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1   /*
2    * Copyright (c) 2003, Henri Yandell
3    * All rights reserved.
4    * 
5    * Redistribution and use in source and binary forms, with or 
6    * without modification, are permitted provided that the 
7    * following conditions are met:
8    * 
9    * + Redistributions of source code must retain the above copyright notice, 
10   *   this list of conditions and the following disclaimer.
11   * 
12   * + Redistributions in binary form must reproduce the above copyright notice, 
13   *   this list of conditions and the following disclaimer in the documentation 
14   *   and/or other materials provided with the distribution.
15   * 
16   * + Neither the name of Genjava-Core nor the names of its contributors 
17   *   may be used to endorse or promote products derived from this software 
18   *   without specific prior written permission.
19   * 
20   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
21   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
22   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
23   * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
24   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
25   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
26   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
27   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
28   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
29   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
30   * POSSIBILITY OF SUCH DAMAGE.
31   */
32  package com.generationjava.collections;
33  
34  import java.util.ArrayList;
35  import java.util.Collection;
36  import java.util.List;
37  
38  /***
39   * Only allows N elements in. Once size N is reached, all 
40   * new adds are ignored and inserts mean the one on the end 
41   * of the list is removed.
42   */
43  public class LimitedList extends ProxyList {
44  
45      private int capacity;
46  
47      public LimitedList(int capacity) {
48          this(new ArrayList(), capacity);
49      }
50  
51      public LimitedList(List list, int capacity) {
52          super(list);
53          this.capacity = capacity;
54      }
55  
56      public boolean isFull() {
57          return (this.capacity == size());
58      }
59  
60      public boolean add(Object obj) {
61          if(isFull()) {
62              return false;
63          } else {
64              return super.add(obj);
65          }
66      }
67  
68      public boolean addAll(Collection coll) {
69          if(this.capacity <= size() + coll.size()) {
70              return false;
71          } else {
72              return super.addAll(coll);
73          }
74      }
75  
76      public boolean addAll(int i, Collection coll) {
77          if(this.capacity <= size() + coll.size()) {
78              return false;
79          } else {
80              return super.addAll(i,coll);
81          }
82      }
83  
84      /// TODO
85      public boolean retainAll(Collection coll) {
86          return super.retainAll(coll);
87      }
88  
89      public void add(int i, Object obj) {
90          if(this.capacity == i) {
91              return;
92          } else
93          if(isFull()) {
94              super.remove(this.capacity-1);
95              super.add(i,obj);
96          } else {
97              super.add(i,obj);
98          }
99      }
100 
101     public String toString() {
102         return super.toString();
103     }
104 
105 }