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Sample code for using Jedis to operate Redis in Java

高洛峰
高洛峰Original
2017-01-21 16:26:481200browse

Using Java to operate Redis requires jedis-2.1.0.jar, download address: jedis-2.1.0.jar

If you need to use the Redis connection pool, you also need commons-pool-1.5.4. jar, download address: commons-pool-1.5.4.jar

package com.test;
 
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
 
import org.junit.Before;
import org.junit.Test;
 
import redis.clients.jedis.Jedis;
 
public class TestRedis {
  private Jedis jedis; 
   
  @Before
  public void setup() {
    //连接redis服务器,192.168.0.100:6379
    jedis = new Jedis("192.168.0.100", 6379);
    //权限认证
    jedis.auth("admin"); 
  }
   
  /**
   * redis存储字符串
   */
  @Test
  public void testString() {
    //-----添加数据---------- 
    jedis.set("name","xinxin");//向key-->name中放入了value-->xinxin 
    System.out.println(jedis.get("name"));//执行结果:xinxin 
     
    jedis.append("name", " is my lover"); //拼接
    System.out.println(jedis.get("name")); 
     
    jedis.del("name"); //删除某个键
    System.out.println(jedis.get("name"));
    //设置多个键值对
    jedis.mset("name","liuling","age","23","qq","476777XXX");
    jedis.incr("age"); //进行加1操作
    System.out.println(jedis.get("name") + "-" + jedis.get("age") + "-" + jedis.get("qq"));
     
  }
   
  /**
   * redis操作Map
   */
  @Test
  public void testMap() {
    //-----添加数据---------- 
    Map<String, String> map = new HashMap<String, String>();
    map.put("name", "xinxin");
    map.put("age", "22");
    map.put("qq", "123456");
    jedis.hmset("user",map);
    //取出user中的name,执行结果:[minxr]-->注意结果是一个泛型的List 
    //第一个参数是存入redis中map对象的key,后面跟的是放入map中的对象的key,后面的key可以跟多个,是可变参数 
    List<String> rsmap = jedis.hmget("user", "name", "age", "qq");
    System.out.println(rsmap); 
  
    //删除map中的某个键值 
    jedis.hdel("user","age");
    System.out.println(jedis.hmget("user", "age")); //因为删除了,所以返回的是null 
    System.out.println(jedis.hlen("user")); //返回key为user的键中存放的值的个数2 
    System.out.println(jedis.exists("user"));//是否存在key为user的记录 返回true 
    System.out.println(jedis.hkeys("user"));//返回map对象中的所有key 
    System.out.println(jedis.hvals("user"));//返回map对象中的所有value 
  
    Iterator<String> iter=jedis.hkeys("user").iterator(); 
    while (iter.hasNext()){ 
      String key = iter.next(); 
      System.out.println(key+":"+jedis.hmget("user",key)); 
    } 
  }
   
  /** 
   * jedis操作List 
   */
  @Test
  public void testList(){ 
    //开始前,先移除所有的内容 
    jedis.del("java framework"); 
    System.out.println(jedis.lrange("java framework",0,-1)); 
    //先向key java framework中存放三条数据 
    jedis.lpush("java framework","spring"); 
    jedis.lpush("java framework","struts"); 
    jedis.lpush("java framework","hibernate"); 
    //再取出所有数据jedis.lrange是按范围取出, 
    // 第一个是key,第二个是起始位置,第三个是结束位置,jedis.llen获取长度 -1表示取得所有 
    System.out.println(jedis.lrange("java framework",0,-1)); 
     
    jedis.del("java framework");
    jedis.rpush("java framework","spring"); 
    jedis.rpush("java framework","struts"); 
    jedis.rpush("java framework","hibernate"); 
    System.out.println(jedis.lrange("java framework",0,-1));
  } 
   
  /** 
   * jedis操作Set 
   */
  @Test
  public void testSet(){ 
    //添加 
    jedis.sadd("user","liuling"); 
    jedis.sadd("user","xinxin"); 
    jedis.sadd("user","ling"); 
    jedis.sadd("user","zhangxinxin");
    jedis.sadd("user","who"); 
    //移除noname 
    jedis.srem("user","who"); 
    System.out.println(jedis.smembers("user"));//获取所有加入的value 
    System.out.println(jedis.sismember("user", "who"));//判断 who 是否是user集合的元素 
    System.out.println(jedis.srandmember("user")); 
    System.out.println(jedis.scard("user"));//返回集合的元素个数 
  } 
  
  @Test
  public void test() throws InterruptedException { 
    //jedis 排序 
    //注意,此处的rpush和lpush是List的操作。是一个双向链表(但从表现来看的) 
    jedis.del("a");//先清除数据,再加入数据进行测试 
    jedis.rpush("a", "1"); 
    jedis.lpush("a","6"); 
    jedis.lpush("a","3"); 
    jedis.lpush("a","9"); 
    System.out.println(jedis.lrange("a",0,-1));// [9, 3, 6, 1] 
    System.out.println(jedis.sort("a")); //[1, 3, 6, 9] //输入排序后结果 
    System.out.println(jedis.lrange("a",0,-1)); 
  } 
   
  @Test
  public void testRedisPool() {
    RedisUtil.getJedis().set("newname", "中文测试");
    System.out.println(RedisUtil.getJedis().get("newname"));
  }
}

Redis connection pool:

package com.test;
 
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
 
public final class RedisUtil {
   
  //Redis服务器IP
  private static String ADDR = "192.168.0.100";
   
  //Redis的端口号
  private static int PORT = 6379;
   
  //访问密码
  private static String AUTH = "admin";
   
  //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)。
  private 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。
  private 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;
  private static int MAX_WAIT = 10000;
   
  private static int TIMEOUT = 10000;
   
  //在borrow一个jedis实例时,是否提前进行validate操作;如果为true,则得到的jedis实例均是可用的;
  private static boolean TEST_ON_BORROW = true;
   
  private static JedisPool jedisPool = null;
   
  /**
   * 初始化Redis连接池
   */
  static {
    try {
      JedisPoolConfig config = new JedisPoolConfig();
      config.setMaxActive(MAX_ACTIVE);
      config.setMaxIdle(MAX_IDLE);
      config.setMaxWait(MAX_WAIT);
      config.setTestOnBorrow(TEST_ON_BORROW);
      jedisPool = new JedisPool(config, ADDR, PORT, TIMEOUT, AUTH);
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
   
  /**
   * 获取Jedis实例
   * @return
   */
  public synchronized static Jedis getJedis() {
    try {
      if (jedisPool != null) {
        Jedis resource = jedisPool.getResource();
        return resource;
      } else {
        return null;
      }
    } catch (Exception e) {
      e.printStackTrace();
      return null;
    }
  }
   
  /**
   * 释放jedis资源
   * @param jedis
   */
  public static void returnResource(final Jedis jedis) {
    if (jedis != null) {
      jedisPool.returnResource(jedis);
    }
  }
}

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