poke.monitor.ResourceMonitor.java Source code

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Here is the source code for poke.monitor.ResourceMonitor.java

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/*
 * copyright 2014, gash
 * 
 * Gash 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.
 */
package poke.monitor;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import poke.server.ServerInitializer;
import eye.Comm.Request;

/**
     
 * 
 * @author gash
 * 
 */
public class ResourceMonitor {
    protected static Logger logger = LoggerFactory.getLogger("mgmt");

    protected ChannelFuture channel; // do not use directly, call connect()!
    private EventLoopGroup group;

    private String host;
    private int port;

    public ResourceMonitor(String host, String port) {
        this.host = host;
        this.port = Integer.parseInt(port);
        this.group = new NioEventLoopGroup();
    }

    public ResourceMonitor(String host, int port) {
        this.host = host;
        this.port = port;
        this.group = new NioEventLoopGroup();
    }

    /**
     * create connection to remote server
     * 
     * @return
     */
    public Channel connect() {
        // Start the connection attempt.
        if (channel == null) {
            try {

                Bootstrap b = new Bootstrap();
                // @TODO newFixedThreadPool(2);
                b.group(group).channel(NioSocketChannel.class).handler(new ServerInitializer(false));
                b.option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10000);
                b.option(ChannelOption.TCP_NODELAY, true);
                b.option(ChannelOption.SO_KEEPALIVE, true);

                // Make the connection attempt.
                logger.info(host + ":" + port + "IN Resource monitor");
                channel = b.connect(host, port).syncUninterruptibly();
                channel.awaitUninterruptibly(5000l);

            } catch (Exception ex) {
                logger.debug("failed to initialize the heartbeat connection");

            }
        }

        if (channel != null && channel.isDone() && channel.isSuccess()) {

            logger.info("Channel is Created" + channel);
            return channel.channel();
        } else {
            logger.info("In Error from Establish Connection");
            throw new RuntimeException("Not able to establish connection to server");
        }

    }

    //}
    public boolean isConnected() {
        if (channel == null)
            return false;
        else
            return channel.channel().isOpen();
    }

    public String getNodeInfo() {
        if (host != null)
            return host + ":" + port;
        else
            return "Unknown";
    }

    /**
     * request the node to send heartbeats.
     * @param management 
     * 
     * @return did a connect and message succeed
     */
    public boolean startFindLeader(Request request) {

        boolean rtn = false;
        try {
            Channel ch = connect();
            ch.writeAndFlush(request);
            rtn = true;
        } catch (Exception e) {
            logger.error("could not send connect to node", e);
        }
        return rtn;
    }

    public void waitForever() {
        try {
            boolean connected = true;
            while (connected) {
                Thread.sleep(2000);
            }
            logger.info("---> trying to connect external Node");
        } catch (Exception e) {
            // e.printStackTrace();
        }
    }

    //Method to start voting
    public void startVoting(Request request) {
        boolean rtn = false;
        try {
            Channel ch = connect();
            ch.writeAndFlush(request);
            rtn = true;
        } catch (Exception e) {
            logger.error("could not send connect to node", e);
        }

    }

}