package com.caspar.util; 
import java.util.concurrent.locks.ReentrantLock;  
import org.apache.log4j.Logger; 
import redis.clients.jedis.Jedis; 
import redis.clients.jedis.JedisPool; 
import redis.clients.jedis.JedisPoolConfig;  
/** 
 * Redis 工具类 
 * @author caspar 
 * 
 */ 
public class RedisUtil { 
   
  protected static ReentrantLock lockPool = new ReentrantLock(); 
  protected static ReentrantLock lockJedis = new ReentrantLock(); 
   
  protected static Logger logger = Logger.getLogger(RedisUtil.class); 
   
  //Redis服务器IP 
  private static String ADDR_ARRAY = FileUtil.getPropertyValue("/properties/redis.properties", "server"); 
   
  //Redis的端口号 
  private static int PORT = FileUtil.getPropertyValueInt("/properties/redis.properties", "port"); 
   
  //访问密码 
//  private static String AUTH = FileUtil.getPropertyValue("/properties/redis.properties", "auth"); 
   
  //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 = FileUtil.getPropertyValueInt("/properties/redis.properties", "max_active");; 
   
  //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 = FileUtil.getPropertyValueInt("/properties/redis.properties", "max_idle");; 
   
  //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 = FileUtil.getPropertyValueInt("/properties/redis.properties", "max_wait");; 
 
  //超时时间 
  private static int TIMEOUT = FileUtil.getPropertyValueInt("/properties/redis.properties", "timeout");; 
   
  //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 = FileUtil.getPropertyValueBoolean("/properties/redis.properties", "test_on_borrow");; 
   
  private static JedisPool jedisPool = null; 
   
  /** 
   * redis过期时间,以秒为单位 
   */ 
  public final static int EXRP_HOUR = 60*60;     //一小时 
  public final static int EXRP_DAY = 60*60*24;    //一天 
  public final static int EXRP_MONTH = 60*60*24*30;  //一个月 
   
  /** 
   * 初始化Redis连接池 
   */ 
  private static void initialPool(){ 
    try { 
      JedisPoolConfig config = new JedisPoolConfig(); 
      config.setMaxTotal(MAX_ACTIVE); 
      config.setMaxIdle(MAX_IDLE); 
      config.setMaxWaitMillis(MAX_WAIT); 
      config.setTestOnBorrow(TEST_ON_BORROW); 
      jedisPool = new JedisPool(config, ADDR_ARRAY.split(",")[0], PORT, TIMEOUT); 
    } catch (Exception e) { 
      logger.error("First create JedisPool error : "+e); 
      try{ 
        //如果第一个IP异常，则访问第二个IP 
        JedisPoolConfig config = new JedisPoolConfig(); 
        config.setMaxTotal(MAX_ACTIVE); 
        config.setMaxIdle(MAX_IDLE); 
        config.setMaxWaitMillis(MAX_WAIT); 
        config.setTestOnBorrow(TEST_ON_BORROW); 
        jedisPool = new JedisPool(config, ADDR_ARRAY.split(",")[1], PORT, TIMEOUT); 
      }catch(Exception e2){ 
        logger.error("Second create JedisPool error : "+e2); 
      } 
    } 
  } 
   
   
  /** 
   * 在多线程环境同步初始化 
   */ 
  private static void poolInit() { 
    //断言 ，当前锁是否已经锁住，如果锁住了，就啥也不干，没锁的话就执行下面步骤 
    assert ! lockPool.isHeldByCurrentThread();  
    lockPool.lock(); 
    try {  
      if (jedisPool == null) {  
        initialPool(); 
      } 
    }catch(Exception e){ 
      e.printStackTrace(); 
    } finally {  
      lockPool.unlock(); 
    } 
  } 
   
   
  public static Jedis getJedis() { 
    //断言 ，当前锁是否已经锁住，如果锁住了，就啥也不干，没锁的话就执行下面步骤 
    assert ! lockJedis.isHeldByCurrentThread();  
    lockJedis.lock(); 
     
    if (jedisPool == null) {  
      poolInit(); 
    } 
    Jedis jedis = null; 
    try {  
      if (jedisPool != null) {  
        jedis = jedisPool.getResource();  
      } 
    } catch (Exception e) {  
      logger.error("Get jedis error : "+e); 
    }finally{ 
      returnResource(jedis); 
      lockJedis.unlock(); 
    } 
    return jedis; 
  }  
   
   
  /** 
   * 释放jedis资源 
   * @param jedis 
   */ 
  public static void returnResource(final Jedis jedis) { 
    if (jedis != null && jedisPool !=null) { 
      jedisPool.returnResource(jedis); 
    } 
  } 
 
  /** 
   * 设置 String 
   * @param key 
   * @param value 
   */ 
  public synchronized static void setString(String key ,String value){ 
    try { 
      value = StringUtil.isEmpty(value) ? "" : value; 
      getJedis().set(key,value); 
    } catch (Exception e) { 
      logger.error("Set key error : "+e); 
    } 
  } 
   
  /** 
   * 设置 过期时间 
   * @param key 
   * @param seconds 以秒为单位 
   * @param value 
   */ 
  public synchronized static void setString(String key ,int seconds,String value){ 
    try { 
      value = StringUtil.isEmpty(value) ? "" : value; 
      getJedis().setex(key, seconds, value); 
    } catch (Exception e) { 
      logger.error("Set keyex error : "+e); 
    } 
  } 
   
  /** 
   * 获取String值 
   * @param key 
   * @return value 
   */ 
  public synchronized static String getString(String key){ 
    if(getJedis() == null || !getJedis().exists(key)){ 
      return null; 
    } 
    return getJedis().get(key); 
  }    
}