Source for org.apache.commons.httpclient.HeaderGroup

   1: /*
   2:  * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/HeaderGroup.java,v 1.8 2004/05/13 04:03:25 mbecke 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: import java.util.ArrayList;
  34: import java.util.Iterator;
  35: import java.util.List;
  36: 
  37: /**
  38:  * A class for combining a set of headers.  This class allows for multiple
  39:  * headers with the same name and keeps track of the order in which headers were
  40:  * added.
  41:  * 
  42:  * @author Michael Becke
  43:  * 
  44:  * @since 2.0beta1
  45:  */
  46:	  public class HeaderGroup {
  47:
  48:    /** The list of headers for this group, in the order in which they were added */
  49:    private List headers;
  50:
  51:    /**
  52:     * Constructor for HeaderGroup.
  53:     */
  54:	      public HeaderGroup() {
  55:        this.headers = new ArrayList();
  56:    }
  57:    
  58:    /**
  59:     * Removes any contained headers.
  60:     */
  61:	      public void clear() {
  62:        headers.clear();
  63:    }
  64:    
  65:    /**
  66:     * Adds the given header to the group.  The order in which this header was
  67:     * added is preserved.
  68:     * 
  69:     * @param header the header to add
  70:     */
  71:	      public void addHeader(Header header) {
  72:        headers.add(header);
  73:    }
  74:    
  75:    /**
  76:     * Removes the given header.
  77:     *
  78:     * @param header the header to remove
  79:     */
  80:	      public void removeHeader(Header header) {
  81:        headers.remove(header);
  82:    }
  83:
  84:    /**
  85:     * Sets all of the headers contained within this group overriding any
  86:     * existing headers. The headers are added in the order in which they appear
  87:     * in the array.
  88:     * 
  89:     * @param headers the headers to set
  90:     */
  91:	      public void setHeaders(Header[] headers) {
  92:        clear();
  93:        
  94:	          for (int i = 0; i < headers.length; i++) {
  95:            addHeader(headers[i]);
  96:        }
  97:    }
  98:    
  99:    /**
 100:     * Gets a header representing all of the header values with the given name.
 101:     * If more that one header with the given name exists the values will be
 102:     * combined with a "," as per RFC 2616.
 103:     * 
 104:     * <p>Header name comparison is case insensitive.
 105:     * 
 106:     * @param name the name of the header(s) to get
 107:     * @return a header with a condensed value or <code>null</code> if no
 108:     * headers by the given name are present
 109:     */
 110:	      public Header getCondensedHeader(String name) {
 111:        Header[] headers = getHeaders(name);
 112:        
 113:	          if (headers.length == 0) {
 114:            return null;   
 115:        } else if (headers.length == 1) {
 116:            return new Header(headers[0].getName(), headers[0].getValue());
 117:        } else {
 118:            StringBuffer valueBuffer = new StringBuffer(headers[0].getValue());
 119:            
 120:	              for (int i = 1; i < headers.length; i++) {
 121:                valueBuffer.append(", ");
 122:                valueBuffer.append(headers[i].getValue());
 123:            }
 124:            
 125:            return new Header(name.toLowerCase(), valueBuffer.toString());
 126:        }
 127:    }
 128:    
 129:    /**
 130:     * Gets all of the headers with the given name.  The returned array
 131:     * maintains the relative order in which the headers were added.  
 132:     * 
 133:     * <p>Header name comparison is case insensitive.
 134:     * 
 135:     * @param name the name of the header(s) to get
 136:     * 
 137:     * @return an array of length >= 0
 138:     */
 139:	      public Header[] getHeaders(String name) {
 140:        ArrayList headersFound = new ArrayList();
 141:        
 142:	          for (Iterator headerIter = headers.iterator(); headerIter.hasNext();) {
 143:            Header header = (Header) headerIter.next();
 144:	              if (header.getName().equalsIgnoreCase(name)) {
 145:                headersFound.add(header);
 146:            }
 147:        }
 148:        
 149:        return (Header[]) headersFound.toArray(new Header[headersFound.size()]);
 150:    }
 151:    
 152:    /**
 153:     * Gets the first header with the given name.
 154:     * 
 155:     * <p>Header name comparison is case insensitive.
 156:     * 
 157:     * @param name the name of the header to get
 158:     * @return the first header or <code>null</code>
 159:     */
 160:	      public Header getFirstHeader(String name) {
 161:	          for (Iterator headerIter = headers.iterator(); headerIter.hasNext();) {
 162:            Header header = (Header) headerIter.next();
 163:	              if (header.getName().equalsIgnoreCase(name)) {
 164:                return header;
 165:            }
 166:        }
 167:        
 168:        return null;                
 169:    }
 170:    
 171:    /**
 172:     * Gets the last header with the given name.
 173:     *
 174:     * <p>Header name comparison is case insensitive.
 175:     *
 176:     * @param name the name of the header to get
 177:     * @return the last header or <code>null</code>
 178:     */
 179:	      public Header getLastHeader(String name) {
 180:        // start at the end of the list and work backwards
 181:	          for (int i = headers.size() - 1; i >= 0; i--) {
 182:            Header header = (Header) headers.get(i);
 183:	              if (header.getName().equalsIgnoreCase(name)) {
 184:                return header;
 185:            }            
 186:        }
 187:        
 188:        return null;        
 189:    }
 190:    
 191:    /**
 192:     * Gets all of the headers contained within this group.
 193:     * 
 194:     * @return an array of length >= 0
 195:     */
 196:	      public Header[] getAllHeaders() {
 197:        return (Header[]) headers.toArray(new Header[headers.size()]);
 198:    }
 199:    
 200:    /**
 201:     * Tests if headers with the given name are contained within this group.
 202:     * 
 203:     * <p>Header name comparison is case insensitive.
 204:     * 
 205:     * @param name the header name to test for
 206:     * @return <code>true</code> if at least one header with the name is
 207:     * contained, <code>false</code> otherwise
 208:     */
 209:	      public boolean containsHeader(String name) {
 210:	          for (Iterator headerIter = headers.iterator(); headerIter.hasNext();) {
 211:            Header header = (Header) headerIter.next();
 212:	              if (header.getName().equalsIgnoreCase(name)) {
 213:                return true;
 214:            }
 215:        }
 216:        
 217:        return false;
 218:    }
 219:
 220:    /**
 221:     * Returns an iterator over this group of headers.
 222:     * 
 223:     * @return iterator over this group of headers.
 224:     * 
 225:     * @since 3.0
 226:     */
 227:	      public Iterator getIterator() {
 228:        return this.headers.iterator(); 
 229:    }
 230:}