HttpVersion.java
1 /* 2 * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/HttpVersion.java,v 1.6 2004/12/20 19:52:50 olegk Exp $ 3 * $Revision: 480424 $ 4 * $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $ 5 * 6 * ==================================================================== 7 * 8 * Licensed to the Apache Software Foundation (ASF) under one or more 9 * contributor license agreements. See the NOTICE file distributed with 10 * this work for additional information regarding copyright ownership. 11 * The ASF licenses this file to You under the Apache License, Version 2.0 12 * (the "License"); you may not use this file except in compliance with 13 * 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, software 18 * distributed under the License is distributed on an "AS IS" BASIS, 19 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 20 * See the License for the specific language governing permissions and 21 * limitations under the License. 22 * ==================================================================== 23 * 24 * This software consists of voluntary contributions made by many 25 * individuals on behalf of the Apache Software Foundation. For more 26 * information on the Apache Software Foundation, please see 27 * <http://www.apache.org/>. 28 * 29 */ 30 31 package org.apache.commons.httpclient; 32 33 /** 34 * <p>HTTP version, as specified in RFC 2616.</p> 35 * <p> 36 * HTTP uses a "<major>.<minor>" numbering scheme to indicate 37 * versions of the protocol. The protocol versioning policy is intended to 38 * allow the sender to indicate the format of a message and its capacity for 39 * understanding further HTTP communication, rather than the features 40 * obtained via that communication. No change is made to the version 41 * number for the addition of message components which do not affect 42 * communication behavior or which only add to extensible field values. 43 * The <minor> number is incremented when the changes made to the 44 * protocol add features which do not change the general message parsing 45 * algorithm, but which may add to the message semantics and imply 46 * additional capabilities of the sender. The <major> number is 47 * incremented when the format of a message within the protocol is 48 * changed. See RFC 2145 [36] for a fuller explanation. 49 * </p> 50 * <p> 51 * The version of an HTTP message is indicated by an HTTP-Version field 52 * in the first line of the message. 53 * </p> 54 * <pre> 55 * HTTP-Version = "HTTP" "/" 1*DIGIT "." 1*DIGIT 56 * </pre> 57 * <p> 58 * Note that the major and minor numbers MUST be treated as separate 59 * integers and that each MAY be incremented higher than a single digit. 60 * Thus, HTTP/2.4 is a lower version than HTTP/2.13, which in turn is 61 * lower than HTTP/12.3. Leading zeros MUST be ignored by recipients and 62 * MUST NOT be sent. 63 * </p> 64 * 65 * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a> 66 * 67 * @version $Revision: 480424 $ $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $ 68 * 69 * @since 3.0 70 */ 71 public class HttpVersion implements Comparable { 72 73 /** Major version number of the HTTP protocol */ 74 private int major = 0; 75 76 /** Minor version number of the HTTP protocol */ 77 private int minor = 0; 78 79 /** HTTP protocol version 0.9 */ 80 public static final HttpVersion HTTP_0_9 = new HttpVersion(0, 9); 81 82 /** HTTP protocol version 1.0 */ 83 public static final HttpVersion HTTP_1_0 = new HttpVersion(1, 0); 84 85 /** HTTP protocol version 1.1 */ 86 public static final HttpVersion HTTP_1_1 = new HttpVersion(1, 1); 87 88 /** 89 * Create an HTTP protocol version designator. 90 * 91 * @param major the major version number of the HTTP protocol 92 * @param minor the minor version number of the HTTP protocol 93 * 94 * @throws IllegalArgumentException if either major or minor version number is negative 95 */ 96 public HttpVersion(int major, int minor) { 97 if (major < 0) { 98 throw new IllegalArgumentException("HTTP major version number may not be negative"); 99 } 100 this.major = major; 101 if (minor < 0) { 102 throw new IllegalArgumentException("HTTP minor version number may not be negative"); 103 } 104 this.minor = minor; 105 } 106 107 /** 108 * Returns the major version number of the HTTP protocol. 109 * 110 * @return the major version number. 111 */ 112 public int getMajor() { 113 return major; 114 } 115 116 /** 117 * Returns the minor version number of the HTTP protocol. 118 * 119 * @return the minor version number. 120 */ 121 public int getMinor() { 122 return minor; 123 } 124 125 /** 126 * @see java.lang.Object#hashCode() 127 */ 128 public int hashCode() { 129 return this.major * 100000 + this.minor; 130 } 131 132 /** 133 * @see java.lang.Object#equals(java.lang.Object) 134 */ 135 public boolean equals(Object obj) { 136 if (this == obj) { 137 return true; 138 } 139 if (!(obj instanceof HttpVersion)) { 140 return false; 141 } 142 return equals((HttpVersion)obj); 143 } 144 145 /** 146 * Compares this HTTP protocol version with another one. 147 * 148 * @param anotherVer the version to be compared with. 149 * 150 * @return a negative integer, zero, or a positive integer as this version is less than, 151 * equal to, or greater than the specified version. 152 */ 153 public int compareTo(HttpVersion anotherVer) { 154 if (anotherVer == null) { 155 throw new IllegalArgumentException("Version parameter may not be null"); 156 } 157 int delta = getMajor() - anotherVer.getMajor(); 158 if (delta == 0) { 159 delta = getMinor() - anotherVer.getMinor(); 160 } 161 return delta; 162 } 163 164 /** 165 * @see java.lang.Comparable#compareTo(java.lang.Object) 166 */ 167 public int compareTo(Object o) { 168 return compareTo((HttpVersion)o); 169 } 170 171 /** 172 * Test if the HTTP protocol version is equal to the given number. 173 * 174 * @return <tt>true</tt> if HTTP protocol version is given to the given number, 175 * <tt>false</tt> otherwise. 176 */ 177 public boolean equals(HttpVersion version) { 178 return compareTo(version) == 0; 179 } 180 181 /** 182 * Test if the HTTP protocol version is greater or equal to the given number. 183 * 184 * @return <tt>true</tt> if HTTP protocol version is greater or equal given to the 185 * given number, <tt>false</tt> otherwise. 186 */ 187 public boolean greaterEquals(HttpVersion version) { 188 return compareTo(version) >= 0; 189 } 190 191 /** 192 * Test if the HTTP protocol version is less or equal to the given number. 193 * 194 * @return <tt>true</tt> if HTTP protocol version is less or equal to given to the 195 * given number, <tt>false</tt> otherwise. 196 */ 197 public boolean lessEquals(HttpVersion version) { 198 return compareTo(version) <= 0; 199 } 200 201 /** 202 * @see java.lang.Object#toString() 203 */ 204 public String toString() { 205 StringBuffer buffer = new StringBuffer(); 206 buffer.append("HTTP/"); 207 buffer.append(this.major); 208 buffer.append('.'); 209 buffer.append(this.minor); 210 return buffer.toString(); 211 } 212 213 /** 214 * Parses the textual representation of the given HTTP protocol version. 215 * 216 * @return HTTP protocol version. 217 * 218 * @throws ProtocolException if the string is not a valid HTTP protocol version. 219 */ 220 public static HttpVersion parse(final String s) throws ProtocolException { 221 if (s == null) { 222 throw new IllegalArgumentException("String may not be null"); 223 } 224 if (!s.startsWith("HTTP/")) { 225 throw new ProtocolException("Invalid HTTP version string: " + s); 226 } 227 int major, minor; 228 229 int i1 = "HTTP/".length(); 230 int i2 = s.indexOf(".", i1); 231 if (i2 == -1) { 232 throw new ProtocolException("Invalid HTTP version number: " + s); 233 } 234 try { 235 major = Integer.parseInt(s.substring(i1, i2)); 236 } catch (NumberFormatException e) { 237 throw new ProtocolException("Invalid HTTP major version number: " + s); 238 } 239 i1 = i2 + 1; 240 i2 = s.length(); 241 try { 242 minor = Integer.parseInt(s.substring(i1, i2)); 243 } catch (NumberFormatException e) { 244 throw new ProtocolException("Invalid HTTP minor version number: " + s); 245 } 246 return new HttpVersion(major, minor); 247 } 248 249 }