TimeUnit的用法

Posted 2023-01-03

一、概述

TimeUnit是java.util.concurrent包下面的一个类，表示给定单元粒度的时间段
作用：
1、时间颗粒度转换
2、延时

TimeUnit类介绍

public enum TimeUnit 
    NANOSECONDS //纳秒
        public long toNanos(long d)    return d; 
        public long toMicros(long d)   return d/(C1/C0); 
        public long toMillis(long d)   return d/(C2/C0); 
        public long toSeconds(long d)  return d/(C3/C0); 
        public long toMinutes(long d)  return d/(C4/C0); 
        public long toHours(long d)    return d/(C5/C0); 
        public long toDays(long d)     return d/(C6/C0); 
        public long convert(long d, TimeUnit u)  return u.toNanos(d); 
        int excessNanos(long d, long m)  return (int)(d - (m*C2)); 
    ,
    MICROSECONDS // 微秒
        public long toNanos(long d)    return x(d, C1/C0, MAX/(C1/C0)); 
        public long toMicros(long d)   return d; 
        public long toMillis(long d)   return d/(C2/C1); 
        public long toSeconds(long d)  return d/(C3/C1); 
        public long toMinutes(long d)  return d/(C4/C1); 
        public long toHours(long d)    return d/(C5/C1); 
        public long toDays(long d)     return d/(C6/C1); 
        public long convert(long d, TimeUnit u)  return u.toMicros(d); 
        int excessNanos(long d, long m)  return (int)((d*C1) - (m*C2)); 
    ,
    MILLISECONDS //毫秒
        public long toNanos(long d)    return x(d, C2/C0, MAX/(C2/C0)); 
        public long toMicros(long d)   return x(d, C2/C1, MAX/(C2/C1)); 
        public long toMillis(long d)   return d; 
        public long toSeconds(long d)  return d/(C3/C2); 
        public long toMinutes(long d)  return d/(C4/C2); 
        public long toHours(long d)    return d/(C5/C2); 
        public long toDays(long d)     return d/(C6/C2); 
        public long convert(long d, TimeUnit u)  return u.toMillis(d); 
        int excessNanos(long d, long m)  return 0; 
    ,
    SECONDS //秒
        public long toNanos(long d)    return x(d, C3/C0, MAX/(C3/C0)); 
        public long toMicros(long d)   return x(d, C3/C1, MAX/(C3/C1)); 
        public long toMillis(long d)   return x(d, C3/C2, MAX/(C3/C2)); 
        public long toSeconds(long d)  return d; 
        public long toMinutes(long d)  return d/(C4/C3); 
        public long toHours(long d)    return d/(C5/C3); 
        public long toDays(long d)     return d/(C6/C3); 
        public long convert(long d, TimeUnit u)  return u.toSeconds(d); 
        int excessNanos(long d, long m)  return 0; 
    ,
    MINUTES //分
        public long toNanos(long d)    return x(d, C4/C0, MAX/(C4/C0)); 
        public long toMicros(long d)   return x(d, C4/C1, MAX/(C4/C1)); 
        public long toMillis(long d)   return x(d, C4/C2, MAX/(C4/C2)); 
        public long toSeconds(long d)  return x(d, C4/C3, MAX/(C4/C3)); 
        public long toMinutes(long d)  return d; 
        public long toHours(long d)    return d/(C5/C4); 
        public long toDays(long d)     return d/(C6/C4); 
        public long convert(long d, TimeUnit u)  return u.toMinutes(d); 
        int excessNanos(long d, long m)  return 0; 
    ,
    HOURS //时
        public long toNanos(long d)    return x(d, C5/C0, MAX/(C5/C0)); 
        public long toMicros(long d)   return x(d, C5/C1, MAX/(C5/C1)); 
        public long toMillis(long d)   return x(d, C5/C2, MAX/(C5/C2)); 
        public long toSeconds(long d)  return x(d, C5/C3, MAX/(C5/C3)); 
        public long toMinutes(long d)  return x(d, C5/C4, MAX/(C5/C4)); 
        public long toHours(long d)    return d; 
        public long toDays(long d)     return d/(C6/C5); 
        public long convert(long d, TimeUnit u)  return u.toHours(d); 
        int excessNanos(long d, long m)  return 0; 
    ,
    DAYS //天
        public long toNanos(long d)    return x(d, C6/C0, MAX/(C6/C0)); 
        public long toMicros(long d)   return x(d, C6/C1, MAX/(C6/C1)); 
        public long toMillis(long d)   return x(d, C6/C2, MAX/(C6/C2)); 
        public long toSeconds(long d)  return x(d, C6/C3, MAX/(C6/C3)); 
        public long toMinutes(long d)  return x(d, C6/C4, MAX/(C6/C4)); 
        public long toHours(long d)    return x(d, C6/C5, MAX/(C6/C5)); 
        public long toDays(long d)     return d; 
        public long convert(long d, TimeUnit u)  return u.toDays(d); 
        int excessNanos(long d, long m)  return 0; 
    ;

三、用法

延迟：

@Test
  public void  testTime()
    new Thread( new Runnable() 
       
           @Override
           public void run() 
               try 
          TimeUnit.SECONDS.sleep(10);
          System.out.println("延时10秒，完成了");
                catch (InterruptedException e) 
                   e.printStackTrace();
               
           
    ).start();
  

结合redis在项目中的使用

String key = RedisKeyUtils.getUserTokenKey(userId);
      BoundValueOperations<String, String> options = redisTemplate.boundValueOps(key);
      options.set(token);
      options.expire(15, TimeUnit.DAYS);