利用zookeeper生成唯一id,通用性代碼

在上篇中是寫死的,這章就寫出通用的

package com.cxy.com.cxy.curator;



import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

import org.I0Itec.zkclient.ZkClient;
import org.I0Itec.zkclient.exception.ZkNodeExistsException;
import org.I0Itec.zkclient.serialize.BytesPushThroughSerializer;



public class IdMaker {

    private ZkClient client = null;
    private final String server;//記錄服務器的地址
    private final String root;//記錄父節點的路徑
    private final String nodeName;//節點的名稱
    private volatile boolean running = false;
    private ExecutorService cleanExector = null;

    //刪除節點的級別
    public enum RemoveMethod{
        NONE,IMMEDIATELY,DELAY

    }

    public IdMaker(String zkServer,String root,String nodeName){

        this.root = root;
        this.server = zkServer;
        this.nodeName = nodeName;

    }

    public void start() throws Exception {

        if (running)
            throw new Exception("server has stated...");
        running = true;

        init();

    }


    public void stop() throws Exception {

        if (!running)
            throw new Exception("server has stopped...");
        running = false;

        freeResource();

    }

    /**
     * 初始化服務資源
     */
    private void init(){

        client = new ZkClient(server,5000,5000,new BytesPushThroughSerializer());
        cleanExector = Executors.newFixedThreadPool(10);
        try{
            client.createPersistent(root,true);
        }catch (ZkNodeExistsException e){
            //ignore;
        }

    }

    /**
     * 釋放服務資源
     */
    private void freeResource(){

        cleanExector.shutdown();
        try{
            cleanExector.awaitTermination(2, TimeUnit.SECONDS);

        }catch(InterruptedException e){
            e.printStackTrace();
        }finally{
            cleanExector = null;
        }

        if (client!=null){
            client.close();
            client=null;

        }
    }

    /**
     * 檢測服務是否正在運行
     * @throws Exception
     */
    private void checkRunning() throws Exception {
        if (!running)
            throw new Exception("請先調用start");

    }

    private String ExtractId(String str){
        int index = str.lastIndexOf(nodeName);
        if (index >= 0){
            index+=nodeName.length();
            return index <= str.length()?str.substring(index):"";
        }
        return str;

    }

    /**
     * 產生ID
     * 核心函數
     * @param removeMethod 刪除的方法
     * @return
     * @throws Exception
     */
    public String generateId(RemoveMethod removeMethod) throws Exception{
        checkRunning();
        final String fullNodePath = root.concat("/").concat(nodeName);
        //返回創建的節點的名稱
        //final String ourPath = client.createPersistentSequential(fullNodePath, null);
        final String ourPath = client.createEphemeralSequential(fullNodePath, null);

        System.out.println(ourPath);

        /**
         * 在創建完節點后為了不占用太多空間，可以選擇性刪除模式
         */
        if (removeMethod.equals(RemoveMethod.IMMEDIATELY)){
            client.delete(ourPath);
        }else if (removeMethod.equals(RemoveMethod.DELAY)){
            cleanExector.execute(new Runnable() {

                public void run() {
                    // TODO Auto-generated method stub
                    client.delete(ourPath);
                }
            });

        }
        //node-0000000000, node-0000000001，ExtractId提取ID
        return ExtractId(ourPath);
    }

}

測試:

package com.cxy.com.cxy.curator;

/***
 * @ClassName: TestIdMaker
 * @Description:
 * @Auther: cxy
 * @Date: 2019/1/30:17:15
 * @version : V1.0
 */
public class TestIdMaker {
    public static void main(String[] args) throws Exception {

        IdMaker idMaker = new IdMaker("127.0.0.1:2181",
                "/NameService/IdGen", "ID");
        idMaker.start();

        try {
            for (int i = 0; i < 10; i++) {
                String id = idMaker.generateId(IdMaker.RemoveMethod.NONE);
                System.out.println(id);

            }
        } finally {
            idMaker.stop();

        }
    }
}