abstractioservice.java

mina是以Java实现的一个开源的网络程序框架

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 *  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
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 *    http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.mina.core.service;

import java.util.AbstractSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

import org.apache.mina.core.IoUtil;
import org.apache.mina.core.filterchain.DefaultIoFilterChain;
import org.apache.mina.core.filterchain.DefaultIoFilterChainBuilder;
import org.apache.mina.core.filterchain.IoFilterChainBuilder;
import org.apache.mina.core.future.ConnectFuture;
import org.apache.mina.core.future.DefaultIoFuture;
import org.apache.mina.core.future.IoFuture;
import org.apache.mina.core.future.WriteFuture;
import org.apache.mina.core.session.AbstractIoSession;
import org.apache.mina.core.session.DefaultIoSessionDataStructureFactory;
import org.apache.mina.core.session.IdleStatus;
import org.apache.mina.core.session.IoSession;
import org.apache.mina.core.session.IoSessionConfig;
import org.apache.mina.core.session.IoSessionDataStructureFactory;
import org.apache.mina.core.session.IoSessionInitializationException;
import org.apache.mina.core.session.IoSessionInitializer;
import org.apache.mina.util.ExceptionMonitor;
import org.apache.mina.util.NamePreservingRunnable;

/**
 * Base implementation of {@link IoService}s.
 * 
 * An instance of IoService contains an Executor which will handle the incoming
 * events.
 *
 * @author The Apache MINA Project ([e-mail])
 * @version $Rev: 751504 $, $Date: 2009-03-08 20:24:58 +0100 (Sun, 08 Mar 2009) $
 */
public abstract class AbstractIoService implements IoService {
    /** 
     * The unique number identifying the Service. It's incremented
     * for each new IoService created.
     */
    private static final AtomicInteger id = new AtomicInteger();

    /** 
     * The thread name built from the IoService inherited 
     * instance class name and the IoService Id 
     **/
    private final String threadName;

    /**
     * The associated executor, responsible for handling execution of I/O events.
     */
    private final Executor executor;

    /**
     * A flag used to indicate that the local executor has been created
     * inside this instance, and not passed by a caller.
     * 
     * If the executor is locally created, then it will be an instance
     * of the ThreadPoolExecutor class.
     */
    private final boolean createdExecutor;

    /**
     * The IoHandler in charge of managing all the I/O Events. It is 
     */
    private IoHandler handler;

    /**
     * The default {@link IoSessionConfig} which will be used to configure new sessions.
     */
    private final IoSessionConfig sessionConfig;

    private final IoServiceListener serviceActivationListener = new IoServiceListener() {
        public void serviceActivated(IoService service) {
            // Update lastIoTime.
            AbstractIoService s = (AbstractIoService) service;
            IoServiceStatistics _stats = (IoServiceStatistics) s.getStatistics();
            _stats.setLastReadTime(s.getActivationTime());
            _stats.setLastWriteTime(s.getActivationTime());
            _stats.setLastThroughputCalculationTime(s.getActivationTime());

        }

        public void serviceDeactivated(IoService service) {
        }

        public void serviceIdle(IoService service, IdleStatus idleStatus) {
        }

        public void sessionCreated(IoSession session) {
        }

        public void sessionDestroyed(IoSession session) {
        }
    };

    /**
     * Current filter chain builder.
     */
    private IoFilterChainBuilder filterChainBuilder = new DefaultIoFilterChainBuilder();

    private IoSessionDataStructureFactory sessionDataStructureFactory = new DefaultIoSessionDataStructureFactory();

    /**
     * Maintains the {@link IoServiceListener}s of this service.
     */
    private final IoServiceListenerSupport listeners;

    /**
     * A lock object which must be acquired when related resources are
     * destroyed.
     */
    protected final Object disposalLock = new Object();

    private volatile boolean disposing;

    private volatile boolean disposed;

    private IoFuture disposalFuture;

    /**
     * {@inheritDoc}
     */
    private IoServiceStatistics stats = new IoServiceStatistics(this);
    

    /**
     * Constructor for {@link AbstractIoService}. You need to provide a default
     * session configuration and an {@link Executor} for handling I/O events. If
     * a null {@link Executor} is provided, a default one will be created using
     * {@link Executors#newCachedThreadPool()}.
     * 
     * @param sessionConfig
     *            the default configuration for the managed {@link IoSession}
     * @param executor
     *            the {@link Executor} used for handling execution of I/O
     *            events. Can be <code>null</code>.
     */
    protected AbstractIoService(IoSessionConfig sessionConfig, Executor executor) {
        if (sessionConfig == null) {
            throw new NullPointerException("sessionConfig");
        }

        if (getTransportMetadata() == null) {
            throw new NullPointerException("TransportMetadata");
        }

        if (!getTransportMetadata().getSessionConfigType().isAssignableFrom(
                sessionConfig.getClass())) {
            throw new IllegalArgumentException("sessionConfig type: "
                    + sessionConfig.getClass() + " (expected: "
                    + getTransportMetadata().getSessionConfigType() + ")");
        }

        // Create the listeners, and add a first listener : a activation listener
        // for this service, which will give information on the service state.
        listeners = new IoServiceListenerSupport(this);
        listeners.add(serviceActivationListener);

        // Stores the given session configuration
        this.sessionConfig = sessionConfig;

        // Make JVM load the exception monitor before some transports
        // change the thread context class loader.
        ExceptionMonitor.getInstance();

        if (executor == null) {
            this.executor = Executors.newCachedThreadPool();
            createdExecutor = true;
        } else {
            this.executor = executor;
            createdExecutor = false;
        }

        threadName = getClass().getSimpleName() + '-' + id.incrementAndGet();
    }

    /**
     * {@inheritDoc}
     */
    public final IoFilterChainBuilder getFilterChainBuilder() {
        return filterChainBuilder;
    }

    /**
     * {@inheritDoc}
     */
    public final void setFilterChainBuilder(IoFilterChainBuilder builder) {
        if (builder == null) {
            builder = new DefaultIoFilterChainBuilder();
        }
        filterChainBuilder = builder;
    }

    /**
     * {@inheritDoc}
     */
    public final DefaultIoFilterChainBuilder getFilterChain() {
        if (filterChainBuilder instanceof DefaultIoFilterChainBuilder) {
            return (DefaultIoFilterChainBuilder) filterChainBuilder;
        } else {
            throw new IllegalStateException(
                    "Current filter chain builder is not a DefaultIoFilterChainBuilder.");
        }
    }

    /**
     * {@inheritDoc}
     */
    public final void addListener(IoServiceListener listener) {
        listeners.add(listener);
    }

    /**
     * {@inheritDoc}
     */
    public final void removeListener(IoServiceListener listener) {
        listeners.remove(listener);
    }

    /**
     * {@inheritDoc}
     */
    public final boolean isActive() {
        return listeners.isActive();
    }

    /**
     * {@inheritDoc}
     */
    public final boolean isDisposing() {
        return disposing;
    }

    /**
     * {@inheritDoc}
     */
    public final boolean isDisposed() {
        return disposed;
    }

    /**
     * {@inheritDoc}
     */
    public final void dispose() {
        if (disposed) {
            return;