curator实现分布式锁和分布式计数器

实现分布式锁示例：

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.concurrent.CountDownLatch;
import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.locks.InterProcessMutex;
import org.apache.curator.retry.ExponentialBackoffRetry;


public class Lock2 {

    /** zookeeper地址 */
    static final String CONNECT_ADDR = "192.168.1.171:2181,192.168.1.172:2181,192.168.1.173:2181";
    /** session超时时间 */
    static final int SESSION_OUTTIME = 5000;//ms 
    
    static int count = 10;
    public static void genarNo(){
        try {
            count--;
            System.out.println(count);
        } finally {
        
        }
    }
    
    public static void main(String[] args) throws Exception {
        
        //1 重试策略：初试时间为1s 重试10次
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 10);
        //2 通过工厂创建连接
        CuratorFramework cf = CuratorFrameworkFactory.builder()
                    .connectString(CONNECT_ADDR)
                    .sessionTimeoutMs(SESSION_OUTTIME)
                    .retryPolicy(retryPolicy)
//                    .namespace("super")
                    .build();
        //3 开启连接
        cf.start();
        
        //4 分布式锁
        final InterProcessMutex lock = new InterProcessMutex(cf, "/super");
        //final ReentrantLock reentrantLock = new ReentrantLock();
        final CountDownLatch countdown = new CountDownLatch(1);
        
        for(int i = 0; i < 10; i++){
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        countdown.await();
                        //加锁
                        lock.acquire();
                        //reentrantLock.lock();
                        //-------------业务处理开始
                        //genarNo();
                        SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss|SSS");
                        System.out.println(sdf.format(new Date()));
                        //System.out.println(System.currentTimeMillis());
                        //-------------业务处理结束
                    } catch (Exception e) {
                        e.printStackTrace();
                    } finally {
                        try {
                            //释放
                            lock.release();
                            //reentrantLock.unlock();
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                    }
                }
            },"t" + i).start();
        }
        Thread.sleep(100);
        countdown.countDown();    
     
    }
}

 

实现分布式计数器示例：

import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.atomic.AtomicValue;
import org.apache.curator.framework.recipes.atomic.DistributedAtomicInteger;
import org.apache.curator.retry.ExponentialBackoffRetry;
import org.apache.curator.retry.RetryNTimes;

public class CuratorAtomicInteger {

    /** zookeeper地址 */
    static final String CONNECT_ADDR = "192.168.1.171:2181,192.168.1.172:2181,192.168.1.173:2181";
    /** session超时时间 */
    static final int SESSION_OUTTIME = 5000;//ms 
    
    public static void main(String[] args) throws Exception {
        
        //1 重试策略：初试时间为1s 重试10次
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 10);
        //2 通过工厂创建连接
        CuratorFramework cf = CuratorFrameworkFactory.builder()
                    .connectString(CONNECT_ADDR)
                    .sessionTimeoutMs(SESSION_OUTTIME)
                    .retryPolicy(retryPolicy)
                    .build();
        //3 开启连接
        cf.start();
        //cf.delete().forPath("/super");

        //4 使用DistributedAtomicInteger
        DistributedAtomicInteger atomicIntger = 
                new DistributedAtomicInteger(cf, "/super", new RetryNTimes(3, 1000));
        
        AtomicValue<Integer> value = atomicIntger.add(1);
        System.out.println(value.succeeded());
        System.out.println(value.postValue());    //最新值
        System.out.println(value.preValue());    //原始值
        
    }
}