I’ll introduce how to measure program execution time in Java.

Simply wrap the target process before and after with System.currentTimeMillis() and look at the time difference.

public class Timing {
  public Timing() {}
  public void doSomething() {
    // Do some work
    // Here we simply sleep for 3 seconds
    try {
      Thread.sleep(3000);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }
  }
  public static void main(String[] args) {
    long start = System.currentTimeMillis(); // Start measurement
    Timing timing = new Timing();
    timing.doSomething();    // Call method to do some time-consuming work
    long stop = System.currentTimeMillis(); // End measurement
    System.out.println("実行にかかった時間は " + (stop - start) + " ミリ秒です。");
  }
}

That’s all from the Gemba where I wanted to measure speed in Java.

Reference Information

• JavaTips ～Javaプログラミング編：Javaプログラムの実行時間を計測する - ＠IT

That’s all from the Gemba.