Jedis使用

Jedis是java调用Redis的接口。

一。Maven中的jedis依赖包

 <!-- https://mvnrepository.com/artifact/redis.clients/jedis -->
         <dependency>
             <groupId>redis.clients</groupId>
             <artifactId>jedis</artifactId>
             <version>2.9.0</version>
         </dependency>

二。配置redis.properties.xml

 # *************** jedis connection parameters setting ************** #
 # redis server ip #
 redis.ip=127.0.0.1
 # redis server port #
 redis.port=6379
 # password
 redis.password=redis123

 # *************** jedis pool parameters setting ************** #
 # jedis's max connected objects #
 redis.pool.maxTotal=1000
 # jedis's max saved idel objects #
 redis.pool.maxIdle=10
 # jedis's max waiting time when no object returnd #
 redis.pool.maxWaitMillis=5000
 # whether test when jedis is calling borrowObject() #
 redis.pool.testOnBorrow=true
 # whether test when jedis is calling returnObject() #
 redis.pool.testOnReturn=true

三。编写JAVA类获取Jedis连接池

 import redis.clients.jedis.Jedis;
 import redis.clients.jedis.JedisPool;
 import redis.clients.jedis.JedisPoolConfig;

 import java.io.IOException;
 import java.util.Properties;

 /**
  * Created by XA on 2017/11/6.
  */
 public class MyJedisPool {

     private volatile static JedisPool pool;
     private static Jedis jedis;

     private static JedisPool getJedisPool() {
         if(pool==null) {
             synchronized (MyJedisPool.class) {
                 if(pool==null) {
                     try{
                         Properties props = new Properties();
                         props.load(MyJedisPool.class.getClassLoader().getResourceAsStream("config/redis.properties"));
                         // create jedis pool instance
                         JedisPoolConfig config = new JedisPoolConfig();
                         // set property items of jedis pool
                         config.setMaxTotal(Integer.valueOf(props.getProperty("redis.pool.maxTotal")));
                         config.setMaxIdle(Integer.valueOf(props.getProperty("redis.pool.maxIdle")));
                         config.setMaxWaitMillis(Integer.valueOf(props.getProperty("redis.pool.maxWaitMillis")));
                         config.setTestOnBorrow(Boolean.valueOf(props.getProperty("redis.pool.testOnBorrow")));
                         config.setTestOnReturn(Boolean.valueOf(props.getProperty("redis.pool.testOnReturn")));
                         // instance
                         pool = new JedisPool(config, props.getProperty("redis.ip"), Integer.valueOf(props.getProperty("redis.port")), 5000, props.getProperty("redis.password"));

                     }catch (IOException e) {
                         e.printStackTrace();
                     }
                 }
             }
         }
         return pool;
     }

     // get jedis
     public static Jedis getJedis() {
         return getJedisPool().getResource();
     }

     // recycle jedis
     public synchronized static void recycleJedis(Jedis jedis) {
         if(jedis!=null) {
             jedis.close();
         }
     }
 }

四。使用jedis的常用示例

public static void main(String[] args){
        try{
            Jedis jedis = MyJedisPool.getJedis();
            Set<String> keys = jedis.keys("*");
            System.out.println(keys.size());
        }catch (Exception e) {
            e.printStackTrace();
        }finally {
            MyJedisPool.recycleJedis(jedis);
        }

    }

注意：1. 不要忘记调用recycleJedis()回收jedis示例

　　　2. 实际调用recycleJedis()后发现，jedis仍然有效。原因暂时未知。

五。使用反射和泛型封装jedis的申请和回收

 @SuppressWarnings("unchecked")
     public static <T> T invokeJedisMethod(String methodName, Object[] args) {
         Jedis jedis = MyJedisPool.getJedis();

         T returnObject = null;
         try {
             Class[] argsTypes = new Class[args.length];
             for (int i = 0; i < args.length; i++) {
                 Class argClazz = args[i].getClass();
                 if (argClazz.equals(HashMap.class)) {
                     argsTypes[i] = Map.class;
                 } else {
                     argsTypes[i] = argClazz;
                 }

             }
             Method method = jedis.getClass().getDeclaredMethod(methodName, argsTypes);

             returnObject = (T) method.invoke(jedis, args);
         } catch (Exception e) {
             System.out.print(e.getStackTrace()[1].getClassName() + " --> " +
                     e.getStackTrace()[1].getMethodName() + " --> " +
                     e.getClass().getName() + "\n");
             e.printStackTrace();
         } finally {
             MyJedisPool.recycleJedis(jedis);
         }
         return returnObject;
     }

运行测试：

 import org.junit.Assert;
 import org.junit.Test;
 import org.springframework.test.annotation.Rollback;
 import org.springframework.transaction.annotation.Transactional;

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

 public class JedisServiceTest {

     public enum CommonAPI {
         // keys
         keys("keys", 1), del("del", 20), exists("exists", 22),
         // hash
         hget("hget", 2), hgetAll("hgetAll", 3), hset("hset", 4), hmset("hmset", 5), hlen("hlen", 6), hexists("hexists", 7), hdel("hdel", 8), hkeys("hkeys", 9), hmget("hmget", 23),
         // zsort
         zadd("zadd", 10), zrem("zrem", 11), zrange("zrange", 12), zcard("zcard", 13), zcount("zcount", 14),
         // list
         linsert("linsert", 15), llen("llen", 16), lpop("lpop", 17), lpush("lpush", 18), lrange("lrange", 19),
         // sub-pub
         subscribe("subscribe", 21);

         private String name;
         private int index;

         CommonAPI(String name, int index) {
             this.name = name;
             this.index = index;
         }

         public String getName() {
             return name;
         }
     }

     /**
      * 事务回滚无效，redis并不支持可回滚的事务
      */
     @Test
     @Transactional
     @Rollback
     public void invokeJedisMethod() {

         //
         JedisService.invokeJedisMethod(JedisService.CommonAPI.hset.getName(),  new Object[]{"key1", "hkey1", "value1"});
         Assert.assertTrue(JedisService.invokeJedisMethod(JedisService.CommonAPI.exists.getName(), "key1"));
         Set<String> keys = JedisService.invokeJedisMethod(JedisService.CommonAPI.keys.getName(), "key1");
         Assert.assertTrue(keys.contains("key1"));

         Assert.assertTrue(JedisService.invokeJedisMethod(JedisService.CommonAPI.hexists.getName(), new Object[] {"key1", "hkey1"}));
         Set<String> hkeys = JedisService.invokeJedisMethod(JedisService.CommonAPI.hkeys.getName(), "key1");
         Assert.assertTrue(hkeys.contains("hkey1"));

         Assert.assertEquals(JedisService.invokeJedisMethod(JedisService.CommonAPI.hget.getName(), new Object[] {"key1", "hkey1"}), "value1");

         JedisService.invokeJedisMethod(JedisService.CommonAPI.hdel.getName(), new Object[] {"key1", new String[]{"hkey1"}});
         Assert.assertFalse(JedisService.invokeJedisMethod(JedisService.CommonAPI.hexists.getName(), new Object[] {"key1", "hkey1"}));

         JedisService.invokeJedisMethod(JedisService.CommonAPI.del.getName(), "key1");
         Assert.assertFalse(JedisService.invokeJedisMethod(JedisService.CommonAPI.exists.getName(), "key1"));

         //
         Map<String, String> map = new HashMap<String, String>();
         map.put("hkey1", "hvalue1");map.put("hkey2", "hvalue2");
         JedisService.invokeJedisMethod(JedisService.CommonAPI.hmset.getName(), new Object[] {"key2", map});
         Assert.assertTrue(JedisService.invokeJedisMethod(JedisService.CommonAPI.exists.getName(), "key2"));
         Assert.assertTrue(JedisService.invokeJedisMethod(JedisService.CommonAPI.hexists.getName(), new Object[] {"key2", "hkey2"}));
         Assert.assertEquals(JedisService.invokeJedisMethod(JedisService.CommonAPI.hget.getName(), new Object[] {"key2", "hkey2"}), "hvalue2");
         Assert.assertEquals((long)JedisService.invokeJedisMethod(JedisService.CommonAPI.hlen.getName(), "key2"), map.size());

         Map<String, String> res = JedisService.invokeJedisMethod(JedisService.CommonAPI.hgetAll.getName(), "key2");
         Assert.assertEquals(res.size(), map.size());

         List<String> hvalues = JedisService.invokeJedisMethod(JedisService.CommonAPI.hmget.getName(), new Object[] {"key2", map.keySet().toArray(new String[map.size()])});
         Assert.assertEquals(hvalues.size(), 2);
         Assert.assertTrue(hvalues.contains("hvalue1"));
         Assert.assertTrue(hvalues.contains("hvalue2"));

         JedisService.invokeJedisMethod(JedisService.CommonAPI.del.getName(), "key2");
         Assert.assertFalse(JedisService.invokeJedisMethod(JedisService.CommonAPI.exists.getName(), "key2"));

     }

 }

测试全部通过。