Java SocketChannel getConnectedSocketChannel(InetAddress host, int port, int timeout)

Description

This will attempt to connect to the passed host and port.

License

Open Source License

Parameter

Parameter	Description
host	remote host
port	port
timeout	timeout (ms)

Exception

Parameter	Description

Return

SocketChannel object already connected to the remote host/port pair.

Declaration

public static SocketChannel getConnectedSocketChannel(InetAddress host,
        int port, int timeout) throws IOException, InterruptedException 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * This file is part of OpenNMS(R)./*ww  w. j  a va  2s.c  om*/
 *
 * Copyright (C) 2006-2011 The OpenNMS Group, Inc.
 * OpenNMS(R) is Copyright (C) 1999-2011 The OpenNMS Group, Inc.
 *
 * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
 *
 * OpenNMS(R) is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation, either version 3 of the License,
 * or (at your option) any later version.
 *
 * OpenNMS(R) is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with OpenNMS(R).  If not, see:
 *      http://www.gnu.org/licenses/
 *
 * For more information contact:
 *     OpenNMS(R) Licensing <license@opennms.org>
 *     http://www.opennms.org/
 *     http://www.opennms.com/
 *******************************************************************************/

import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.nio.channels.SocketChannel;

public class Main {
    /**
     * This will attempt to connect to the passed host and port. The connection
     * will be made in non-blocking mode, so if there is no route to the host,
     * then it won't hold up capsd or the poller.
     *
     * Once a connection is made, the channel is returned to blocking mode.
     *
     * @param host
     *            remote host
     * @param port
     *            port
     * @param timeout
     *            timeout (ms)
     * @return SocketChannel object already connected to the remote host/port
     *         pair.
     * @throws java.io.IOException if any.
     * @throws java.lang.InterruptedException if any.
     */
    public static SocketChannel getConnectedSocketChannel(InetAddress host,
            int port, int timeout) throws IOException, InterruptedException {
        SocketChannel sChannel = null;

        try {
            // try to connect first as non-blocking
            sChannel = SocketChannel.open();
            sChannel.configureBlocking(false);
            sChannel.connect(new InetSocketAddress(host, port));
            long startConnectTime = System.currentTimeMillis();

            // see if connected
            do {
                if (!sChannel.finishConnect()) {
                    Thread.sleep(100);
                }
            } while (!sChannel.isConnected()
                    && (System.currentTimeMillis() - startConnectTime) <= timeout);

            // check timeout
            if (!sChannel.isConnected()) {
                if (sChannel.socket() != null)
                    sChannel.socket().close();

                sChannel.close();
                sChannel = null;
            } else {
                // we're connected, so return channel to blocking mode. Avoids
                // No Route to Host errors.
                sChannel.configureBlocking(true);
                sChannel.socket().setSoTimeout(timeout);
            }
        } catch (IOException e) {
            if (sChannel != null) {
                if (sChannel.socket() != null)
                    sChannel.socket().close();
                sChannel.close();
                sChannel = null;
            }
            throw e;
        } catch (InterruptedException e) {
            if (sChannel != null) {
                if (sChannel.socket() != null)
                    sChannel.socket().close();
                sChannel.close();
                sChannel = null;
            }
            throw e;
        }

        return sChannel;
    }
}

Related

1. createServerSocketChannel(int aPort, String aHostname)
2. enhanceExceptionWithAddress(final SocketChannel channel, final IOException e)
3. finishConnect(SocketChannel socketChannel)
4. getSocketAddress(SocketChannel socketChannel)
5. getSocketDisplayString(SocketChannel channel)
6. openSocketChannel(SocketAddress sa)
7. pingWithSocketChannel()