从此弃用时间戳相减的方式来计算运行时间。 

import org.apache.commons.lang.time.StopWatch;import org.junit.Test;public class Test1 {	@Test	public void test_StopWatch() throws InterruptedException	{						StopWatch stopWatch = new StopWatch();		stopWatch.start();		//Thread.sleep(1000);		for(int i=0;i<1000;i++)		{			Thread.sleep(1);		}		stopWatch.stop();		System.out.println(stopWatch.getTime());		//System.out.println(sw.toString());	}}