1  /*
  2   * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/StatusLine.java,v 1.14 2004/07/19 20:24:21 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   * Represents a Status-Line as returned from a HTTP server.
 35   *
 36   * <a href="http://www.ietf.org/rfc/rfc2616.txt">RFC2616</a> states
 37   * the following regarding the Status-Line:
 38   * <pre>
 39   * 6.1 Status-Line
 40   *
 41   *  The first line of a Response message is the Status-Line, consisting
 42   *  of the protocol version followed by a numeric status code and its
 43   *  associated textual phrase, with each element separated by SP
 44   *  characters. No CR or LF is allowed except in the final CRLF sequence.
 45   *
 46   *      Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase CRLF
 47   * </pre>
 48   * <p>
 49   * This class is immutable and is inherently thread safe.
 50   *
 51   * @see HttpStatus
 52   * @author <a href="mailto:jsdever@apache.org">Jeff Dever</a>
 53   * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
 54   * @version $Id: StatusLine.java 480424 2006-11-29 05:56:49Z bayard $
 55   * @since 2.0
 56   */
 57  public class StatusLine {
 58  
 59      // ----------------------------------------------------- Instance Variables
 60  
 61      /** The original Status-Line. */
 62      private final String statusLine;
 63  
 64      /** The HTTP-Version. */
 65      private final String httpVersion;
 66  
 67      /** The Status-Code. */
 68      private final int statusCode;
 69  
 70      /** The Reason-Phrase. */
 71      private final String reasonPhrase;
 72  
 73  
 74      // ----------------------------------------------------------- Constructors
 75  
 76      /**
 77       * Default constructor.
 78       *
 79       * @param statusLine the status line returned from the HTTP server
 80       * @throws HttpException if the status line is invalid
 81       */
 82      public StatusLine(final String statusLine) throws HttpException {
 83  
 84          int length = statusLine.length();
 85          int at = 0;
 86          int start = 0;
 87          try {
 88              while (Character.isWhitespace(statusLine.charAt(at))) {
 89                  ++at;
 90                  ++start;
 91              }
 92              if (!"HTTP".equals(statusLine.substring(at, at += 4))) {
 93                  throw new HttpException("Status-Line '" + statusLine 
 94                      + "' does not start with HTTP");
 95              }
 96              //handle the HTTP-Version
 97              at = statusLine.indexOf(" ", at);
 98              if (at <= 0) {
 99                  throw new ProtocolException(
100                          "Unable to parse HTTP-Version from the status line: '"
101                          + statusLine + "'");
102              }
103              this.httpVersion = (statusLine.substring(start, at)).toUpperCase();
104  
105              //advance through spaces
106              while (statusLine.charAt(at) == ' ') {
107                  at++;
108              }
109  
110              //handle the Status-Code
111              int to = statusLine.indexOf(" ", at);
112              if (to < 0) {
113                  to = length;
114              }
115              try {
116                  this.statusCode = Integer.parseInt(statusLine.substring(at, to));
117              } catch (NumberFormatException e) {
118                  throw new ProtocolException(
119                      "Unable to parse status code from status line: '" 
120                      + statusLine + "'");
121              }
122              //handle the Reason-Phrase
123              at = to + 1;
124              if (at < length) {
125                  this.reasonPhrase = statusLine.substring(at).trim();
126              } else {
127                  this.reasonPhrase = "";
128              }
129          } catch (StringIndexOutOfBoundsException e) {
130              throw new HttpException("Status-Line '" + statusLine + "' is not valid"); 
131          }
132          //save the original Status-Line
133          this.statusLine = statusLine;
134      }
135  
136  
137      // --------------------------------------------------------- Public Methods
138  
139      /**
140       * @return the Status-Code
141       */
142      public final int getStatusCode() {
143          return statusCode;
144      }
145  
146      /**
147       * @return the HTTP-Version
148       */
149      public final String getHttpVersion() {
150          return httpVersion;
151      }
152  
153      /**
154       * @return the Reason-Phrase
155       */
156      public final String getReasonPhrase() {
157          return reasonPhrase;
158      }
159  
160      /**
161       * Return a string representation of this object.
162       * @return a string represenation of this object.
163       */
164      public final String toString() {
165          return statusLine;
166      }
167  
168      /**
169       * Tests if the string starts with 'HTTP' signature.
170       * @param s string to test
171       * @return <tt>true</tt> if the line starts with 'HTTP' 
172       *   signature, <tt>false</tt> otherwise.
173       */
174      public static boolean startsWithHTTP(final String s) {
175          try {
176              int at = 0;
177              while (Character.isWhitespace(s.charAt(at))) {
178                  ++at;
179              }
180              return ("HTTP".equals(s.substring(at, at + 4)));
181          } catch (StringIndexOutOfBoundsException e) {
182              return false;
183          }
184      }
185  }