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.HC4.impl.nio.client; import java.io.IOException; import java.util.concurrent.ThreadFactory; import java.util.concurrent.atomic.AtomicReference; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.http.HC4.nio.NHttpClientEventHandler; import org.apache.http.HC4.nio.conn.NHttpClientConnectionManager; import org.apache.http.HC4.nio.reactor.IOEventDispatch; import org.apache.http.HC4.util.Asserts; abstract class CloseableHttpAsyncClientBase extends CloseableHttpPipeliningClient { private final Log log = LogFactory.getLog(getClass()); static enum Status { INACTIVE, ACTIVE, STOPPED } private final NHttpClientConnectionManager connmgr; private final Thread reactorThread; private final AtomicReference<Status> status; public CloseableHttpAsyncClientBase(final NHttpClientConnectionManager connmgr, final ThreadFactory threadFactory, final NHttpClientEventHandler handler) { super(); this.connmgr = connmgr; if (threadFactory != null && handler != null) { this.reactorThread = threadFactory.newThread(new Runnable() { @Override public void run() { try { final IOEventDispatch ioEventDispatch = new InternalIODispatch(handler); connmgr.execute(ioEventDispatch); } catch (final Exception ex) { log.error("I/O reactor terminated abnormally", ex); } finally { status.set(Status.STOPPED); } } }); } else { this.reactorThread = null; } this.status = new AtomicReference<Status>(Status.INACTIVE); } @Override public void start() { if (this.status.compareAndSet(Status.INACTIVE, Status.ACTIVE)) { if (this.reactorThread != null) { this.reactorThread.start(); } } } protected void ensureRunning() { final Status currentStatus = this.status.get(); Asserts.check(currentStatus == Status.ACTIVE, "Request cannot be executed; " + "I/O reactor status: %s", currentStatus); } @Override public void close() { if (this.status.compareAndSet(Status.ACTIVE, Status.STOPPED)) { if (this.reactorThread != null) { try { this.connmgr.shutdown(); } catch (IOException ex) { this.log.error("I/O error shutting down connection manager", ex); } try { this.reactorThread.join(); } catch (final InterruptedException ex) { Thread.currentThread().interrupt(); } } } } @Override public boolean isRunning() { return this.status.get() == Status.ACTIVE; } }