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javatimemillisecondsseconds

Time in milliseconds calculation

I have two string variables for timer i.e. 

String StartTimer1 = "00:00:00";
String EndTimer2 = "23:59:59";

Now , I need to calculate the time left from the present time (lets say if it is 05: 30:00) once the timer has started and time left has to be in milliseconds.

Solution

  • Here some tipps to get started:

    You can parse the String to a Java Date like this:

    SimpleDateFormat format = new SimpleDateFormat("HH:mm:ss");
Date startTimer1Date = format.parse(StartTimer1);

    You can get the current Date and Time like this:

    Date dateNow = new Date();

    And since you are working with time only (and not with date and time), you will need to manipulate the Date, Month and Year of all values to a common base, e.g. : 

    Calendar c = Calendar.getInstance();
c.setTime(dateNow);
c.set(Calendar.YEAR, 1970);
c.set(Calendar.DAY_OF_YEAR, 1);
dateNow = c.getTime();