| /* |
| * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/protocol/HttpRequestExecutor.java $ |
| * $Revision: 576073 $ |
| * $Date: 2007-09-16 03:53:13 -0700 (Sun, 16 Sep 2007) $ |
| * |
| * ==================================================================== |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| * |
| */ |
| |
| package org.apache.http.protocol; |
| |
| import java.io.IOException; |
| import java.net.ProtocolException; |
| |
| import org.apache.http.HttpClientConnection; |
| import org.apache.http.HttpEntityEnclosingRequest; |
| import org.apache.http.HttpException; |
| import org.apache.http.HttpRequest; |
| import org.apache.http.HttpResponse; |
| import org.apache.http.HttpStatus; |
| import org.apache.http.HttpVersion; |
| import org.apache.http.ProtocolVersion; |
| import org.apache.http.params.CoreProtocolPNames; |
| |
| /** |
| * Sends HTTP requests and receives the responses. |
| * Takes care of request preprocessing and response postprocessing |
| * by the respective interceptors. |
| * |
| * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a> |
| * |
| * @version $Revision: 576073 $ |
| * |
| * @since 4.0 |
| */ |
| public class HttpRequestExecutor { |
| |
| /** |
| * Create a new request executor. |
| */ |
| public HttpRequestExecutor() { |
| super(); |
| } |
| |
| /** |
| * Decide whether a response comes with an entity. |
| * The implementation in this class is based on RFC 2616. |
| * Unknown methods and response codes are supposed to |
| * indicate responses with an entity. |
| * <br/> |
| * Derived executors can override this method to handle |
| * methods and response codes not specified in RFC 2616. |
| * |
| * @param request the request, to obtain the executed method |
| * @param response the response, to obtain the status code |
| */ |
| protected boolean canResponseHaveBody(final HttpRequest request, |
| final HttpResponse response) { |
| |
| if ("HEAD".equalsIgnoreCase(request.getRequestLine().getMethod())) { |
| return false; |
| } |
| int status = response.getStatusLine().getStatusCode(); |
| return status >= HttpStatus.SC_OK |
| && status != HttpStatus.SC_NO_CONTENT |
| && status != HttpStatus.SC_NOT_MODIFIED |
| && status != HttpStatus.SC_RESET_CONTENT; |
| } |
| |
| /** |
| * Synchronously send a request and obtain the response. |
| * |
| * @param request the request to send. It will be preprocessed. |
| * @param conn the open connection over which to send |
| * |
| * @return the response to the request, postprocessed |
| * |
| * @throws HttpException in case of a protocol or processing problem |
| * @throws IOException in case of an I/O problem |
| */ |
| public HttpResponse execute( |
| final HttpRequest request, |
| final HttpClientConnection conn, |
| final HttpContext context) |
| throws IOException, HttpException { |
| if (request == null) { |
| throw new IllegalArgumentException("HTTP request may not be null"); |
| } |
| if (conn == null) { |
| throw new IllegalArgumentException("Client connection may not be null"); |
| } |
| if (context == null) { |
| throw new IllegalArgumentException("HTTP context may not be null"); |
| } |
| |
| try { |
| HttpResponse response = doSendRequest(request, conn, context); |
| if (response == null) { |
| response = doReceiveResponse(request, conn, context); |
| } |
| return response; |
| } catch (IOException ex) { |
| conn.close(); |
| throw ex; |
| } catch (HttpException ex) { |
| conn.close(); |
| throw ex; |
| } catch (RuntimeException ex) { |
| conn.close(); |
| throw ex; |
| } |
| } |
| |
| /** |
| * Prepare a request for sending. |
| * |
| * @param request the request to prepare |
| * @param processor the processor to use |
| * @param context the context for sending the request |
| * |
| * @throws HttpException in case of a protocol or processing problem |
| * @throws IOException in case of an I/O problem |
| */ |
| public void preProcess( |
| final HttpRequest request, |
| final HttpProcessor processor, |
| final HttpContext context) |
| throws HttpException, IOException { |
| if (request == null) { |
| throw new IllegalArgumentException("HTTP request may not be null"); |
| } |
| if (processor == null) { |
| throw new IllegalArgumentException("HTTP processor may not be null"); |
| } |
| if (context == null) { |
| throw new IllegalArgumentException("HTTP context may not be null"); |
| } |
| processor.process(request, context); |
| } |
| |
| /** |
| * Send a request over a connection. |
| * This method also handles the expect-continue handshake if necessary. |
| * If it does not have to handle an expect-continue handshake, it will |
| * not use the connection for reading or anything else that depends on |
| * data coming in over the connection. |
| * |
| * @param request the request to send, already |
| * {@link #preProcess preprocessed} |
| * @param conn the connection over which to send the request, |
| * already established |
| * @param context the context for sending the request |
| * |
| * @return a terminal response received as part of an expect-continue |
| * handshake, or |
| * <code>null</code> if the expect-continue handshake is not used |
| * |
| * @throws HttpException in case of a protocol or processing problem |
| * @throws IOException in case of an I/O problem |
| */ |
| protected HttpResponse doSendRequest( |
| final HttpRequest request, |
| final HttpClientConnection conn, |
| final HttpContext context) |
| throws IOException, HttpException { |
| if (request == null) { |
| throw new IllegalArgumentException("HTTP request may not be null"); |
| } |
| if (conn == null) { |
| throw new IllegalArgumentException("HTTP connection may not be null"); |
| } |
| if (context == null) { |
| throw new IllegalArgumentException("HTTP context may not be null"); |
| } |
| |
| HttpResponse response = null; |
| context.setAttribute(ExecutionContext.HTTP_REQ_SENT, Boolean.FALSE); |
| |
| conn.sendRequestHeader(request); |
| if (request instanceof HttpEntityEnclosingRequest) { |
| // Check for expect-continue handshake. We have to flush the |
| // headers and wait for an 100-continue response to handle it. |
| // If we get a different response, we must not send the entity. |
| boolean sendentity = true; |
| final ProtocolVersion ver = |
| request.getRequestLine().getProtocolVersion(); |
| if (((HttpEntityEnclosingRequest) request).expectContinue() && |
| !ver.lessEquals(HttpVersion.HTTP_1_0)) { |
| |
| conn.flush(); |
| // As suggested by RFC 2616 section 8.2.3, we don't wait for a |
| // 100-continue response forever. On timeout, send the entity. |
| int tms = request.getParams().getIntParameter( |
| CoreProtocolPNames.WAIT_FOR_CONTINUE, 2000); |
| |
| if (conn.isResponseAvailable(tms)) { |
| response = conn.receiveResponseHeader(); |
| if (canResponseHaveBody(request, response)) { |
| conn.receiveResponseEntity(response); |
| } |
| int status = response.getStatusLine().getStatusCode(); |
| if (status < 200) { |
| if (status != HttpStatus.SC_CONTINUE) { |
| throw new ProtocolException( |
| "Unexpected response: " + response.getStatusLine()); |
| } |
| // discard 100-continue |
| response = null; |
| } else { |
| sendentity = false; |
| } |
| } |
| } |
| if (sendentity) { |
| conn.sendRequestEntity((HttpEntityEnclosingRequest) request); |
| } |
| } |
| conn.flush(); |
| context.setAttribute(ExecutionContext.HTTP_REQ_SENT, Boolean.TRUE); |
| return response; |
| } |
| |
| /** |
| * Wait for and receive a response. |
| * This method will automatically ignore intermediate responses |
| * with status code 1xx. |
| * |
| * @param request the request for which to obtain the response |
| * @param conn the connection over which the request was sent |
| * @param context the context for receiving the response |
| * |
| * @return the final response, not yet post-processed |
| * |
| * @throws HttpException in case of a protocol or processing problem |
| * @throws IOException in case of an I/O problem |
| */ |
| protected HttpResponse doReceiveResponse( |
| final HttpRequest request, |
| final HttpClientConnection conn, |
| final HttpContext context) |
| throws HttpException, IOException { |
| if (request == null) { |
| throw new IllegalArgumentException("HTTP request may not be null"); |
| } |
| if (conn == null) { |
| throw new IllegalArgumentException("HTTP connection may not be null"); |
| } |
| if (context == null) { |
| throw new IllegalArgumentException("HTTP context may not be null"); |
| } |
| |
| HttpResponse response = null; |
| int statuscode = 0; |
| |
| while (response == null || statuscode < HttpStatus.SC_OK) { |
| |
| response = conn.receiveResponseHeader(); |
| if (canResponseHaveBody(request, response)) { |
| conn.receiveResponseEntity(response); |
| } |
| statuscode = response.getStatusLine().getStatusCode(); |
| |
| } // while intermediate response |
| |
| return response; |
| |
| } |
| |
| /** |
| * Finish a response. |
| * This includes post-processing of the response object. |
| * It does <i>not</i> read the response entity, if any. |
| * It does <i>not</i> allow for immediate re-use of the |
| * connection over which the response is coming in. |
| * |
| * @param response the response object to finish |
| * @param processor the processor to use |
| * @param context the context for post-processing the response |
| * |
| * @throws HttpException in case of a protocol or processing problem |
| * @throws IOException in case of an I/O problem |
| */ |
| public void postProcess( |
| final HttpResponse response, |
| final HttpProcessor processor, |
| final HttpContext context) |
| throws HttpException, IOException { |
| if (response == null) { |
| throw new IllegalArgumentException("HTTP response may not be null"); |
| } |
| if (processor == null) { |
| throw new IllegalArgumentException("HTTP processor may not be null"); |
| } |
| if (context == null) { |
| throw new IllegalArgumentException("HTTP context may not be null"); |
| } |
| processor.process(response, context); |
| } |
| |
| } // class HttpRequestExecutor |