1   /*
    2    * $HeadURL: https://svn.apache.org/repos/asf/httpcomponents/httpcore/tags/4.0.1/httpcore/src/main/java/org/apache/http/protocol/RequestContent.java $
    3    * $Revision: 744532 $
    4    * $Date: 2009-02-14 18:12:18 +0100 (Sat, 14 Feb 2009) $
    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   
   32   package org.apache.http.protocol;
   33   
   34   import java.io.IOException;
   35   
   36   import org.apache.http.HttpEntity;
   37   import org.apache.http.HttpEntityEnclosingRequest;
   38   import org.apache.http.HttpException;
   39   import org.apache.http.HttpRequest;
   40   import org.apache.http.HttpRequestInterceptor;
   41   import org.apache.http.HttpVersion;
   42   import org.apache.http.ProtocolVersion;
   43   import org.apache.http.ProtocolException;
   44   
   45   /**
   46    * RequestContent is the most important interceptor for outgoing requests. 
   47    * It is responsible for delimiting content length by adding 
   48    * <code>Content-Length</code> or <code>Transfer-Content</code> headers based 
   49    * on the properties of the enclosed entity and the protocol version. 
   50    * This interceptor is required for correct functioning of client side protocol 
   51    * processors.
   52   
   53    *
   54    * @version $Revision: 744532 $
   55    * 
   56    * @since 4.0
   57    */
   58   public class RequestContent implements HttpRequestInterceptor {
   59   
   60       public RequestContent() {
   61           super();
   62       }
   63       
   64       public void process(final HttpRequest request, final HttpContext context) 
   65               throws HttpException, IOException {
   66           if (request == null) {
   67               throw new IllegalArgumentException("HTTP request may not be null");
   68           }
   69           if (request instanceof HttpEntityEnclosingRequest) {
   70               if (request.containsHeader(HTTP.TRANSFER_ENCODING)) {
   71                   throw new ProtocolException("Transfer-encoding header already present");
   72               }
   73               if (request.containsHeader(HTTP.CONTENT_LEN)) {
   74                   throw new ProtocolException("Content-Length header already present");
   75               }
   76               ProtocolVersion ver = request.getRequestLine().getProtocolVersion();
   77               HttpEntity entity = ((HttpEntityEnclosingRequest)request).getEntity();
   78               if (entity == null) {
   79                   request.addHeader(HTTP.CONTENT_LEN, "0");
   80                   return;
   81               }
   82               // Must specify a transfer encoding or a content length 
   83               if (entity.isChunked() || entity.getContentLength() < 0) {
   84                   if (ver.lessEquals(HttpVersion.HTTP_1_0)) {
   85                       throw new ProtocolException(
   86                               "Chunked transfer encoding not allowed for " + ver);
   87                   }
   88                   request.addHeader(HTTP.TRANSFER_ENCODING, HTTP.CHUNK_CODING);
   89               } else {
   90                   request.addHeader(HTTP.CONTENT_LEN, Long.toString(entity.getContentLength()));
   91               }
   92               // Specify a content type if known
   93               if (entity.getContentType() != null && !request.containsHeader(
   94                       HTTP.CONTENT_TYPE )) {
   95                   request.addHeader(entity.getContentType()); 
   96               }
   97               // Specify a content encoding if known
   98               if (entity.getContentEncoding() != null && !request.containsHeader(
   99                       HTTP.CONTENT_ENCODING)) {
  100                   request.addHeader(entity.getContentEncoding()); 
  101               }
  102           }
  103       }
  104       
  105   }