Compute and display elapsed time of an operation

Sometimes you want to compute the time a certain operation takes, which can be done by using the currentTimeMillis() method of the System class.
The value returned is the current time in milliseconds and by calling the method before and after the operation you can compute the difference in time,
which is the time of the operation.
The example below performs and operation by looping from 0 to 9 and in each loop makes the thread sleep for 60 milliseconds and then displays the time elapsed
between the start and the end of this operation.

/**
* Main.java
*
* @author www.javadb.com
*/
public class Main {

    /**
     * Counts and displays elapsed time between two points in time.
     *
     */
    public void computeAndDisplayElapsedTime() {

        long startTime = System.currentTimeMillis();

        for (int i = 0; i < 10; i++) {
            try {

                Thread.sleep(60);

            } catch (InterruptedException ex) {
                ex.printStackTrace();
            }
        }

        long endTime = System.currentTimeMillis();

        float seconds = (endTime - startTime) / 1000F;

        System.out.println(Float.toString(seconds) + " seconds.");


    }
    /**
     * Starts the program
     *
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        new Main().computeAndDisplayElapsedTime();
    }
}

This is what the output looked like:

0.609 seconds.

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