Java tutorial
/* * Copyright 2002-2010 the original author or authors. * * Licensed 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. */ package jails.http.client; import jails.http.HttpMethod; import java.io.IOException; import java.net.URI; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.HttpConnectionManager; import org.apache.commons.httpclient.HttpMethodBase; import org.apache.commons.httpclient.MultiThreadedHttpConnectionManager; import org.apache.commons.httpclient.methods.DeleteMethod; import org.apache.commons.httpclient.methods.GetMethod; import org.apache.commons.httpclient.methods.HeadMethod; import org.apache.commons.httpclient.methods.OptionsMethod; import org.apache.commons.httpclient.methods.PostMethod; import org.apache.commons.httpclient.methods.PutMethod; import org.apache.commons.httpclient.methods.TraceMethod; import org.springframework.beans.factory.DisposableBean; import org.springframework.util.Assert; /** * {@link jails.http.client.ClientHttpRequestFactory} implementation that uses * <a href="http://jakarta.apache.org/commons/httpclient">Jakarta Commons HttpClient</a> to create requests. * * <p>Allows to use a pre-configured {@link HttpClient} instance - * potentially with authentication, HTTP connection pooling, etc. * * @author Arjen Poutsma * @since 3.0 * @see jails.http.client.SimpleClientHttpRequestFactory */ public class CommonsClientHttpRequestFactory implements ClientHttpRequestFactory, DisposableBean { private static final int DEFAULT_READ_TIMEOUT_MILLISECONDS = (60 * 1000); private HttpClient httpClient; /** * Create a new instance of the <code>CommonsHttpRequestFactory</code> with a default * {@link HttpClient} that uses a default {@link MultiThreadedHttpConnectionManager}. */ public CommonsClientHttpRequestFactory() { httpClient = new HttpClient(new MultiThreadedHttpConnectionManager()); this.setReadTimeout(DEFAULT_READ_TIMEOUT_MILLISECONDS); } /** * Create a new instance of the <code>CommonsHttpRequestFactory</code> with the given * {@link HttpClient} instance. * @param httpClient the HttpClient instance to use for this factory */ public CommonsClientHttpRequestFactory(HttpClient httpClient) { Assert.notNull(httpClient, "httpClient must not be null"); this.httpClient = httpClient; } /** * Set the <code>HttpClient</code> used by this factory. */ public void setHttpClient(HttpClient httpClient) { this.httpClient = httpClient; } /** * Return the <code>HttpClient</code> used by this factory. */ public HttpClient getHttpClient() { return this.httpClient; } /** * Set the socket read timeout for the underlying HttpClient. A value of 0 means <em>never</em> timeout. * @param timeout the timeout value in milliseconds * @see org.apache.commons.httpclient.params.HttpConnectionManagerParams#setSoTimeout(int) */ public void setReadTimeout(int timeout) { if (timeout < 0) { throw new IllegalArgumentException("timeout must be a non-negative value"); } getHttpClient().getHttpConnectionManager().getParams().setSoTimeout(timeout); } public ClientHttpRequest createRequest(URI uri, HttpMethod httpMethod) throws IOException { HttpMethodBase commonsHttpMethod = createCommonsHttpMethod(httpMethod, uri.toString()); postProcessCommonsHttpMethod(commonsHttpMethod); return new CommonsClientHttpRequest(getHttpClient(), commonsHttpMethod); } /** * Create a Commons HttpMethodBase object for the given HTTP method * and URI specification. * @param httpMethod the HTTP method * @param uri the URI * @return the Commons HttpMethodBase object */ protected HttpMethodBase createCommonsHttpMethod(HttpMethod httpMethod, String uri) { switch (httpMethod) { case GET: return new GetMethod(uri); case DELETE: return new DeleteMethod(uri); case HEAD: return new HeadMethod(uri); case OPTIONS: return new OptionsMethod(uri); case POST: return new PostMethod(uri); case PUT: return new PutMethod(uri); case TRACE: return new TraceMethod(uri); default: throw new IllegalArgumentException("Invalid HTTP method: " + httpMethod); } } /** * Template method that allows for manipulating the {@link org.apache.commons.httpclient.HttpMethodBase} * before it is returned as part of a {@link CommonsClientHttpRequest}. * <p>The default implementation is empty. * @param httpMethod the Commons HTTP method object to process */ protected void postProcessCommonsHttpMethod(HttpMethodBase httpMethod) { } /** * Shutdown hook that closes the underlying {@link HttpConnectionManager}'s * connection pool, if any. */ public void destroy() { HttpConnectionManager connectionManager = getHttpClient().getHttpConnectionManager(); if (connectionManager instanceof MultiThreadedHttpConnectionManager) { ((MultiThreadedHttpConnectionManager) connectionManager).shutdown(); } } }