How to find time taken to run a Java program?

Question

I have a Java application that I\'ve been working on and I just realized that the program has to return a value in less than a minute, but don\'t know how to find or display

Answer 1

You can use 2 APIs provided by System class

1. System.currentTimeMillis() If code takes time in Millisecond range
2. System.nanoTime() If code takes time in Nanosecond range

Sample Code

public class TestTimeTaken {
    public static void main(String args[]) throws InterruptedException{
        long startTimeNanoSecond = System.nanoTime();
        long startTimeMilliSecond = System.currentTimeMillis();

        //code
        Thread.sleep(1000);
        //code

        long endTimeNanoSecond = System.nanoTime();
        long endTimeMilliSecond = System.currentTimeMillis();

        System.out.println("Time Taken in "+(endTimeNanoSecond - startTimeNanoSecond) + " ns");
        System.out.println("Time Taken in "+(endTimeMilliSecond - startTimeMilliSecond) + " ms");


    }
}