如何获取Java方法运行时间呢?

获取程序运行时间的实现思路
    1.程序运行前--获取当前时刻 
    2.放入业务逻辑代码
    3.获取当前时刻  
     结束时刻减去 开始时刻
        即可得到程序的运行时间

long startTime = System.nanoTime();
myCall(); 
long stopTime = System.nanoTime();
System.out.println(stopTime - startTime);


Java 8 中(输出格式为 ISO-8601):

Instant start = Instant.now();
Thread.sleep(63553);
Instant end = Instant.now();
System.out.println(Duration.between(start, end)); // prints PT1M3.553S
Guava Stopwatch :

Stopwatch stopwatch = Stopwatch.createStarted();
   myCall();
stopwatch.stop(); // optional
System.out.println("Time elapsed: "+ stopwatch.elapsed(TimeUnit.MILLISECONDS));