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Current system time

Return	Method	Summary
static long	nanoTime()	Returns the current value of the most precise available system timer, in nanoseconds.
static long	currentTimeMillis()	Returns the current time in milliseconds.


public class Main {

  public static void main(String args[]) {
    System.out.println(System.nanoTime());
    System.out.println(System.currentTimeMillis());
  }
}

The output:


238819728662434
1288461269875

The following code uses the System.currentTimeMillis() to check the performance of a for loop.


public class Main {
  public static void main(String args[]) {
    long start, end;

    System.out.println("Timing a for loop from 0 to 1,000,000");

   start = System.currentTimeMillis(); // get starting time
    for (int i = 0; i < 9999999; i++)
      ;
    end = System.currentTimeMillis(); // get ending time

    System.out.println("Elapsed time: " + (end - start));
  }
}

The output:


Timing a for loop from 0 to 1,000,000
Elapsed time: 16

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