来源:朱小厮
链接:http://blog.csdn.net/u013256816/article/details/51125842
通过前一篇《redis的简单使用》的简单介绍,本篇主要阐述Jedis对redis的五大类型的操作:字符串、列表、散列、集合、有序集合。
这里的测试用例采用junit4进行运行,准备代码如下:
private static final String ipAddr = '10.10.195.112';
private static final int port = 6379;
private static Jedis jedis= null;
@BeforeClass
public static void init()
{
jedis = JedisUtil.getInstance().getJedis(ipAddr, port);
}
@AfterClass
public static void close()
{
JedisUtil.getInstance().closeJedis(jedis,ipAddr, port);
}
其中JedisUtil是对jedis做的简单封装,代码如下:
import org.apache.log4j.Logger;
import java.util.HashMap;
import java.util.Map;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
public class JedisUtil
{
private Logger logger = Logger.getLogger(this.getClass().getName());
private JedisUtil(){}
private static class RedisUtilHolder{
private static final JedisUtil instance = new JedisUtil();
}
public static JedisUtil getInstance(){
return RedisUtilHolder.instance;
}
private static Map
maps = new HashMap ();
private static JedisPool getPool(String ip, int port){
String key = ip+':'+port;
JedisPool pool = null;
if(!maps.containsKey(key))
{
JedisPoolConfig config = new JedisPoolConfig();
config.setMaxActive(RedisConfig.MAX_ACTIVE);
config.setMaxIdle(RedisConfig.MAX_IDLE);
config.setMaxWait(RedisConfig.MAX_WAIT);
config.setTestOnBorrow(true);
config.setTestOnReturn(true);
pool = new JedisPool(config,ip,port,RedisConfig.TIMEOUT);
maps.put(key, pool);
}
else
{
pool = maps.get(key);
}
return pool;
}
public Jedis getJedis(String ip, int port)
{
Jedis jedis = null;
int count = 0;
do
{
try
{
jedis = getPool(ip,port).getResource();
}
catch (Exception e)
{
logger.error('get redis master1 failed!',e);
getPool(ip,port).returnBrokenResource(jedis);
}
}
while(jedis == null && count<>
return jedis;
}
public void closeJedis(Jedis jedis, String ip, int port){
if(jedis != null)
{
getPool(ip,port).returnResource(jedis);
}
}
}
public class RedisConfig
{
//可用连接实例的最大数目,默认值为8;
//如果赋值为-1,则表示不限制;如果pool已经分配了maxActive个jedis实例,则此时pool的状态为exhausted(耗尽)。
public static int MAX_ACTIVE = 1024;
//控制一个pool最多有多少个状态为idle(空闲的)的jedis实例,默认值也是8。
public static int MAX_IDLE = 200;
//等待可用连接的最大时间,单位毫秒,默认值为-1,表示永不超时。如果超过等待时间,则直接抛出JedisConnectionException;
public static int MAX_WAIT = 10000;
public static int TIMEOUT = 10000;
public static int RETRY_NUM = 5;
}
键操作
@Test public void testKey() throws InterruptedException
{
System.out.println('清空数据:'+jedis.flushDB());
System.out.println('判断某个键是否存在:'+jedis.exists('username'));
System.out.println('新增<'username','zzh'>的键值对:'+jedis.set('username', 'zzh'));'username','zzh'>
System.out.println(jedis.exists('name'));
System.out.println('新增<'password','password'>的键值对:'+jedis.set('password', 'password'));'password','password'>
System.out.print('系统中所有的键如下:');
Set
keys = jedis.keys('*'); System.out.println(keys);
System.out.println('删除键password:'+jedis.del('password'));
System.out.println('判断键password是否存在:'+jedis.exists('password'));
System.out.println('设置键username的过期时间为5s:'+jedis.expire('username', 5));
TimeUnit.SECONDS.sleep(2);
System.out.println('查看键username的剩余生存时间:'+jedis.ttl('username'));
System.out.println('移除键username的生存时间:'+jedis.persist('username'));
System.out.println('查看键username的剩余生存时间:'+jedis.ttl('username'));
System.out.println('查看键username所存储的值的类型:'+jedis.type('username'));
}
输出结果:
清空数据:OK
判断某个键是否存在:false
新增<'username','zzh'>的键值对:OK'username','zzh'>
false
新增<'password','password'>的键值对:OK'password','password'>
系统中所有的键如下:[username, password]
删除键password:1
判断键password是否存在:false
设置键username的过期时间为5s:1
查看键username的剩余生存时间:3
移除键username的生存时间:1
查看键username的剩余生存时间:-1
查看键username所存储的值的类型:string
在Redis里面,字符串可以存储三种类型的值:
字节串(byte string)
整数
浮点数
@Test public void testString() throws InterruptedException
{
jedis.flushDB();
System.out.println('===========增加数据===========');
System.out.println(jedis.set('key1','value1'));
System.out.println(jedis.set('key2','value2'));
System.out.println(jedis.set('key3', 'value3'));
System.out.println('删除键key2:'+jedis.del('key2'));
System.out.println('获取键key2:'+jedis.get('key2'));
System.out.println('修改key1:'+jedis.set('key1', 'value1Changed'));
System.out.println('获取key1的值:'+jedis.get('key1'));
System.out.println('在key3后面加入值:'+jedis.append('key3', 'End'));
System.out.println('key3的值:'+jedis.get('key3'));
System.out.println('增加多个键值对:'+jedis.mset('key01','value01','key02','value02','key03','value03'));
System.out.println('获取多个键值对:'+jedis.mget('key01','key02','key03'));
System.out.println('获取多个键值对:'+jedis.mget('key01','key02','key03','key04'));
System.out.println('删除多个键值对:'+jedis.del(new String[]{'key01','key02'}));
System.out.println('获取多个键值对:'+jedis.mget('key01','key02','key03'));
jedis.flushDB();
System.out.println('===========新增键值对防止覆盖原先值==============');
System.out.println(jedis.setnx('key1', 'value1'));
System.out.println(jedis.setnx('key2', 'value2'));
System.out.println(jedis.setnx('key2', 'value2-new'));
System.out.println(jedis.get('key1'));
System.out.println(jedis.get('key2'));
System.out.println('===========新增键值对并设置有效时间=============');
System.out.println(jedis.setex('key3', 2, 'value3'));
System.out.println(jedis.get('key3'));
TimeUnit.SECONDS.sleep(3);
System.out.println(jedis.get('key3'));
System.out.println('===========获取原值,更新为新值==========');//GETSET is an atomic set this value and return the old value command.
System.out.println(jedis.getSet('key2', 'key2GetSet'));
System.out.println(jedis.get('key2'));
System.out.println('获得key2的值的字串:'+jedis.getrange('key2', 2, 4));
}
输出结果:
===========增加数据===========
OK
OK
OK
删除键key2:1
获取键key2:null
修改key1:OK
获取key1的值:value1Changed
在key3后面加入值:9
key3的值:value3End
增加多个键值对:OK
获取多个键值对:[value01, value02, value03]
获取多个键值对:[value01, value02, value03, null]
删除多个键值对:2
获取多个键值对:[null, null, value03]
===========新增键值对防止覆盖原先值==============
1
1
0
value1
value2
===========新增键值对并设置有效时间=============
OK
value3
null
===========获取原值,更新为新值==========
value2
key2GetSet
获得key2的值的字串:y2G
memcached和redis同样有append的操作,但是memcached有prepend的操作,redis中并没有。
@Test public void testNumber()
{
jedis.flushDB();
jedis.set('key1', '1');
jedis.set('key2', '2');
jedis.set('key3', '2.3');
System.out.println('key1的值:'+jedis.get('key1'));
System.out.println('key2的值:'+jedis.get('key2'));
System.out.println('key1的值加1:'+jedis.incr('key1'));
System.out.println('获取key1的值:'+jedis.get('key1'));
System.out.println('key2的值减1:'+jedis.decr('key2'));
System.out.println('获取key2的值:'+jedis.get('key2'));
System.out.println('将key1的值加上整数5:'+jedis.incrBy('key1', 5));
System.out.println('获取key1的值:'+jedis.get('key1'));
System.out.println('将key2的值减去整数5:'+jedis.decrBy('key2', 5));
System.out.println('获取key2的值:'+jedis.get('key2'));
}
输出结果:
key1的值:1
key2的值:2
key1的值加1:2
获取key1的值:2
key2的值减1:1
获取key2的值:1
将key1的值加上整数5:7
获取key1的值:7
将key2的值减去整数5:-4
获取key2的值:-4
在redis2.6或以上版本中有这个命令:incrbyfloat,即将键存储的值加上浮点数amount,jedis-2.1.0中不支持这一操作。
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