基于zookeeper集群实现分布式FIFO队列的工程实践

上一篇基于zk集群实现了分布式的id生成器，本篇继续基于zk集群进行场景实践，分布式的FIFO队列怎么用zk去做呢？直接上代码。

一、创建队列需要用到的bean

package com.coderman.zookeeper.clusterdemo.queuefifodemo;

/**
 * @description:
 * @author: Fanchunshuai
 * @time: 2020/2/20 17:33
 * FIFO队列的bean模型
 */
public class FIFOQueueBean {
    /**
     * 集群节点目录一级分组
     */
    private String group;
    /**
     * 集群中的应用名称
     */
    private String appName;

    /**
     * 功能模块名称
     */
    private String busName;

    /**
     * 队列数据内容对象
     */
    private Object dataObject;


    public String getGroup() {
        return group;
    }

    public void setGroup(String group) {
        this.group = group;
    }

    public String getAppName() {
        return appName;
    }

    public void setAppName(String appName) {
        this.appName = appName;
    }

    public String getBusName() {
        return busName;
    }

    public void setBusName(String busName) {
        this.busName = busName;
    }

    public Object getDataObject() {
        return dataObject;
    }

    public void setDataObject(Object dataObject) {
        this.dataObject = dataObject;
    }
}

二、FIFO队列的基本操作接口

package com.coderman.zookeeper.clusterdemo.queuefifodemo;

import com.coderman.zookeeper.clusterdemo.ZKClientUtils;
import org.I0Itec.zkclient.ZkClient;

/**
 * @description:
 * @author: Fanchunshuai
 * @time: 2020/2/21 15:08
 * 定义一个先进先出队列的基本操作接口类
 */
public abstract class AbstractFIFOQueue {
    private ZKClientUtils zkClientUtils = new ZKClientUtils();
    ZkClient zkClient = zkClientUtils.getZkClient();
    public AbstractFIFOQueue(FIFOQueueBean queueFIFOBean){
        String nodePath = "/"+queueFIFOBean.getGroup()+"/"+queueFIFOBean.getAppName();
        if(!zkClient.exists(nodePath)){
            zkClient.createPersistent(nodePath,true);
        }
    }

    /**
     * 向队列中增加元素
     * @param queueFIFOBean
     */
    public abstract void produce(FIFOQueueBean queueFIFOBean);

    /**
     * 从队列中取数据
     * @return
     */
    public abstract Object consume(FIFOQueueBean queueFIFOBean);

    /**
     * 获取队列数据
     * @return
     */
    public abstract int getSize(FIFOQueueBean queueFIFOBean);

    /**
     * 获取节点信息
     * @param queueFIFOBean
     * @return
     */
    public  String getPersisteSequenceNode(FIFOQueueBean queueFIFOBean){
        return "/"+queueFIFOBean.getGroup()+"/"+queueFIFOBean.getAppName()+"/"+queueFIFOBean.getBusName();
    }

}

三、FIFO队列的实现类

package com.coderman.zookeeper.clusterdemo.queuefifodemo;

import com.coderman.zookeeper.clusterdemo.ZKClientUtils;
import org.I0Itec.zkclient.ZkClient;

/**
 * @description:
 * @author: Fanchunshuai
 * @time: 2020/2/21 15:08
 * 定义一个先进先出队列的基本操作接口类
 */
public abstract class AbstractFIFOQueue {
    private ZKClientUtils zkClientUtils = new ZKClientUtils();
    ZkClient zkClient = zkClientUtils.getZkClient();
    public AbstractFIFOQueue(FIFOQueueBean queueFIFOBean){
        String nodePath = "/"+queueFIFOBean.getGroup()+"/"+queueFIFOBean.getAppName();
        if(!zkClient.exists(nodePath)){
            zkClient.createPersistent(nodePath,true);
        }
    }

    /**
     * 向队列中增加元素
     * @param queueFIFOBean
     */
    public abstract void produce(FIFOQueueBean queueFIFOBean);

    /**
     * 从队列中取数据
     * @return
     */
    public abstract Object consume(FIFOQueueBean queueFIFOBean);

    /**
     * 获取队列数据
     * @return
     */
    public abstract int getSize(FIFOQueueBean queueFIFOBean);

    /**
     * 获取节点信息
     * @param queueFIFOBean
     * @return
     */
    public  String getPersisteSequenceNode(FIFOQueueBean queueFIFOBean){
        return "/"+queueFIFOBean.getGroup()+"/"+queueFIFOBean.getAppName()+"/"+queueFIFOBean.getBusName();
    }

}

四、main方法实践

package com.coderman.zookeeper.clusterdemo.queuefifodemo;

/**
 * @description:
 * @author: Fanchunshuai
 * @time: 2020/2/22 11:08
 */
public class FIFOQueueDemo {
    public static void main(String[] args) {
        FIFOQueueBean fifoBean = new FIFOQueueBean();
        fifoBean.setBusName("system-function-a");
        fifoBean.setAppName("company-a");
        fifoBean.setGroup("zkfifo");
        fifoBean.setDataObject(new Long(10000L));
        AbstractFIFOQueue fifoQueue = new FIFOQueue(fifoBean);
        fifoQueue.produce(fifoBean);
        fifoBean.setDataObject(new Long(10010L));
        fifoQueue.produce(fifoBean);
        fifoBean.setDataObject(new Long(10020L));
        fifoQueue.produce(fifoBean);
        fifoBean.setDataObject(new Long(10030L));
        fifoQueue.produce(fifoBean);
        fifoBean.setDataObject(new Long(10040L));
        fifoQueue.produce(fifoBean);
        int size = fifoQueue.getSize(fifoBean);
        System.out.println("size = "+size);

        Long num = (Long) fifoQueue.consume(fifoBean);
        System.out.println("num = "+num);
        Long num2 = (Long) fifoQueue.consume(fifoBean);
        System.out.println("num = "+num2);
        int size2 = fifoQueue.getSize(fifoBean);
        System.out.println("size2 = "+size2);
    }
}

总结：
zookeeper实现分布式的FIFO队列总结
1.zookeeper可以通过顺序节点的方式进行消息的存储，目录结构的组织
2.但是如果需要实现队列的更多api则需要更多接口
3.如果采用zk实现的FIFO在高并发需求下需要进行严格的测试
4.其他方案如redis可以参考Redis List的数据结构