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Java > Open Source Codes > com > caucho > vfs > SpyRandomAccessStream


1 /*
2  * Copyright (c) 1998-2006 Caucho Technology -- all rights reserved
3  *
4  * This file is part of Resin(R) Open Source
5  *
6  * Each copy or derived work must preserve the copyright notice and this
7  * notice unmodified.
8  *
9  * Resin Open Source is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * Resin Open Source is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
17  * of NON-INFRINGEMENT. See the GNU General Public License for more
18  * details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with Resin Open Source; if not, write to the
22  *
23  * Free Software Foundation, Inc.
24  * 59 Temple Place, Suite 330
25  * Boston, MA 02111-1307 USA
26  *
27  * @author Scott Ferguson
28  */
29
30 package com.caucho.vfs;
31
32 import java.io.IOException JavaDoc;
33 import java.io.InputStream JavaDoc;
34 import java.io.OutputStream JavaDoc;
35 import java.util.logging.Logger JavaDoc;
36
37 /**
38  * Reads from a file in a random-access fashion.
39  */
40 public class SpyRandomAccessStream extends RandomAccessStream {
41   private static final Logger JavaDoc log
42     = Logger.getLogger(SpyRandomAccessStream.class.getName());
43   
44   private RandomAccessStream _file;
45
46   public SpyRandomAccessStream(RandomAccessStream file)
47   {
48     _file = file;
49   }
50   
51   /**
52    * Returns the length.
53    */
54   public long getLength()
55     throws IOException JavaDoc
56   {
57     return _file.getLength();
58   }
59   
60   /**
61    * Reads a block from a given location.
62    */
63   public int read(byte []buffer, int offset, int length)
64     throws IOException JavaDoc
65   {
66     log.info("random-read(0x" + Long.toHexString(getFilePointer()) + "," +
67              length + ")");
68     
69     return _file.read(buffer, offset, length);
70   }
71
72   /**
73    * Reads a block from a given location.
74    */
75   public int read(long fileOffset, byte []buffer, int offset, int length)
76     throws IOException JavaDoc
77   {
78     log.info("random-read(0x" + Long.toHexString(fileOffset) + "," +
79              length + ")");
80     
81     return _file.read(fileOffset, buffer, offset, length);
82   }
83
84   public void write(byte []buffer, int offset, int length)
85     throws IOException JavaDoc
86   {
87     log.info("random-write(0x" + Long.toHexString(getFilePointer()) + "," +
88              length + ")");
89     
90     _file.write(buffer, offset, length);
91   }
92
93   /**
94    * Writes a block from a given location.
95    */
96   public void write(long fileOffset, byte []buffer, int offset, int length)
97     throws IOException JavaDoc
98   {
99     log.info("random-write(0x" + Long.toHexString(fileOffset) + "," +
100              length + ")");
101     
102     _file.write(fileOffset, buffer, offset, length);
103   }
104
105     /**
106    * Seeks to the given position in the file.
107    */
108   public boolean seek(long position)
109   {
110     log.info("random-seek(0x" + position + ")");
111
112     return _file.seek(position);
113   }
114
115   /**
116    * Returns an OutputStream for this stream.
117    */
118   public OutputStream JavaDoc getOutputStream()
119     throws IOException JavaDoc
120   {
121     return _file.getOutputStream();
122   }
123
124   /**
125    * Returns an InputStream for this stream.
126    */
127   public InputStream JavaDoc getInputStream()
128     throws IOException JavaDoc
129   {
130     return _file.getInputStream();
131   }
132
133   /**
134    * Read a byte from the file, advancing the pointer.
135    */
136   public int read()
137     throws IOException JavaDoc
138   {
139     log.info("random-read(0x" + Long.toHexString(getFilePointer()) + ",1)");
140
141     return _file.read();
142   }
143
144   /**
145    * Write a byte to the file, advancing the pointer.
146    */
147   public void write(int b)
148     throws IOException JavaDoc
149   {
150     log.info("random-write(0x" + Long.toHexString(getFilePointer()) + ",1)");
151     
152     _file.write(b);
153   }
154
155   /**
156    * Returns the current position of the file pointer.
157    */
158   public long getFilePointer()
159     throws IOException JavaDoc
160   {
161     return _file.getFilePointer();
162   }
163
164   /**
165    * Closes the stream.
166    */
167   public void close() throws IOException JavaDoc
168   {
169     _file.close();
170   }
171 }
172
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