Java tutorial
/* * ==================================================================== * 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.nio.protocol; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import org.apache.http.ConnectionReuseStrategy; import org.apache.http.HttpEntity; import org.apache.http.HttpException; import org.apache.http.HttpRequest; import org.apache.http.HttpResponse; import org.apache.http.nio.ContentDecoder; import org.apache.http.nio.ContentEncoder; import org.apache.http.nio.NHttpClientConnection; import org.apache.http.nio.NHttpClientHandler; import org.apache.http.nio.entity.BufferingNHttpEntity; import org.apache.http.nio.entity.ConsumingNHttpEntity; import org.apache.http.nio.util.ByteBufferAllocator; import org.apache.http.nio.util.HeapByteBufferAllocator; import org.apache.http.params.HttpParams; import org.apache.http.protocol.HttpContext; import org.apache.http.protocol.HttpProcessor; /** * Client protocol handler implementation that provides compatibility with the * blocking I/O by storing the full content of HTTP messages in memory. * The {@link HttpRequestExecutionHandler#handleResponse(HttpResponse, HttpContext)} * method will fire only when the entire message content has been read into a * in-memory buffer. Please note that request execution / response processing * take place the main I/O thread and therefore * {@link HttpRequestExecutionHandler} methods should not block indefinitely. * <p> * When using this protocol handler {@link HttpEntity}'s content can be * generated / consumed using standard {@link InputStream}/{@link OutputStream} * classes. * <p> * IMPORTANT: This protocol handler should be used only when dealing with HTTP * messages that are known to be limited in length. * * * @since 4.0 */ public class BufferingHttpClientHandler implements NHttpClientHandler { private final AsyncNHttpClientHandler asyncHandler; public BufferingHttpClientHandler(final HttpProcessor httpProcessor, final HttpRequestExecutionHandler execHandler, final ConnectionReuseStrategy connStrategy, final ByteBufferAllocator allocator, final HttpParams params) { this.asyncHandler = new AsyncNHttpClientHandler(httpProcessor, new ExecutionHandlerAdaptor(execHandler), connStrategy, allocator, params); } public BufferingHttpClientHandler(final HttpProcessor httpProcessor, final HttpRequestExecutionHandler execHandler, final ConnectionReuseStrategy connStrategy, final HttpParams params) { this(httpProcessor, execHandler, connStrategy, new HeapByteBufferAllocator(), params); } public void setEventListener(final EventListener eventListener) { this.asyncHandler.setEventListener(eventListener); } public void connected(final NHttpClientConnection conn, final Object attachment) { this.asyncHandler.connected(conn, attachment); } public void closed(final NHttpClientConnection conn) { this.asyncHandler.closed(conn); } public void requestReady(final NHttpClientConnection conn) { this.asyncHandler.requestReady(conn); } public void inputReady(final NHttpClientConnection conn, final ContentDecoder decoder) { this.asyncHandler.inputReady(conn, decoder); } public void outputReady(final NHttpClientConnection conn, final ContentEncoder encoder) { this.asyncHandler.outputReady(conn, encoder); } public void responseReceived(final NHttpClientConnection conn) { this.asyncHandler.responseReceived(conn); } public void exception(final NHttpClientConnection conn, final HttpException httpex) { this.asyncHandler.exception(conn, httpex); } public void exception(final NHttpClientConnection conn, final IOException ioex) { this.asyncHandler.exception(conn, ioex); } public void timeout(final NHttpClientConnection conn) { this.asyncHandler.timeout(conn); } static class ExecutionHandlerAdaptor implements NHttpRequestExecutionHandler { private final HttpRequestExecutionHandler execHandler; public ExecutionHandlerAdaptor(final HttpRequestExecutionHandler execHandler) { super(); this.execHandler = execHandler; } public void initalizeContext(final HttpContext context, final Object attachment) { this.execHandler.initalizeContext(context, attachment); } public void finalizeContext(final HttpContext context) { this.execHandler.finalizeContext(context); } public HttpRequest submitRequest(final HttpContext context) { return this.execHandler.submitRequest(context); } public ConsumingNHttpEntity responseEntity(final HttpResponse response, final HttpContext context) throws IOException { return new BufferingNHttpEntity(response.getEntity(), new HeapByteBufferAllocator()); } public void handleResponse(final HttpResponse response, final HttpContext context) throws IOException { this.execHandler.handleResponse(response, context); } } }