StopWatch 的用法

统计输出总耗时

   public static void main(String[] args) throws Exception {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start("任务一");
        Thread.sleep(2000);
        stopWatch.stop();
        stopWatch.start("任务二");
        Thread.sleep(1000);
        stopWatch.stop();
        System.out.println(stopWatch.getTotalTimeNanos()); //纳秒 3006511215
        System.out.println(stopWatch.getTotalTimeMillis()); //毫秒 3003
        System.out.println(stopWatch.getTotalTimeSeconds()); //秒 3.005637544
    }

输出最后一个任务的耗时

 public static void main(String[] args) throws Exception {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start("任务一");
        Thread.sleep(2000);
        stopWatch.stop();
        stopWatch.start("任务er");
        Thread.sleep(1000);
        stopWatch.stop();
        System.out.println(stopWatch.getLastTaskTimeMillis()); //毫秒 1002
        System.out.println(stopWatch.getLastTaskTimeNanos()); //纳秒 1008902678
    }

以优雅的格式打出所有任务的耗时以及占比

 public static void main(String[] args) throws Exception {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start("任务一");
        Thread.sleep(2000);
        stopWatch.stop();
        stopWatch.start("任务er");
        Thread.sleep(1000);
        stopWatch.stop();
        System.out.println(stopWatch.prettyPrint());
    }
StopWatch '': running time = 3007597244 ns
---------------------------------------------
ns         %     Task name
---------------------------------------------
2003720282  067%  任务一
1003876962  033%  任务二

获取任务列表

    public static void main(String[] args) throws Exception {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start("任务一");
        Thread.sleep(2000);
        stopWatch.stop();
        stopWatch.start("任务二");
        Thread.sleep(1000);
        stopWatch.stop();
        StopWatch.TaskInfo[] taskInfo = stopWatch.getTaskInfo();
        for (StopWatch.TaskInfo info : taskInfo) {
            System.out.println(info.getTaskName());
        }
    }
任务一
任务二

其他方法

 public static void main(String[] args) throws Exception {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start("任务一");
        Thread.sleep(2000);
        stopWatch.stop();
        stopWatch.start("任务er");
        Thread.sleep(1000);
        stopWatch.stop();
        System.out.println(stopWatch.getTaskCount()); //获取任务数量
        System.out.println(stopWatch.getLastTaskName()); //获取最后一个任务名称
        System.out.println(stopWatch.getLastTaskInfo());//获取最后一个任务详情
    }