1 package org.apache.maven.doxia.util;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 /*
23 * Originally from org.apache.doxia.module.apt.AptReaderSource. It was modified
24 * to get unget support
25 */
26
27 import java.io.IOException;
28 import java.io.LineNumberReader;
29 import java.io.Reader;
30
31 import org.apache.maven.doxia.parser.ParseException;
32 import org.codehaus.plexus.util.IOUtil;
33
34 /**
35 * {@link ByLineSource} default implementation
36 */
37 public class ByLineReaderSource implements ByLineSource
38 {
39 /**
40 * reader
41 */
42 private LineNumberReader reader;
43
44 /**
45 * current line number
46 */
47 private int lineNumber;
48
49 /**
50 * holds the last line returned by getNextLine()
51 */
52 private String lastLine;
53
54 /**
55 * <code>true</code> if ungetLine() was called and no getNextLine() was
56 * called
57 */
58 private boolean ungetted = false;
59
60 private String name;
61
62 /**
63 * Creates the ByLineReaderSource.
64 *
65 * @param in real source :)
66 */
67 public ByLineReaderSource( final Reader in )
68 {
69 this( in, "" );
70 }
71
72 /**
73 * <p>Constructor for ByLineReaderSource.</p>
74 *
75 * @param in a {@link java.io.Reader} object.
76 * @param name a {@link java.lang.String} object.
77 */
78 public ByLineReaderSource( final Reader in, final String name )
79 {
80 this.reader = new LineNumberReader( in );
81
82 this.name = name;
83
84 this.lineNumber = -1;
85 }
86
87 /**
88 * {@inheritDoc}
89 *
90 * @return a {@link java.lang.String} object.
91 * @throws org.apache.maven.doxia.parser.ParseException if any.
92 */
93 public final String getNextLine() throws ParseException
94 {
95 if ( reader == null )
96 {
97 return null;
98 }
99
100 if ( ungetted )
101 {
102 ungetted = false;
103 return lastLine;
104 }
105
106 String line;
107
108 try
109 {
110 line = reader.readLine();
111 if ( line == null )
112 {
113 reader.close();
114 reader = null;
115 }
116 else
117 {
118 lineNumber = reader.getLineNumber();
119 }
120 }
121 catch ( IOException e )
122 {
123 throw new ParseException( e, lineNumber, 0 );
124 }
125
126 lastLine = line;
127
128 return line;
129 }
130
131 /**
132 * {@inheritDoc}
133 *
134 * @return a {@link java.lang.String} object.
135 */
136 public final String getName()
137 {
138 return name;
139 }
140
141 /**
142 * {@inheritDoc}
143 *
144 * @return a int.
145 */
146 public final int getLineNumber()
147 {
148 return lineNumber;
149 }
150
151 /**
152 * {@inheritDoc}
153 */
154 public final void close()
155 {
156 IOUtil.close( reader );
157 reader = null;
158 }
159
160 /**
161 * {@inheritDoc}
162 */
163 public final void ungetLine()
164 {
165 if ( ungetted )
166 {
167 throw new IllegalStateException( "we support only one level of ungetLine()" );
168 }
169 ungetted = true;
170 }
171
172 /** {@inheritDoc} */
173 public final void unget( final String s )
174 {
175 if ( s == null )
176 {
177 throw new IllegalArgumentException( "argument can't be null" );
178 }
179 if ( s.length() != 0 )
180 {
181 ungetLine();
182 lastLine = s;
183 }
184 }
185 }