HttpVersion.java revision 069490a5ca2fd1988d29daf45d892f47ad665115 
1/*
2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/HttpVersion.java $
3 * $Revision: 609106 $
4 * $Date: 2008-01-05 01:15:42 -0800 (Sat, 05 Jan 2008) $
5 *
6 * ====================================================================
7 * Licensed to the Apache Software Foundation (ASF) under one
8 * or more contributor license agreements.  See the NOTICE file
9 * distributed with this work for additional information
10 * regarding copyright ownership.  The ASF licenses this file
11 * to you under the Apache License, Version 2.0 (the
12 * "License"); you may not use this file except in compliance
13 * with the License.  You may obtain a copy of the License at
14 *
15 *   http://www.apache.org/licenses/LICENSE-2.0
16 *
17 * Unless required by applicable law or agreed to in writing,
18 * software distributed under the License is distributed on an
19 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
20 * KIND, either express or implied.  See the License for the
21 * specific language governing permissions and limitations
22 * under the License.
23 * ====================================================================
24 *
25 * This software consists of voluntary contributions made by many
26 * individuals on behalf of the Apache Software Foundation.  For more
27 * information on the Apache Software Foundation, please see
28 * <http://www.apache.org/>.
29 *
30 */
31
32package org.apache.http;
33
34import java.io.Serializable;
35
36/**
37 * Represents an HTTP version, as specified in RFC 2616.
38 *
39 * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
40 *
41 * @version $Revision: 609106 $ $Date: 2008-01-05 01:15:42 -0800 (Sat, 05 Jan 2008) $
42 */
43public final class HttpVersion extends ProtocolVersion
44    implements Serializable {
45
46    private static final long serialVersionUID = -5856653513894415344L;
47
48    /** The protocol name. */
49    public static final String HTTP = "HTTP";
50
51    /** HTTP protocol version 0.9 */
52    public static final HttpVersion HTTP_0_9 = new HttpVersion(0, 9);
53
54    /** HTTP protocol version 1.0 */
55    public static final HttpVersion HTTP_1_0 = new HttpVersion(1, 0);
56
57    /** HTTP protocol version 1.1 */
58    public static final HttpVersion HTTP_1_1 = new HttpVersion(1, 1);
59
60
61    /**
62     * Create an HTTP protocol version designator.
63     *
64     * @param major   the major version number of the HTTP protocol
65     * @param minor   the minor version number of the HTTP protocol
66     *
67     * @throws IllegalArgumentException if either major or minor version number is negative
68     */
69    public HttpVersion(int major, int minor) {
70        super(HTTP, major, minor);
71    }
72
73
74    /**
75     * Obtains a specific HTTP version.
76     *
77     * @param major     the major version
78     * @param minor     the minor version
79     *
80     * @return  an instance of {@link HttpVersion} with the argument version
81     */
82    public ProtocolVersion forVersion(int major, int minor) {
83
84        if ((major == this.major) && (minor == this.minor)) {
85            return this;
86        }
87
88        if (major == 1) {
89            if (minor == 0) {
90                return HTTP_1_0;
91            }
92            if (minor == 1) {
93                return HTTP_1_1;
94            }
95        }
96        if ((major == 0) && (minor == 9)) {
97            return HTTP_0_9;
98        }
99
100        // argument checking is done in the constructor
101        return new HttpVersion(major, minor);
102    }
103
104}
105