1. Jedis所需要的jar包
- Commons-pool-1.6.jar
- Jedis-2.1.0.jar
2. Jedis常用操作
1. 测试连通性
public class Demo01 {
public static void main(String[] args) {
//连接本地的 Redis 服务
Jedis jedis = new Jedis("127.0.0.1",6379);
//查看服务是否运行,打出pong表示OK
System.out.println("connection is OK==========>: "+jedis.ping());
}
}
2. 5 + 1
① 一个key
② 五大数据类型
import java.util.*;
import redis.clients.jedis.Jedis;
public class Test02
{
public static void main(String[] args)
{
Jedis jedis = new Jedis("127.0.0.1",6379);
//key
Set<String> keys = jedis.keys("*");
for (Iterator iterator = keys.iterator(); iterator.hasNext();) {
String key = (String) iterator.next();
System.out.println(key);
}
System.out.println("jedis.exists====>"+jedis.exists("k2"));
System.out.println(jedis.ttl("k1"));
//String
//jedis.append("k1","myreids");
System.out.println(jedis.get("k1"));
jedis.set("k4","k4_redis");
System.out.println("----------------------------------------");
jedis.mset("str1","v1","str2","v2","str3","v3");
System.out.println(jedis.mget("str1","str2","str3"));
//list
System.out.println("----------------------------------------");
//jedis.lpush("mylist","v1","v2","v3","v4","v5");
List<String> list = jedis.lrange("mylist",0,-1);
for (String element : list) {
System.out.println(element);
}
//set
jedis.sadd("orders","jd001");
jedis.sadd("orders","jd002");
jedis.sadd("orders","jd003");
Set<String> set1 = jedis.smembers("orders");
for (Iterator iterator = set1.iterator(); iterator.hasNext();) {
String string = (String) iterator.next();
System.out.println(string);
}
jedis.srem("orders","jd002");
System.out.println(jedis.smembers("orders").size());
//hash
jedis.hset("hash1","userName","lisi");
System.out.println(jedis.hget("hash1","userName"));
Map<String,String> map = new HashMap<String,String>();
map.put("telphone","13811814763");
map.put("address","atguigu");
map.put("email","abc@163.com");
jedis.hmset("hash2",map);
List<String> result = jedis.hmget("hash2", "telphone","email");
for (String element : result) {
System.out.println(element);
}
//zset
jedis.zadd("zset01",60d,"v1");
jedis.zadd("zset01",70d,"v2");
jedis.zadd("zset01",80d,"v3");
jedis.zadd("zset01",90d,"v4");
Set<String> s1 = jedis.zrange("zset01",0,-1);
for (Iterator iterator = s1.iterator(); iterator.hasNext();) {
String string = (String) iterator.next();
System.out.println(string);
}
}
}
3. 事务提交
① 日常
import redis.clients.jedis.Jedis;
import redis.clients.jedis.Response;
import redis.clients.jedis.Transaction;
public class Test03
{
public static void main(String[] args)
{
Jedis jedis = new Jedis("127.0.0.1",6379);
//监控key,如果该动了事务就被放弃
/*3
jedis.watch("serialNum");
jedis.set("serialNum","s#####################");
jedis.unwatch();*/
Transaction transaction = jedis.multi();//被当作一个命令进行执行
Response<String> response = transaction.get("serialNum");
transaction.set("serialNum","s002");
response = transaction.get("serialNum");
transaction.lpush("list3","a");
transaction.lpush("list3","b");
transaction.lpush("list3","c");
transaction.exec();
//2 transaction.discard();
System.out.println("serialNum***********"+response.get());
}
}
② 加锁
public class TestTransaction {
public boolean transMethod() {
Jedis jedis = new Jedis("127.0.0.1", 6379);
int balance;// 可用余额
int debt;// 欠额
int amtToSubtract = 10;// 实刷额度
jedis.watch("balance");
//jedis.set("balance","5");//此句不该出现,讲课方便。模拟其他程序已经修改了该条目
balance = Integer.parseInt(jedis.get("balance"));
if (balance < amtToSubtract) {
jedis.unwatch();
System.out.println("modify");
return false;
} else {
System.out.println("***********transaction");
Transaction transaction = jedis.multi();
transaction.decrBy("balance", amtToSubtract);
transaction.incrBy("debt", amtToSubtract);
transaction.exec();
balance = Integer.parseInt(jedis.get("balance"));
debt = Integer.parseInt(jedis.get("debt"));
System.out.println("*******" + balance);
System.out.println("*******" + debt);
return true;
}
}
/**
* 通俗点讲,watch命令就是标记一个键,如果标记了一个键, 在提交事务前如果该键被别人修改过,那事务就会失败,这种情况通常可以在程序中
* 重新再尝试一次。
* 首先标记了键balance,然后检查余额是否足够,不足就取消标记,并不做扣减; 足够的话,就启动事务进行更新操作,
* 如果在此期间键balance被其它人修改, 那在提交事务(执行exec)时就会报错, 程序中通常可以捕获这类错误再重新执行一次,直到成功。
*/
public static void main(String[] args) {
TestTransaction test = new TestTransaction();
boolean retValue = test.transMethod();
System.out.println("main retValue-------: " + retValue);
}
}
4. 主从复制
- 6379,6380启动,先各自先独立
- 主写
- 从读