org.ros.internal.transport.tcp.TcpClientConnectionManager.java Source code

Introduction

Here is the source code for org.ros.internal.transport.tcp.TcpClientConnectionManager.java

Source

/*
 * Copyright (C) 2011 Google Inc.
 * 
 * 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 org.ros.internal.transport.tcp;

import java.net.SocketAddress;
import java.nio.ByteOrder;
import java.util.Collection;
import java.util.concurrent.ScheduledExecutorService;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jboss.netty.buffer.ChannelBufferFactory;
import org.jboss.netty.buffer.HeapChannelBufferFactory;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFactory;
import org.jboss.netty.channel.ChannelHandler;
import org.jboss.netty.channel.group.ChannelGroup;
import org.jboss.netty.channel.group.DefaultChannelGroup;
import org.jboss.netty.channel.socket.nio.NioClientSocketChannelFactory;

import com.google.common.collect.Lists;

/**
 * Manage TCP connections for subscribers and service clients.
 * 
 * @author damonkohler@google.com (Damon Kohler)
 */
public class TcpClientConnectionManager {

    private static final boolean DEBUG = false;
    private static final Log log = LogFactory.getLog(TcpClientConnectionManager.class);

    private final ChannelFactory channelFactory;
    private final ChannelGroup channelGroup;
    private final ChannelBufferFactory channelBufferFactory;
    private final Collection<TcpClientConnection> tcpClientConnections;
    private final ScheduledExecutorService executorService;

    public TcpClientConnectionManager(ScheduledExecutorService executorService) {
        this.executorService = executorService;
        channelFactory = new NioClientSocketChannelFactory(executorService, executorService);
        channelGroup = new DefaultChannelGroup();
        channelBufferFactory = new HeapChannelBufferFactory(ByteOrder.LITTLE_ENDIAN);
        tcpClientConnections = Lists.newArrayList();
    }

    /**
     * Connects to a server.
     * 
     * <p>
     * This call blocks until the connection is established or fails.
     * 
     * @param connectionName
     * @param address
     * @param handler
     * @param handlerName
     * @return a new {@link TcpClientConnection}
     */
    public TcpClientConnection connect(String connectionName, SocketAddress address,
            TcpClientConnectionListener listener, ChannelHandler handler, String handlerName) {
        TcpClientConnection connection = new TcpClientConnection(this, connectionName, address, listener,
                channelFactory, channelBufferFactory, channelGroup, executorService, log);
        connection.connect(address, handler, handlerName);

        // Will only get stored if the connection happen
        tcpClientConnections.add(connection);

        return connection;
    }

    /**
     * Sets all {@link TcpClientConnection}s as non-persistent and closes all
     * open {@link Channel}s.
     */
    public void shutdown() {
        for (TcpClientConnection tcpClientConnection : tcpClientConnections) {
            tcpClientConnection.setPersistent(false);
            tcpClientConnection.clear();
        }
        channelGroup.close().awaitUninterruptibly();
        tcpClientConnections.clear();
        // Not calling channelFactory.releaseExternalResources() or
        // bootstrap.releaseExternalResources() since only external resources
        // are
        // the ExecutorService and control of that must remain with the overall
        // application.
    }

    /**
     * Unregister a connection from the manager.
     * 
     * @param connection
     *            the connection to remove
     */
    public void unregisterConnection(TcpClientConnection connection) {
        tcpClientConnections.remove(connection);
    }
}