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1   // ========================================================================
2   // Copyright 2004-2005 Mort Bay Consulting Pty. Ltd.
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   // http://www.apache.org/licenses/LICENSE-2.0
8   // Unless required by applicable law or agreed to in writing, software
9   // distributed under the License is distributed on an "AS IS" BASIS,
10  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11  // See the License for the specific language governing permissions and
12  // limitations under the License.
13  // ========================================================================
14  
15  package org.mortbay.io;
16  
17  import java.util.ArrayList;
18  import java.util.HashMap;
19  import java.util.Map.Entry;
20  
21  import org.mortbay.util.StringMap;
22  
23  /* ------------------------------------------------------------------------------- */
24  /** 
25   * Stores a collection of {@link Buffer} objects.
26   * Buffers are stored in an ordered collection and can retreived by index or value
27   * @author gregw
28   */
29  public class BufferCache
30  {
31      private HashMap _bufferMap=new HashMap();
32      private StringMap _stringMap=new StringMap(StringMap.CASE_INSENSTIVE);
33      private ArrayList _index= new ArrayList();
34  
35      /* ------------------------------------------------------------------------------- */
36      /** Add a buffer to the cache at the specified index.
37       * @param value The content of the buffer.
38       */
39      public CachedBuffer add(String value, int ordinal)
40      {
41          CachedBuffer buffer= new CachedBuffer(value, ordinal);
42          _bufferMap.put(buffer, buffer);
43          _stringMap.put(value, buffer);
44          while ((ordinal - _index.size()) > 0)
45              _index.add(null);
46          _index.add(ordinal, buffer);
47          return buffer;
48      }
49  
50      public CachedBuffer get(int ordinal)
51      {
52          if (ordinal < 0 || ordinal >= _index.size())
53              return null;
54          return (CachedBuffer)_index.get(ordinal);
55      }
56  
57      public CachedBuffer get(Buffer buffer)
58      {
59          return (CachedBuffer)_bufferMap.get(buffer);
60      }
61  
62      public CachedBuffer get(String value)
63      {
64          return (CachedBuffer)_stringMap.get(value);
65      }
66  
67      public Buffer lookup(Buffer buffer)
68      {
69          Buffer b= get(buffer);
70          if (b == null)
71          {
72              if (buffer instanceof Buffer.CaseInsensitve)
73                  return buffer;
74              return new View.CaseInsensitive(buffer);
75          }
76  
77          return b;
78      }
79      
80      public CachedBuffer getBest(byte[] value, int offset, int maxLength)
81      {
82          Entry entry = _stringMap.getBestEntry(value, offset, maxLength);
83          if (entry!=null)
84              return (CachedBuffer)entry.getValue();
85          return null;
86      }
87  
88      public Buffer lookup(String value)
89      {
90          Buffer b= get(value);
91          if (b == null)
92          {
93              return new CachedBuffer(value,-1);
94          }
95          return b;
96      }
97  
98      public String toString(Buffer buffer)
99      {
100         return lookup(buffer).toString();
101     }
102 
103     public int getOrdinal(Buffer buffer)
104     {
105         if (buffer instanceof CachedBuffer)
106             return ((CachedBuffer)buffer).getOrdinal();
107         buffer=lookup(buffer);
108         if (buffer!=null && buffer instanceof CachedBuffer)
109             return ((CachedBuffer)buffer).getOrdinal();
110         return -1;
111     }
112     
113     public static class CachedBuffer extends ByteArrayBuffer.CaseInsensitive
114     {
115         private int _ordinal;
116         private HashMap _associateMap=null;
117         
118         public CachedBuffer(String value, int ordinal)
119         {
120             super(value);
121             _ordinal= ordinal;
122         }
123 
124         public int getOrdinal()
125         {
126             return _ordinal;
127         }
128 
129         public CachedBuffer getAssociate(Object key)
130         {
131             if (_associateMap==null)
132                 return null;
133             return (CachedBuffer)_associateMap.get(key);
134         }
135         
136         public void setAssociate(Object key, CachedBuffer associate)
137         {
138             // TODO should be synchronized - but lets try without
139             if (_associateMap==null)
140                 _associateMap=new HashMap();
141             _associateMap.put(key,associate);
142         }
143     }
144     
145     
146     public String toString()
147     {
148         return "CACHE["+
149         	"bufferMap="+_bufferMap+
150         	",stringMap="+_stringMap+
151         	",index="+_index+
152         	"]";
153     }
154 }