Java - How to calculate the total Time elapsed for a java method.
It is a standard requirement in a lot Java components/applications to find out the total time a method has taken to execute the call.Though there are several 3rd party libraries (Spring MethodInterceptor, java-InvocationHandler/DynamicProxy, and AspectOrientedProgramming) that offer method interceptor feature where the time can can be tracked.
Looking at greater need of this requirement of calculating precise time (NanoSeconds..) that a method spent on, Java5 has introduced a new TimeUnit class.
Please see below example for reference
public static String calculateTotalTimeElapsed(long startNanoSec, long endNanoSec) {
long difference = endNanoSec - startNanoSec;
String totalTimeString = String.format("%d Hours, %d Min, %d Sec, %d Millis, %d Micro, %d Nano",
TimeUnit.NANOSECONDS.toHours(difference), TimeUnit.NANOSECONDS.toMinutes(difference),
TimeUnit.NANOSECONDS.toSeconds(difference), TimeUnit.NANOSECONDS.toMillis(difference),
TimeUnit.NANOSECONDS.toMicros(difference), TimeUnit.NANOSECONDS.toNanos(difference));
return totalTimeString;
}
public static void main(String args[]){
long timeBefore1 = System.nanoTime();
//TODO: call any other function (db or resource intensive)
String timeString = calculateTotalTimeElapsed(timeBefore1, System.nanoTime());
System.out.println("Method has taken "+timeString);
}
output:
o Hours, 1 Min, 2 Sec, 400 Millis, 298 Micro, 12345 Nano.
