1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.message;
29
30 import java.io.Serializable;
31
32 import org.apache.http.FormattedHeader;
33 import org.apache.http.HeaderElement;
34 import org.apache.http.ParseException;
35 import org.apache.http.annotation.NotThreadSafe;
36 import org.apache.http.util.CharArrayBuffer;
37
38 /**
39 * This class represents a raw HTTP header whose content is parsed 'on demand'
40 * only when the header value needs to be consumed.
41 *
42 * @since 4.0
43 */
44 @NotThreadSafe
45 public class BufferedHeader implements FormattedHeader, Cloneable, Serializable {
46
47 private static final long serialVersionUID = -2768352615787625448L;
48
49 /**
50 * Header name.
51 */
52 private final String name;
53
54 /**
55 * The buffer containing the entire header line.
56 */
57 private final CharArrayBuffer buffer;
58
59 /**
60 * The beginning of the header value in the buffer
61 */
62 private final int valuePos;
63
64
65 /**
66 * Creates a new header from a buffer.
67 * The name of the header will be parsed immediately,
68 * the value only if it is accessed.
69 *
70 * @param buffer the buffer containing the header to represent
71 *
72 * @throws ParseException in case of a parse error
73 */
74 public BufferedHeader(final CharArrayBuffer buffer)
75 throws ParseException {
76
77 super();
78 if (buffer == null) {
79 throw new IllegalArgumentException
80 ("Char array buffer may not be null");
81 }
82 int colon = buffer.indexOf(':');
83 if (colon == -1) {
84 throw new ParseException
85 ("Invalid header: " + buffer.toString());
86 }
87 String s = buffer.substringTrimmed(0, colon);
88 if (s.length() == 0) {
89 throw new ParseException
90 ("Invalid header: " + buffer.toString());
91 }
92 this.buffer = buffer;
93 this.name = s;
94 this.valuePos = colon + 1;
95 }
96
97
98 public String getName() {
99 return this.name;
100 }
101
102 public String getValue() {
103 return this.buffer.substringTrimmed(this.valuePos, this.buffer.length());
104 }
105
106 public HeaderElement[] getElements() throws ParseException {
107 ParserCursor cursor = new ParserCursor(0, this.buffer.length());
108 cursor.updatePos(this.valuePos);
109 return BasicHeaderValueParser.DEFAULT
110 .parseElements(this.buffer, cursor);
111 }
112
113 public int getValuePos() {
114 return this.valuePos;
115 }
116
117 public CharArrayBuffer getBuffer() {
118 return this.buffer;
119 }
120
121 @Override
122 public String toString() {
123 return this.buffer.toString();
124 }
125
126 @Override
127 public Object clone() throws CloneNotSupportedException {
128 // buffer is considered immutable
129 // no need to make a copy of it
130 return super.clone();
131 }
132
133 }