com.asuraiv.coordination.Worker.java Source code

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Here is the source code for com.asuraiv.coordination.Worker.java

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/*
 * @(#)Worker.java $version 2016. 1. 4.
 *
 * Copyright 2007 NHN Corp. All rights Reserved. 
 * NHN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package com.asuraiv.coordination;

import java.io.IOException;
import java.util.List;

import org.apache.zookeeper.AsyncCallback;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.KeeperException.Code;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.asuraiv.coordination.enums.TaskStatus;
import com.asuraiv.coordination.enums.WorkerStatus;
import com.asuraiv.coordination.util.ZooKeeperUtils;

/**
 * @author Jupyo Hong
 */
public class Worker implements Runnable, Watcher, AsyncCallback.ChildrenCallback {

    private static final Logger LOG = LoggerFactory.getLogger(Worker.class);

    private ZooKeeperUtils zkUtils;

    private String workerName;

    private StringCallback createZNodeCallback = new StringCallback() {

        public void processResult(int rc, String path, Object ctx, String name) {

            switch (Code.get(rc)) {
            case CONNECTIONLOSS:
                createWorkerZNode((byte[]) ctx);
                break;
            case OK:
                workerName = name.substring(name.lastIndexOf("/") + 1);
                // Log 
                break;
            case NODEEXISTS:
                // Log 
                break;
            default:
                // Log 
                break;
            }
        }
    };

    /**
     * @param hostPort
     * @throws IOException 
     */
    public Worker(String hostPort) throws IOException {
        zkUtils = new ZooKeeperUtils(new ZooKeeper(hostPort, 15000, this));
    }

    /**
     * 
     * @param event
     * @see org.apache.zookeeper.Watcher#process(org.apache.zookeeper.WatchedEvent)
     */
    public void process(WatchedEvent event) {
        zkUtils.asyncGetChildren("/assign", true, /* AsyncCallback.ChildrenCallback */this, null);
    }

    /**
     * @param rc
     * @param path
     * @param ctx
     * @param children
     * @see org.apache.zookeeper.AsyncCallback.ChildrenCallback#processResult(int, java.lang.String, java.lang.Object, java.util.List)
     */
    public void processResult(int rc, String path, Object ctx, List<String> childrenOfAssignNode) {
        LOG.info("[WORKER] {}  ??  ...", workerName);
        for (String child : childrenOfAssignNode) {
            // ?? ?? 
            if (child.equals(workerName)) {
                doTasksProcess();
            }
        }
    }

    /**
     * ? !
     */
    private void doTasksProcess() {

        String task = zkUtils.getData("/assign/" + workerName);
        // task ? RUNNING  
        zkUtils.setData("/tasks/" + task, TaskStatus.RUNNING.name());
        // worker ?? ?? Busy 
        zkUtils.setData("/workers/" + workerName, WorkerStatus.BUSY.toString());

        for (int i = 0; i < 10; i++) {
            LOG.info("[WORKER][{}] '{}' ??  ...", workerName, task);
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
            }
        }
        LOG.info("[WORKER][{}] '{}' ?? ??!", workerName, task);

        // task  ?? ? DONE 
        zkUtils.setData("/tasks/" + task, TaskStatus.DONE.name());
        //  worker ?? ? Idle 
        zkUtils.setData("/workers/" + workerName, WorkerStatus.IDLE.name());
        // assign ? ? task 
        zkUtils.delete("/assign/" + workerName);
    }

    /**
     * @see java.lang.Runnable#run()
     */
    public void run() {

        // worker  ?
        String status = WorkerStatus.IDLE.name();
        createWorkerZNode(status.getBytes());

        zkUtils.asyncGetChildren("/assign", true, /* AsyncCallback.ChildrenCallback */this, null);

        try {
            synchronized (this) {
                while (true) {
                    wait();
                }
            }
        } catch (InterruptedException e) {
        }
    }

    /**
     * @param data
     * @throws KeeperException
     * @throws InterruptedException
     */
    private void createWorkerZNode(byte[] data) {
        zkUtils.asyncCreate("/workers/worker-", data, Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL_SEQUENTIAL,
                createZNodeCallback, null);
    }
}