06_Redis_java操作redis

Java操作redis

Java操作redis很简单。创建一个普通的Java工程。然后导入redis依赖的jar包。jar包我已经上传了。

1.入门级的demo

package com.bjsxt.test;

import redis.clients.jedis.Jedis;

public class RedisDemo {
	
	public static Jedis getJedis(){
		Jedis jedis = null;
		jedis = new Jedis(FinalCollention.IP, 6379);  //redis服务器的ip和端口
		jedis.auth(FinalCollention.PASSWORD);  //连接redis的密码
		return jedis;
	}
	public void test(){
		Jedis jedis = null;
		try{
			jedis = getJedis();
			jedis.incr("test");
			long dbsize = jedis.dbSize();
			System.out.println("数据库大小："+dbsize);
			System.out.println("测试test的值："+jedis.get("test"));
			
		}catch(Exception e){
			e.printStackTrace();
		}finally{
			if(jedis != null){
				jedis.disconnect();
			}
		}
	}
	public static void main(String[] args) {
		RedisDemo demo = new RedisDemo();
		demo.test();
	}
}

 

如果出现Java无法连接redis的异常，主要有三个方面的问题：

1.Java运行的主机ping一下redis服务器所在主机，看能否ping通

2.关闭redis服务器所在主机的防火墙

3.打开redis安装目录下的redis.conf文件。注释掉：bind 127.0.0.1这句话

# Accept connections on the specified port, default is 6379.
# If port 0 is specified Redis will not listen on a TCP socket.
port 6379

# If you want you can bind a single interface, if the bind option is not
# specified all the interfaces will listen for incoming connections.
#
# bind 127.0.0.1
"redis.conf" 597L, 25667C written

 特别说明：后面的实例，我就不使用try--catch了，但是自己写时一定要记着关闭连接

2.Java操作redis的各种数据结构

package com.bjsxt.test;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import redis.clients.jedis.Jedis;

public class RedisDataTypeDemo {
	
	public static Jedis getJedis(){
		Jedis jedis = null;
		jedis = new Jedis(FinalCollention.IP, 6379);  //redis服务器的ip和端口
		jedis.auth(FinalCollention.PASSWORD);  //连接redis的密码
		return jedis;
	}
	/**
	 * 
	 * @title demoKey
	 * @description 测试Key
	 * @author hadoop
	 */
	public void demoKey(){
		Jedis jedis = RedisDataTypeDemo.getJedis();
		System.out.println("查看键为aa的是否存在："+jedis.exists("aa"));
		System.out.println("查看键为aa的类型："+jedis.type("aa"));
		System.out.println("随机获得一个key："+jedis.randomKey());
		System.out.println("将aa重命名为bb："+jedis.rename("aa", "bb"));
		System.out.println("删除bb："+jedis.del("bb"));
		//从上面的方法可以看出，redis提供的接口方法名和redis-cli客户端提供的方法名是一样的，所以，只要对redis客户端的命令熟悉，那么Java操作redis就不是问题
	}
	/**
	 * 
	 * @title demoString
	 * @description 测试String
	 * @author hadoop
	 */
	public void demoString(){
		Jedis jedis = RedisDataTypeDemo.getJedis();
		System.out.println("设置name："+jedis.set("name", "小花"));
		System.out.println("设置name1："+jedis.set("name1", "小花1"));
		System.out.println("设置那么2："+jedis.set("name2", "小花2"));
		System.out.println("设置name，如果存在返回0："+jedis.setnx("name", "小花哈哈"));
		System.out.println("获取key为name和name1的value值："+jedis.mget("name","name1"));
		System.out.println("自增1："+jedis.incr("index"));
		System.out.println("自增1："+jedis.incr("index"));
		System.out.println("自增2："+jedis.incrBy("count", 2));
		System.out.println("自增2："+jedis.incrBy("count", 2));
		System.out.println("递减1："+jedis.decr("count"));
		System.out.println("递减2："+jedis.decrBy("index",2));
		System.out.println("在name后面添加String："+jedis.append("name", ",我爱你"));
		System.out.println("获取key为name的值："+jedis.get("name"));
		
	}
	/**
	 * 
	 * @title demoList
	 * @description 测试list数据类型
	 * @author hadoop
	 */
	public void demoList(){
		Jedis jedis = RedisDataTypeDemo.getJedis();
		//在头添加
		jedis.lpush("list", "hadoop","hbase","hive","pig","zookeeper");
		//在末尾添加
		jedis.rpush("list", "java","struts");
		//返回长度
		jedis.llen("list");
		//取值
		List<String> list = jedis.lrange("list", 0, -1);
		for (String string : list) {
			System.out.println(string);
		}
	}
	/**
	 * 
	 * @title demoSet
	 * @description 测试set数据类型
	 * @author hadoop
	 */
	public void demoSet(){
		Jedis jedis = RedisDataTypeDemo.getJedis();
		jedis.sadd("city", "北京","上海","重启","武汉");
		System.out.println("取出最上面的："+jedis.spop("city"));
		System.out.println("随机取出一个值"+jedis.srandmember("city"));
		jedis.sadd("city2", "北京","武汉","河北","张家界","辽林");
		System.out.println("交集："+jedis.sinter("city","city1"));
		System.out.println("并集："+jedis.sunion("city","city1"));
		System.out.println("差集："+jedis.sdiff("city","city1"));
		
	}
	/**
	 * 
	 * @title demoMap
	 * @description 测试map数据类型
	 * @author hadoop
	 */
	public void demoMap(){
		Jedis jedis = RedisDataTypeDemo.getJedis();
		jedis.hset("Mcity", "c1", "北京");
		System.out.println("取值："+jedis.hget("city", "c1"));
		Map<String,String> mcity = new HashMap<String, String>();
		mcity.put("c1", "桂林");
		mcity.put("c2", "天津");
		mcity.put("c3", "合肥");
		jedis.hmset("Mcity2", mcity);
		List<String> list =  jedis.hmget("Mcity2", "c1","c2","c3");
		for (String string : list) {
			System.out.println(string);
		}
		System.out.println(jedis.hlen("Mcity2"));
	}
	//测试
	public static void main(String[] args) {
		RedisDataTypeDemo rdr = new RedisDataTypeDemo();
		rdr.demoKey();
		rdr.demoList();
		rdr.demoMap();
		rdr.demoSet();
		rdr.demoString();
	}
}

 3.Java操作redis的管道

package com.bjsxt.test;

import redis.clients.jedis.Jedis;
import redis.clients.jedis.Pipeline;

public class RedisPipelineDemo {
	public static Jedis getJedis(){
		Jedis jedis = null;
		jedis = new Jedis(FinalCollention.IP, 6379);  //redis服务器的ip和端口
		jedis.auth(FinalCollention.PASSWORD);  //连接redis的密码
		return jedis;
	}
	
	public void hasPipeline(){
		Jedis jedis = RedisPipelineDemo.getJedis();
		System.out.println("开始："+System.currentTimeMillis());
		Pipeline pl = jedis.pipelined();
		for(int i = 0 ; i < 1000 ; i++){
			pl.incr("testPL");
		}
		pl.sync();
		System.out.println("开始："+System.currentTimeMillis());
	}
	
	public void noPipeline(){
		Jedis jedis = RedisPipelineDemo.getJedis();
		System.out.println("开始："+System.currentTimeMillis());
		for(int i = 0 ; i < 1000 ; i++){
			jedis.incr("testPL");
		}
		System.out.println("开始："+System.currentTimeMillis());
	}
}

 4.redis事务

package com.bjsxt.test;

import java.util.List;

import redis.clients.jedis.Jedis;
import redis.clients.jedis.Transaction;

public class RedisTXDemo {
	public static Jedis getJedis(){
		Jedis jedis = null;
		jedis = new Jedis(FinalCollention.IP, 6379);  //redis服务器的ip和端口
		jedis.auth(FinalCollention.PASSWORD);  //连接redis的密码
		return jedis;
	}
	/**
	 * 
	 * @title txDemo
	 * @description 没有异常的事务
	 * @author hadoop
	 */
	public void txDemo(){
		Jedis jedis = getJedis();
		//开启事务
		Transaction tx = jedis.multi();
		
		tx.set("txcity", "beijin");
		tx.sadd("hi", "abc");
		tx.get("txcity");
		List<Object> objs = tx.exec();
		
		for (Object object : objs) {
			System.out.println(object.toString());
		}
	}
	
	/**
	 * 
	 * @title txHasExDemo
	 * @description 含有异常的事务
	 * @author hadoop
	 */
	public void txHasExDemo(){
		Jedis jedis = getJedis();
		//开启事务
		Transaction tx = jedis.multi();
		
		tx.set("txcity1", "beijin");
		tx.sadd("hi1", "abc");
		int i = 1/0;
		tx.get("txcity1");
		List<Object> objs = tx.exec();
		
		for (Object object : objs) {
			System.out.println(object.toString());
		}
	}
	
	public static void main(String[] args) {
		RedisTXDemo redisTXDemo = new RedisTXDemo();
		redisTXDemo.txDemo();
		redisTXDemo.txHasExDemo();
	}
}

 从上面的方法可以看出，redis提供的接口方法名和redis-cli客户端提供的方法名是一样的，所以，只要对redis客户端的命令熟悉，那么Java操作redis就不是问题