// The path to the documents directory.
String dataDir = Utils.getDataDir(GetWorkingHours.class);

long OneSec = 10000000;//microsecond * 10
long OneMin = 60 * OneSec;
long OneHour = 60 * OneMin;

Project project = new Project(dataDir + "BaselineTask.mpp");
Task task = project.getRootTask().getChildren().getById(1);

Calendar taskCalendar = task.get(Tsk.CALENDAR);

java.util.Calendar calStartDate = java.util.Calendar.getInstance();
calStartDate.setTime(task.get(Tsk.START));

java.util.Calendar calEndDate = java.util.Calendar.getInstance();
calEndDate.setTime(task.get(Tsk.FINISH));

java.util.Calendar tempDate = java.util.Calendar.getInstance();
tempDate = calStartDate;

Resource resource = project.getResources().getById(1);
Calendar resourceCalendar = resource.get(Rsc.CALENDAR);

//TimeSpan timeSpan;
long timeSpan = 0;

//Get Duration in Minutes
double durationInMins = 0;

while (tempDate.before(calEndDate))
{
    if (taskCalendar.isDayWorking(tempDate.getTime()) && resourceCalendar.isDayWorking(tempDate.getTime()))
    {
        timeSpan = (long) taskCalendar.getWorkingHours(tempDate.getTime());
        durationInMins = durationInMins + (timeSpan / OneMin);
    }
    tempDate.add(java.util.Calendar.DATE, 1);
}
tempDate.setTime(task.get(Tsk.START));

//Get Duration in Hours
double durationInHours = 0;

while (tempDate.before(calEndDate))
{
    if (taskCalendar.isDayWorking(tempDate.getTime()) && resourceCalendar.isDayWorking(tempDate.getTime()))
    {
        timeSpan = (long) taskCalendar.getWorkingHours(tempDate.getTime());
        durationInHours = durationInHours + (timeSpan / OneHour);
    }
    tempDate.add(java.util.Calendar.DATE, 1);
}
tempDate.setTime(task.get(Tsk.START));

//Get Duration in Days
double durationInDays = 0;

while (tempDate.before(calEndDate))
{
    if (taskCalendar.isDayWorking(tempDate.getTime()) && resourceCalendar.isDayWorking(tempDate.getTime()))
    {
        timeSpan = (long) taskCalendar.getWorkingHours(tempDate.getTime());
        if ((timeSpan / OneHour) > 0)
            durationInDays = durationInDays + (timeSpan/OneHour/8.0);
    }
    tempDate.add(java.util.Calendar.DATE, 1);
}
tempDate = calStartDate;

System.out.println("Duration in Minutes = " + durationInMins);
System.out.println("Duration in Hours = " + durationInHours);
System.out.println("Duration in Days = " + durationInDays);
System.out.println();