1 /*
2 * Copyright 2009 Red Hat, Inc.
3 *
4 * Red Hat licenses this file to you under the Apache License, version 2.0
5 * (the "License"); you may not use this file except in compliance with the
6 * License. You may obtain a copy of the License at:
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package org.jboss.netty.buffer;
17
18
19 /**
20 * Locates an index of data in a {@link ChannelBuffer}.
21 * <p>
22 * This interface enables the sequential search for the data which meets more
23 * complex and dynamic condition than just a simple value matching. Please
24 * refer to {@link ChannelBuffer#indexOf(int, int, ChannelBufferIndexFinder)} and
25 * {@link ChannelBuffer#bytesBefore(int, int, ChannelBufferIndexFinder)}
26 * for more explanation.
27 *
28 * @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
29 * @author <a href="http://gleamynode.net/">Trustin Lee</a>
30 *
31 * @version $Rev: 2080 $, $Date: 2010-01-26 18:04:19 +0900 (Tue, 26 Jan 2010) $
32 *
33 * @apiviz.uses org.jboss.netty.buffer.ChannelBuffer
34 */
35 public interface ChannelBufferIndexFinder {
36
37 /**
38 * Returns {@code true} if and only if the data is found at the specified
39 * {@code guessedIndex} of the specified {@code buffer}.
40 * <p>
41 * The implementation should not perform an operation which raises an
42 * exception such as {@link IndexOutOfBoundsException} nor perform
43 * an operation which modifies the content of the buffer.
44 */
45 boolean find(ChannelBuffer buffer, int guessedIndex);
46
47 /**
48 * Index finder which locates a {@code NUL (0x00)} byte.
49 */
50 static ChannelBufferIndexFinder NUL = new ChannelBufferIndexFinder() {
51 public boolean find(ChannelBuffer buffer, int guessedIndex) {
52 return buffer.getByte(guessedIndex) == 0;
53 }
54 };
55
56 /**
57 * Index finder which locates a non-{@code NUL (0x00)} byte.
58 */
59 static ChannelBufferIndexFinder NOT_NUL = new ChannelBufferIndexFinder() {
60 public boolean find(ChannelBuffer buffer, int guessedIndex) {
61 return buffer.getByte(guessedIndex) != 0;
62 }
63 };
64
65 /**
66 * Index finder which locates a {@code CR ('\r')} byte.
67 */
68 static ChannelBufferIndexFinder CR = new ChannelBufferIndexFinder() {
69 public boolean find(ChannelBuffer buffer, int guessedIndex) {
70 return buffer.getByte(guessedIndex) == '\r';
71 }
72 };
73
74 /**
75 * Index finder which locates a non-{@code CR ('\r')} byte.
76 */
77 static ChannelBufferIndexFinder NOT_CR = new ChannelBufferIndexFinder() {
78 public boolean find(ChannelBuffer buffer, int guessedIndex) {
79 return buffer.getByte(guessedIndex) != '\r';
80 }
81 };
82
83 /**
84 * Index finder which locates a {@code LF ('\n')} byte.
85 */
86 static ChannelBufferIndexFinder LF = new ChannelBufferIndexFinder() {
87 public boolean find(ChannelBuffer buffer, int guessedIndex) {
88 return buffer.getByte(guessedIndex) == '\n';
89 }
90 };
91
92 /**
93 * Index finder which locates a non-{@code LF ('\n')} byte.
94 */
95 static ChannelBufferIndexFinder NOT_LF = new ChannelBufferIndexFinder() {
96 public boolean find(ChannelBuffer buffer, int guessedIndex) {
97 return buffer.getByte(guessedIndex) != '\n';
98 }
99 };
100
101 /**
102 * Index finder which locates a {@code CR ('\r')} or {@code LF ('\n')}.
103 */
104 static ChannelBufferIndexFinder CRLF = new ChannelBufferIndexFinder() {
105 public boolean find(ChannelBuffer buffer, int guessedIndex) {
106 byte b = buffer.getByte(guessedIndex);
107 return b == '\r' || b == '\n';
108 }
109 };
110
111 /**
112 * Index finder which locates a byte which is neither a {@code CR ('\r')}
113 * nor a {@code LF ('\n')}.
114 */
115 static ChannelBufferIndexFinder NOT_CRLF = new ChannelBufferIndexFinder() {
116 public boolean find(ChannelBuffer buffer, int guessedIndex) {
117 byte b = buffer.getByte(guessedIndex);
118 return b != '\r' && b != '\n';
119 }
120 };
121
122 /**
123 * Index finder which locates a linear whitespace
124 * ({@code ' '} and {@code '\t'}).
125 */
126 static ChannelBufferIndexFinder LINEAR_WHITESPACE = new ChannelBufferIndexFinder() {
127 public boolean find(ChannelBuffer buffer, int guessedIndex) {
128 byte b = buffer.getByte(guessedIndex);
129 return b == ' ' || b == '\t';
130 }
131 };
132
133 /**
134 * Index finder which locates a byte which is not a linear whitespace
135 * (neither {@code ' '} nor {@code '\t'}).
136 */
137 static ChannelBufferIndexFinder NOT_LINEAR_WHITESPACE = new ChannelBufferIndexFinder() {
138 public boolean find(ChannelBuffer buffer, int guessedIndex) {
139 byte b = buffer.getByte(guessedIndex);
140 return b != ' ' && b != '\t';
141 }
142 };
143 }