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 工具類 
 * @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服務器IP 
  private static String ADDR_ARRAY = FileUtil.getPropertyValue("/properties/redis.properties", "server"); 
   
  //Redis的端口號 
  private static int PORT = FileUtil.getPropertyValueInt("/properties/redis.properties", "port"); 
   
  //訪問密碼 
//  private static String AUTH = FileUtil.getPropertyValue("/properties/redis.properties", "auth"); 
   
  //可用連接實例的最大數目，默認值為8； 
  //如果賦值為-1，則表示不限制；如果pool已經分配了maxActive個jedis實例，則此時pool的狀態為exhausted(耗盡)。 
  private static int MAX_ACTIVE = FileUtil.getPropertyValueInt("/properties/redis.properties", "max_active");; 
   
  //控制一個pool最多有多少個狀態為idle(空閑的)的jedis實例，默認值也是8。 
  private static int MAX_IDLE = FileUtil.getPropertyValueInt("/properties/redis.properties", "max_idle");; 
   
  //等待可用連接的最大時間，單位毫秒，默認值為-1，表示永不超時。如果超過等待時間，則直接拋出JedisConnectionException； 
  private static int MAX_WAIT = FileUtil.getPropertyValueInt("/properties/redis.properties", "max_wait");; 
 
  //超時時間 
  private static int TIMEOUT = FileUtil.getPropertyValueInt("/properties/redis.properties", "timeout");; 
   
  //在borrow一個jedis實例時，是否提前進行validate操作；如果為true，則得到的jedis實例均是可用的； 
  private static boolean TEST_ON_BORROW = FileUtil.getPropertyValueBoolean("/properties/redis.properties", "test_on_borrow");; 
   
  private static JedisPool jedisPool = null; 
   
  /** 
   * redis過期時間,以秒為單位 
   */ 
  public final static int EXRP_HOUR = 60*60;     //一小時 
  public final static int EXRP_DAY = 60*60*24;    //一天 
  public final static int EXRP_MONTH = 60*60*24*30;  //一個月 
   
  /** 
   * 初始化Redis連接池 
   */ 
  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{ 
        //如果第一個IP異常，則訪問第二個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); 
      } 
    } 
  } 
   
   
  /** 
   * 在多線程環境同步初始化 
   */ 
  private static void poolInit() { 
    //斷言 ，當前鎖是否已經鎖住，如果鎖住了，就啥也不干，沒鎖的話就執行下面步驟 
    assert ! lockPool.isHeldByCurrentThread();  
    lockPool.lock(); 
    try {  
      if (jedisPool == null) {  
        initialPool(); 
      } 
    }catch(Exception e){ 
      e.printStackTrace(); 
    } finally {  
      lockPool.unlock(); 
    } 
  } 
   
   
  public static Jedis getJedis() { 
    //斷言 ，當前鎖是否已經鎖住，如果鎖住了，就啥也不干，沒鎖的話就執行下面步驟 
    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; 
  }  
   
   
  /** 
   * 釋放jedis資源 
   * @param jedis 
   */ 
  public static void returnResource(final Jedis jedis) { 
    if (jedis != null && jedisPool !=null) { 
      jedisPool.returnResource(jedis); 
    } 
  } 
 
  /** 
   * 設置 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); 
    } 
  } 
   
  /** 
   * 設置 過期時間 
   * @param key 
   * @param seconds 以秒為單位 
   * @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); 
    } 
  } 
   
  /** 
   * 獲取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); 
  }    
}