Lucene.Net  3.0.3
Lucene.Net is a port of the Lucene search engine library, written in C# and targeted at .NET runtime users.
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CheckSumIndexInput.cs
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1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one or more
3  * contributor license agreements. See the NOTICE file distributed with
4  * this work for additional information regarding copyright ownership.
5  * The ASF licenses this file to You under the Apache License, Version 2.0
6  * (the "License"); you may not use this file except in compliance with
7  * the License. You may obtain a copy of the License at
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 using System;
19 using Lucene.Net.Support;
20 
21 namespace Lucene.Net.Store
22 {
23 
24  /// <summary>Writes bytes through to a primary IndexOutput, computing
25  /// checksum as it goes. Note that you cannot use seek().
26  /// </summary>
28  {
29  internal IndexInput main;
30  internal IChecksum digest;
31 
32  private bool isDisposed;
33 
35  {
36  this.main = main;
37  digest = new CRC32();
38  }
39 
40  public override byte ReadByte()
41  {
42  byte b = main.ReadByte();
43  digest.Update(b);
44  return b;
45  }
46 
47  public override void ReadBytes(byte[] b, int offset, int len)
48  {
49  main.ReadBytes(b, offset, len);
50  digest.Update(b, offset, len);
51  }
52 
53  public virtual long Checksum
54  {
55  get { return digest.Value; }
56  }
57 
58  protected override void Dispose(bool disposing)
59  {
60  if (isDisposed) return;
61 
62  if (disposing)
63  {
64  if (main != null)
65  {
66  main.Dispose();
67  }
68  }
69 
70  main = null;
71  isDisposed = true;
72  }
73 
74  public override long FilePointer
75  {
76  get { return main.FilePointer; }
77  }
78 
79  public override void Seek(long pos)
80  {
81  throw new System.SystemException("not allowed");
82  }
83 
84  public override long Length()
85  {
86  return main.Length();
87  }
88  }
89 }