redis分布式锁-lua脚本

package com.tuling.jedis;

import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;

import java.io.IOException;
import java.util.Arrays;

/**
 * 访问redis单机
 *
 * @author 
 */
public class JedisSingleTest {
    public static void main(String[] args) throws IOException {

        JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
        jedisPoolConfig.setMaxTotal(20);
        jedisPoolConfig.setMaxIdle(10);
        jedisPoolConfig.setMinIdle(5);

        // timeout，这里既是连接超时又是读写超时，从Jedis 2.8开始有区分connectionTimeout和soTimeout的构造函数
        JedisPool jedisPool = new JedisPool(jedisPoolConfig, "139.129.99.13", 6379, 3000, "");

        Jedis jedis = null;
        try {
            //从redis连接池里拿出一个连接执行命令
            jedis = jedisPool.getResource();

            //******* jedis普通操作示例 ********
            /*System.out.println(jedis.set("single1", "zhuge"));
            System.out.println(jedis.get("single1"));*/

            //******* 管道示例 ********
            //管道的命令执行方式：cat redis.txt | redis-cli -h 127.0.0.1 -a password - p 6379 --pipe
            /*Pipeline pl = jedis.pipelined();
            for (int i = 0; i < 10; i++) {
                pl.incr("pipelineKey");
                pl.set("zhuge" + i, "zhuge");
            }
            List<Object> results = pl.syncAndReturnAll();
            System.out.println(results);*/

            //******* lua脚本示例 ********
            //模拟一个商品减库存的原子操作
            //lua脚本命令执行方式：redis-cli --eval /tmp/test.lua , 10
            jedis.set("product_stock_10016", "15");  //初始化商品10016的库存
            String script = " local count = redis.call('get', KEYS[1]) " +
                            " local a = tonumber(count) " +
                            " local b = tonumber(ARGV[1]) " +
                            " if a >= b then " +
                            "   redis.call('set', KEYS[1], count-b) " +
                            //模拟语法报错回滚操作"   bb == 0 " +
                            "   return 1 " +
                            " end " +
                            " return 0 ";
            Object obj = jedis.eval(script, Arrays.asList("product_stock_10016"), Arrays.asList("10"));
            System.out.println(obj);

        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            //注意这里不是关闭连接，在JedisPool模式下，Jedis会被归还给资源池。
            if (jedis != null)
                jedis.close();
        }
    }
}