Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||||||
ExtendedReader |
|
| 2.4545454545454546;2.455 |
1 | // Copyright 2004, 2005 The Apache Software Foundation |
|
2 | // |
|
3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
|
4 | // you may not use this file except in compliance with the License. |
|
5 | // You may obtain a copy of the License at |
|
6 | // |
|
7 | // http://www.apache.org/licenses/LICENSE-2.0 |
|
8 | // |
|
9 | // Unless required by applicable law or agreed to in writing, software |
|
10 | // distributed under the License is distributed on an "AS IS" BASIS, |
|
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
|
12 | // See the License for the specific language governing permissions and |
|
13 | // limitations under the License. |
|
14 | ||
15 | package org.apache.tapestry.util.text; |
|
16 | ||
17 | import java.io.IOException; |
|
18 | import java.io.Reader; |
|
19 | ||
20 | /** |
|
21 | * A Reader that provides some additional functionality, such as peek(). |
|
22 | * |
|
23 | * @author mb |
|
24 | * @since 4.0 |
|
25 | */ |
|
26 | public class ExtendedReader extends Reader |
|
27 | { |
|
28 | private Reader _reader; |
|
29 | 94 | private boolean _hasBufferedChar = false; |
30 | private char _bufferedChar; |
|
31 | ||
32 | /** |
|
33 | * Creates a new extended reader that reads from the provided object. |
|
34 | * |
|
35 | * @param in the Reader to get data from |
|
36 | */ |
|
37 | public ExtendedReader(Reader in) |
|
38 | 94 | { |
39 | 94 | _reader = in; |
40 | 94 | } |
41 | ||
42 | /** |
|
43 | * Returns the next character in the stream without actually comitting the read. |
|
44 | * Multiple consequtive invocations of this method should return the same value. |
|
45 | * |
|
46 | * @return the next character waiting in the stream or -1 if the end of the stream is reached |
|
47 | * @throws IOException if an error occurs |
|
48 | */ |
|
49 | public synchronized int peek() throws IOException |
|
50 | { |
|
51 | 134021 | if (!_hasBufferedChar) { |
52 | 64996 | int bufferedChar = read(); |
53 | 64996 | if (bufferedChar < 0) |
54 | 192 | return bufferedChar; |
55 | 64804 | _bufferedChar = (char) bufferedChar; |
56 | 64804 | _hasBufferedChar = true; |
57 | } |
|
58 | 133829 | return _bufferedChar; |
59 | } |
|
60 | ||
61 | /** |
|
62 | * Determines whether the end of the stream is reached. |
|
63 | * |
|
64 | * @return true if at the end of stream |
|
65 | * @throws IOException if an error occurs |
|
66 | */ |
|
67 | public synchronized boolean isEndOfStream() throws IOException |
|
68 | { |
|
69 | 57417 | return peek() < 0; |
70 | } |
|
71 | ||
72 | /** |
|
73 | * Skips the next characters until a character that does not match the provided rule is reached. |
|
74 | * |
|
75 | * @param matcher the object determining whether a character should be skipped |
|
76 | * @throws IOException if an error occurs |
|
77 | */ |
|
78 | public synchronized void skipCharacters(ICharacterMatcher matcher) throws IOException |
|
79 | { |
|
80 | while (true) { |
|
81 | 57417 | if (isEndOfStream()) |
82 | 92 | break; |
83 | 57325 | char ch = (char) peek(); |
84 | 57325 | if (!matcher.matches(ch)) |
85 | 4509 | break; |
86 | 52816 | read(); |
87 | 52816 | } |
88 | 4601 | } |
89 | ||
90 | /** |
|
91 | * Reads the next characters until a character that does not match the provided rule is reached. |
|
92 | * |
|
93 | * @param matcher the object determining whether a character should be read |
|
94 | * @return the string of characters read |
|
95 | * @throws IOException if an error occurs |
|
96 | */ |
|
97 | public synchronized String readCharacters(ICharacterMatcher matcher) throws IOException |
|
98 | { |
|
99 | 0 | StringBuffer buf = new StringBuffer(); |
100 | while (true) { |
|
101 | 0 | if (isEndOfStream()) |
102 | 0 | break; |
103 | 0 | char ch = (char) peek(); |
104 | 0 | if (!matcher.matches(ch)) |
105 | 0 | break; |
106 | 0 | buf.append(read()); |
107 | 0 | } |
108 | 0 | return buf.toString(); |
109 | } |
|
110 | ||
111 | /** |
|
112 | * @see java.io.FilterReader#read(char[], int, int) |
|
113 | */ |
|
114 | public synchronized int read(char[] cbuf, int off, int len) throws IOException |
|
115 | { |
|
116 | 129819 | int offset = off; |
117 | 129819 | if (len <= 0) |
118 | 0 | return 0; |
119 | 129819 | int readLength = len; |
120 | ||
121 | 129819 | boolean extraChar = _hasBufferedChar; |
122 | 129819 | if (_hasBufferedChar) { |
123 | 64804 | _hasBufferedChar = false; |
124 | 64804 | cbuf[offset++] = _bufferedChar; |
125 | 64804 | readLength--; |
126 | } |
|
127 | ||
128 | 129819 | int read = _reader.read(cbuf, offset, readLength); |
129 | 129819 | if (extraChar) |
130 | 64804 | read++; |
131 | 129819 | return read; |
132 | } |
|
133 | ||
134 | /** |
|
135 | * @see java.io.FilterReader#ready() |
|
136 | */ |
|
137 | public synchronized boolean ready() throws IOException |
|
138 | { |
|
139 | 0 | if (_hasBufferedChar) |
140 | 0 | return true; |
141 | 0 | return _reader.ready(); |
142 | } |
|
143 | ||
144 | /** |
|
145 | * @see java.io.FilterReader#markSupported() |
|
146 | */ |
|
147 | public synchronized boolean markSupported() |
|
148 | { |
|
149 | 0 | return false; |
150 | } |
|
151 | ||
152 | /** |
|
153 | * @see java.io.FilterReader#reset() |
|
154 | */ |
|
155 | public synchronized void reset() throws IOException |
|
156 | { |
|
157 | 0 | _hasBufferedChar = false; |
158 | 0 | _reader.reset(); |
159 | 0 | } |
160 | ||
161 | /** |
|
162 | * @see java.io.FilterReader#skip(long) |
|
163 | */ |
|
164 | public synchronized long skip(long n) throws IOException |
|
165 | { |
|
166 | 0 | long skipChars = n; |
167 | 0 | if (_hasBufferedChar && skipChars > 0) { |
168 | 0 | _hasBufferedChar = false; |
169 | 0 | skipChars--; |
170 | } |
|
171 | 0 | return _reader.skip(skipChars); |
172 | } |
|
173 | ||
174 | /** |
|
175 | * @see java.io.Reader#close() |
|
176 | */ |
|
177 | public synchronized void close() throws IOException |
|
178 | { |
|
179 | 0 | _hasBufferedChar = false; |
180 | 0 | _reader.close(); |
181 | 0 | } |
182 | ||
183 | } |