blob: 039f841c3ccddd685272a28b2a00271d65cf3855 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
namespace Lucene.Net.Analysis
{
/// <summary> Subclasses of CharFilter can be chained to filter CharStream.
/// They can be used as <see cref="System.IO.TextReader" /> with additional offset
/// correction. <see cref="Tokenizer" />s will automatically use <see cref="CorrectOffset" />
/// if a CharFilter/CharStream subclass is used.
///
/// </summary>
/// <version> $Id$
///
/// </version>
public abstract class CharFilter : CharStream
{
private long currentPosition = -1;
private bool isDisposed;
protected internal CharStream input;
protected internal CharFilter(CharStream in_Renamed) : base(in_Renamed)
{
input = in_Renamed;
}
/// <summary>Subclass may want to override to correct the current offset.</summary>
/// <param name="currentOff">current offset</param>
/// <returns>corrected offset</returns>
protected internal virtual int Correct(int currentOff)
{
return currentOff;
}
/// <summary> Chains the corrected offset through the input
/// CharFilter.
/// </summary>
public override int CorrectOffset(int currentOff)
{
return input.CorrectOffset(Correct(currentOff));
}
protected override void Dispose(bool disposing)
{
if (isDisposed) return;
if (disposing)
{
if (input != null)
{
input.Close();
}
}
input = null;
isDisposed = true;
base.Dispose(disposing);
}
public override int Read(System.Char[] cbuf, int off, int len)
{
return input.Read(cbuf, off, len);
}
public bool MarkSupported()
{
return input.BaseStream.CanSeek;
}
public void Mark(int readAheadLimit)
{
currentPosition = input.BaseStream.Position;
input.BaseStream.Position = readAheadLimit;
}
public void Reset()
{
input.BaseStream.Position = currentPosition;
}
}
}
|
