Question

I have a search button, when the user clicks the search button the search() method is get called. I need to calculate the how much time it took to display the result to the user as we see in the google search.

This is my code.

        SimpleDateFormat sdfDate = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String strDate;
def startTime() { 
    Calendar cal = Calendar.getInstance();
    System.out.println("Current milliseconds since 13 Oct, 2008 are :"
    + cal.getTimeInMillis());
    long startTime=cal.getTimeInMillis();
    /*Date startNow = new Date();
    strDate = sdfDate.format(startNow);
    Date startTime=sdfDate.parse(strDate);
    print "startTime"+startTime*/
    return  startTime;

}
def endTime(){
    Calendar cal = Calendar.getInstance();
    System.out.println("Current milliseconds  :"
    + cal.getTimeInMillis());
    long endTime=cal.getTimeInMillis();
    /*Date endNow = new Date();
    print "endNow"+endNow
    strDate = sdfDate.format(endNow);
    Date endTime=sdfDate.parse(strDate);
    print "endTime"+endTime*/
    return endTime;
}

def differenceTime(long startTime,long endTime){
    print "requestEndTime"+endTime
    print "requestStartTime"+startTime
    long timeDifference = endTime - startTime;
    return timeDifference;
}

Here I am trying to get the starttime and endtime and trying to calculate the difference. I do know whether the way I implemented is right? Please tell me usually how the time difference is being calculated.

Answer 1

Instead of using Calendar it’s easier to use System.currentTimeMillis():

def startTime() { 
    long startTime=System.currentTimeMillis();
    return  startTime;
}

Calculating time difference based on System.currentTimeMillis() is very common in Java, and you’ll doing it right (I mean endTime - startTime)

So, your code could looks like:

long startTime = System.currentTimeMillis();
// .....
// processing request
// .....
long endTime = System.currentTimeMillis();
long differenceTime = endTime - startTime;
log.debug("Request time: " + differenceTime);
//or
log.debug("Request time: " + TimeUnit.MILLISECONDS.toSeconds(differenceTime) + " sec");