       */
85      public boolean hasMoreElements()
86      {
87          return(iterator.hasNext());
88      }
89  
90  
91      /***
92       * Returns the next element of this enumeration.
93       *
94       * @return the next element of this enumeration
95       *
96       * @exception NoSuchElementException if no more elements exist
97       */
98      public Object nextElement() throws NoSuchElementException {
99          return(iterator.next());
100     }
101 
102 
103 }