1   /*
    2    * $HeadURL: https://svn.apache.org/repos/asf/jakarta/httpcomponents/httpcore/tags/4.0-alpha2/src/java/org/apache/http/protocol/HttpExecutionContext.java $
    3    * $Revision: 376961 $
    4    * $Date: 2006-02-11 11:32:50 +0100 (Sat, 11 Feb 2006) $
    5    *
    6    * ====================================================================
    7    *
    8    *  Copyright 1999-2006 The Apache Software Foundation
    9    *
   10    *  Licensed under the Apache License, Version 2.0 (the "License");
   11    *  you may not use this file except in compliance with the License.
   12    *  You may obtain a copy of the License at
   13    *
   14    *      http://www.apache.org/licenses/LICENSE-2.0
   15    *
   16    *  Unless required by applicable law or agreed to in writing, software
   17    *  distributed under the License is distributed on an "AS IS" BASIS,
   18    *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   19    *  See the License for the specific language governing permissions and
   20    *  limitations under the License.
   21    * ====================================================================
   22    *
   23    * This software consists of voluntary contributions made by many
   24    * individuals on behalf of the Apache Software Foundation.  For more
   25    * information on the Apache Software Foundation, please see
   26    * <http://www.apache.org/>.
   27    *
   28    */
   29   
   30   package org.apache.http.protocol;
   31   
   32   import java.util.HashMap;
   33   import java.util.Map;
   34   
   35   
   36   /**
   37    * Default implementation of the {@link HttpContext HttpContext}.
   38    *
   39    * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
   40    *
   41    * @version $Revision: 376961 $
   42    * 
   43    * @since 4.0
   44    */
   45   public class HttpExecutionContext implements HttpContext {
   46       
   47       public static final String HTTP_TARGET_HOST = "http.target_host"; 
   48       public static final String HTTP_PROXY_HOST  = "http.proxy_host"; 
   49       public static final String HTTP_REQ_SENT    = "http.request_sent"; 
   50       
   51       private final HttpContext parentContext;
   52       private Map map = null;
   53       
   54       public HttpExecutionContext(final HttpContext parentContext) {
   55           super();
   56           this.parentContext = parentContext;
   57       }
   58       
   59       public Object getAttribute(final String id) {
   60           if (id == null) {
   61               throw new IllegalArgumentException("Id may not be null");
   62           }
   63           Object obj = null;
   64           if (this.map != null) {
   65               obj = this.map.get(id);
   66           }
   67           if (obj == null && this.parentContext != null) {
   68               obj = this.parentContext.getAttribute(id);
   69           }
   70           return obj;
   71       }
   72   
   73       public void setAttribute(final String id, final Object obj) {
   74           if (id == null) {
   75               throw new IllegalArgumentException("Id may not be null");
   76           }
   77           if (this.map == null) {
   78               this.map = new HashMap();
   79           }
   80           this.map.put(id, obj);
   81       }
   82       
   83       public Object removeAttribute(final String id) {
   84           if (id == null) {
   85               throw new IllegalArgumentException("Id may not be null");
   86           }
   87           if (this.map != null) {
   88               return this.map.remove(id);
   89           } else {
   90               return null;
   91           }
   92       }
   93   
   94   }