java操作Redis之List

最新推荐文章于 2025-06-21 17:48:07 发布

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最新推荐文章于 2025-06-21 17:48:07 发布

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分类专栏： Redis

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package com.lyh.redis.test;

import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import org.junit.Test;

import redis.clients.jedis.Jedis;

public class SingleRedisTest2 {

    public Jedis init(){
        //一个Jedis对象对应这个一个Redis的实例
        Jedis jedis = new Jedis("192.168.29.160",6379);
        return jedis;
    }

    public void destroy(Jedis j){
        //在关闭时断开连接，测试发现在操作之前调用这个方法后Jedis实例依然可以使用
        j.disconnect();
    }

    @Test
    public void testList1(){
        System.out.println("1S=========================================");
        Jedis j = init();
        j.lpush("Friut","apple","banana","orange","xxx");
        System.out.println("llen(Friut):"+j.llen("Friut"));
        List<String> r = j.lrange("Friut",0,-1);
        for(String v :r){
            System.out.println("1range:"+v);
        }
        System.out.println("1E=========================================");

        System.out.println("2S=========================================");
        //从左边弹出一个元素,从左边进从组边出类似于一个栈
        String lpopValue = j.lpop("Friut");
        System.out.println("lpopValue:"+lpopValue+"   llen(Friut):"+j.llen("Friut"));

        List<String> rx = j.lrange("Friut",0,-1);
        for(String v :rx){
            System.out.println("2range:"+v);
        }
        System.out.println("2E=========================================");

        System.out.println("3S=========================================");
        //从Friut的右边弹出来一个元素并放入到另一个链表中(这个链表可以是存在的也可以是不存在的)
        j.rpoplpush("Friut","newList");
        List<String> lrange = j.lrange("newList",0,-1);
        for(String v : lrange){
            System.out.println("lrange:"+v);
        }
        System.out.println("3E=========================================");
//
        System.out.println("4S=========================================");
        //获取一个元素这个元素依然在链表中
        String lastElement = j.lindex("newList",j.llen("newList")-1);
        System.out.println("lastElement:"+lastElement);
        System.out.println("4E=========================================");
//
        System.out.println("5S=========================================");
        j.lset("newList", j.llen("newList")-1,"lsetValue");
        System.out.println("newList的最后一个值被设置为:"+j.rpop("newList"));
        System.out.println("5E=========================================");

        System.out.println("6S=========================================");
        //从左到有删除 apple元素 2次
        j.lrem("Friut",2,"apple");
        List<String> r1 = j.lrange("Friut",0,-1);
        for(String v :r1){
            System.out.println("1range:"+v);
        }
        System.out.println("6E=========================================");

        System.out.println("7S=========================================");
        //移除第4个到倒数第二个之外的所有元素
        j.ltrim("Friut",3,j.llen("Friut")-2);
        List<String> r3 = j.lrange("Friut",0,-1);
        for(String v :r3){
            System.out.println("1range:"+v);
        }
        System.out.println("7E=========================================");
        destroy(j);
    }

    @Test
    public void testList2(){
        Jedis j = init();
        String keyName = "r2";
        j.lpush(keyName,"A","B");

        int count = 3;
        CountDownLatch latch = new CountDownLatch(count);
        //由于在前面的队列中放入了2个元素现在要循环取3次所以必然会阻塞住
        //当手动使用命令往r2列表中添加元素后进程会结束
        Bget b = new Bget(j,count,TimeUnit.SECONDS,keyName, latch);
        new Thread(b).start();
        try {
            latch.await();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }finally{
            destroy(j);
        }
    }
}

/**
* 模拟Blpop
* @author MECHREVO
*/
class Bget implements Runnable{
    private Jedis j;
    private int count;
    private TimeUnit unit;
    private String keyName;
    private CountDownLatch latch;

    public Bget(){}

    public Bget(Jedis j,int count,TimeUnit unit,String keyName,CountDownLatch latch){
        this.j = j;
        this.count = count;
        this.unit = unit;
        this.keyName = keyName;
        this.latch = latch;
    }

    @Override
    public void run() {
        for(int i=0;i<count;i++){
            try{
                unit.sleep(1);
                //阻塞式获取如果keyName列表中没有元素则等待直到超时或者有新元素被添加
                List<String> blpop = j.blpop(100,keyName);
                if(null != blpop){
                    System.out.println(blpop.get(0)+"-----"+blpop.get(1));
                    latch.countDown();
                }
            }catch(InterruptedException e){
                e.printStackTrace();
            }
        }
        System.out.println("run over....");
    }
}