JedisPool踩坑记录

package com.wang.distributedlock.utils;

import org.springframework.beans.factory.annotation.Value;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;

/**
 * @author wzq
 * @date 2020/05/29/11:09
 */
public class JedisPoolUtil {

    @Value("${redis.host}")
    private static final String HOST = "127.0.0.1";

    @Value("${redis.port}")
    private static final int PORT = 6379;

    @Value("${redis.password}")
    private static final String PASSWORD = "123456";

    private static volatile JedisPool jedisPool = null;

    public static JedisPool getJedisPoolInstance() {
        if (jedisPool == null) {
            JedisPoolConfig poolConfig = new JedisPoolConfig();
            // 最大连接数
            poolConfig.setMaxTotal(50);
            // 最大空闲连接数
            poolConfig.setMaxIdle(30);

            poolConfig.setMinIdle(10);
            // 最大等待时间
            poolConfig.setMaxWaitMillis(20 * 1000);
            // 检查连接可用性, 确保获取的redis实例可用
            // 在borrow一个jedis实例时，是否提前进行validate操作；如果为true，则得到的jedis实例均是可用的
            poolConfig.setTestOnBorrow(false);
            poolConfig.setTestOnCreate(false);

            // 无密码构造
            //jedisPool = new JedisPool(poolConfig, HOST, PORT);
            // 有密码构造，需要设置密码，设置密码可以在获取到jedis对象后，jedis.auth("密码")，也可以在此时使用构造入参设置
            jedisPool = new JedisPool(poolConfig, HOST, PORT, 10 * 1000, PASSWORD);

        }
        return jedisPool;
    }

    public static Jedis getJedisInstance() {
        Jedis jedis = getJedisPoolInstance().getResource();
        //jedis.auth("123456");
        return jedis;
    }

    public static void release(Jedis jedis) {
        jedis.close();
    }

}

package com.wang.distributedlock.zk;
import com.wang.distributedlock.utils.JedisPoolUtil;
import com.wang.distributedlock.utils.RedisTool;
import redis.clients.jedis.Jedis;
import java.util.UUID;
import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* @author wzq
* date: 2019/12/23 11:28
* description:
*/
public class OrderService implements Runnable {
private static CyclicBarrier cb = new CyclicBarrier(60);
// 订单号生成类
// 将orderNumGenerator或者count任意一处加上static，getNumber()加上同步锁，依然是线程安全的，因为使用的是同一个generator，而且加了锁是线程安全的
// 效果等同于静态锁，很多OrderService实例共用一把锁
private OrderNumGenerator orderNumGenerator = new OrderNumGenerator();
// 实现方式1
//private DistributeLock lock = new ZookeeperDistributeLock();
// 实现方式2
//private DistributeLock lock = new ZookeeperDistributeLock2();
/**
* 这么多OrderService实例共用一把锁，可以保证线程安全，但在集群部署多机模式下，
* 即便每台机器一次有一个请求获得锁，机器足够多依然会导致并发问题
*/
private static Lock rtLock = new ReentrantLock();
//实现方式3，redis分布式锁
//private Jedis jedis = RedisTool.getJedis();
private Jedis jedis = JedisPoolUtil.getJedisInstance();
public void run() {
try {
cb.await();
} catch (InterruptedException | BrokenBarrierException e) {
e.printStackTrace();
}
getNumber();
}
public void getNumber() {
String requestId = UUID.randomUUID().toString();
try {
//lock.getLock();
//rtLock.lock();
// Redis服务端单机部署,需要回调
// redis锁使用此段生成订单代码
/*if (RedisTool.tryGetDistributedLock(jedis, "lock", requestId, 2000)) {
String number = orderNumGenerator.getNumber();
System.out.println(Thread.currentThread().getName() + "-" + System.currentTimeMillis() + ",产生了订单:" + number);
} else {
this.getNumber();
}*/
// zookeeper锁或者不加锁使用此段生成代码订单
String number = orderNumGenerator.getNumber();
System.out.println(Thread.currentThread().getName() + "-" + System.currentTimeMillis() + ",产生了订单:" + number);
} catch (Exception e) {
e.printStackTrace();
} finally {
//lock.unlock();
//rtLock.unlock();
//Redis服务端单机部署,需要回调
//RedisTool.releaseDistributedLock(jedis, "lock", requestId);
}
}
public static void main(String[] args) {
System.out.println("####生成了订单####");
for (int i = 0; i < 60; i++) {
new Thread(new OrderService()).start();
}
}
}