StopWatch

public static void main(String[] args) {
  Long startTime = System.currentTimeMillis();
  // 你的业务代码
  Long endTime = System.currentTimeMillis();
  Long elapsedTime = (endTime - startTime) / 1000;
  System.out.println("该段总共耗时：" + elapsedTime + "s");
}

public static void main(String[] args) throws InterruptedException {
    StopWatch stopWatch = new StopWatch();

    // 任务一模拟休眠3秒钟
    stopWatch.start("TaskOneName");
    Thread.sleep(1000 * 3);
    System.out.println("当前任务名称：" + stopWatch.currentTaskName());
    stopWatch.stop();

    // 任务一模拟休眠10秒钟
    stopWatch.start("TaskTwoName");
    Thread.sleep(1000 * 10);
    System.out.println("当前任务名称：" + stopWatch.currentTaskName());
    stopWatch.stop();

    // 任务一模拟休眠10秒钟
    stopWatch.start("TaskThreeName");
    Thread.sleep(1000 * 10);
    System.out.println("当前任务名称：" + stopWatch.currentTaskName());
    stopWatch.stop();

    // 打印出耗时
    System.out.println(stopWatch.prettyPrint());
    System.out.println(stopWatch.shortSummary());
    // stop后它的值为null
    System.out.println(stopWatch.currentTaskName()); 
    
    // 最后一个任务的相关信息
    System.out.println(stopWatch.getLastTaskName());
    System.out.println(stopWatch.getLastTaskInfo());
    
    // 任务总的耗时  如果你想获取到每个任务详情（包括它的任务名、耗时等等）可使用
    System.out.println("所有任务总耗时：" + sw.getTotalTimeMillis());
    System.out.println("任务总数：" + sw.getTaskCount());
    System.out.println("所有任务详情：" + sw.getTaskInfo());
}