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.client.methods; import java.io.IOException; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; import org.apache.http.HttpRequest; import org.apache.http.client.utils.CloneUtils; import org.apache.http.concurrent.Cancellable; import org.apache.http.conn.ClientConnectionRequest; import org.apache.http.conn.ConnectionReleaseTrigger; import org.apache.http.message.AbstractHttpMessage; @SuppressWarnings("deprecation") public abstract class AbstractExecutionAwareRequest extends AbstractHttpMessage implements HttpExecutionAware, AbortableHttpRequest, Cloneable, HttpRequest { private Lock abortLock; private volatile boolean aborted; private volatile Cancellable cancellable; protected AbstractExecutionAwareRequest() { super(); this.abortLock = new ReentrantLock(); } @Deprecated public void setConnectionRequest(final ClientConnectionRequest connRequest) { if (this.aborted) { return; } this.abortLock.lock(); try { this.cancellable = new Cancellable() { public boolean cancel() { connRequest.abortRequest(); return true; } }; } finally { this.abortLock.unlock(); } } @Deprecated public void setReleaseTrigger(final ConnectionReleaseTrigger releaseTrigger) { if (this.aborted) { return; } this.abortLock.lock(); try { this.cancellable = new Cancellable() { public boolean cancel() { try { releaseTrigger.abortConnection(); return true; } catch (final IOException ex) { return false; } } }; } finally { this.abortLock.unlock(); } } private void cancelExecution() { if (this.cancellable != null) { this.cancellable.cancel(); this.cancellable = null; } } public void abort() { if (this.aborted) { return; } this.abortLock.lock(); try { this.aborted = true; cancelExecution(); } finally { this.abortLock.unlock(); } } public boolean isAborted() { return this.aborted; } /** * @since 4.2 */ public void setCancellable(final Cancellable cancellable) { if (this.aborted) { return; } this.abortLock.lock(); try { this.cancellable = cancellable; } finally { this.abortLock.unlock(); } } @Override public Object clone() throws CloneNotSupportedException { final AbstractExecutionAwareRequest clone = (AbstractExecutionAwareRequest) super.clone(); clone.headergroup = CloneUtils.cloneObject(this.headergroup); clone.params = CloneUtils.cloneObject(this.params); clone.abortLock = new ReentrantLock(); clone.cancellable = null; clone.aborted = false; return clone; } /** * @since 4.2 */ public void completed() { this.abortLock.lock(); try { this.cancellable = null; } finally { this.abortLock.unlock(); } } /** * Resets internal state of the request making it reusable. * * @since 4.2 */ public void reset() { this.abortLock.lock(); try { cancelExecution(); this.aborted = false; } finally { this.abortLock.unlock(); } } }