How to calculate the sum of time

[maas]

Hello All,

I am having a jsp which is reading the total hours for each employee. However, I am reading their total hours from the DB and would like to sum the time at the grand total.

I tried to use:

 
Time total=rs.getTime("totalhours");
Time grandtotaltime =(00:00:00);
grandtotaltime = grandtotaltime + total;

But, an error is occurred that can not sum the time variable. So, how can I do that?

My code in the jsp is:

while (rs.next())   
  
                {   
                Time total=rs.getTime(totalhours");   
%>   
<tr>   
<td>   
<%=total%>   
</td>   
</tr>   
%>   
}   
<tr>   
<td>   
Grand Total =   
</td>   
</tr>

An example of the output:

7:15:00
0015:00

What I would like is
Grand Total = 7:30:00

Thanks for the help

[Junky]

The Calendar class has an add method. You could try converting your time objects and using Calendar instead.

Or you will just have to roll your own.

[maas]

Can you please show me in an example?

[DarrylBurke]

No, don't use Calendar. Calendar, util.Date, sql.Date and Time are all representations of an instant in time, not an interval.

You might want to take a look at Joda-Time which has a class Interval which

represents a period of time between two instants.

db

edit The still doesn't solve the issue of adding time intervals, sorry. It's probably better you roll your own -- add the times' millisecond value as longs.

[maas]

Thanks to your help.

But, can you please explain more since I am a beginner in Java

[Junky]

My bad. Misunderstood. Thought OP was trying to advance a certain period of time.

Maas what Daryl meant is that you should convert your time into seconds or milliseconds. So 1 hour = 3600 seconds. If you do that to all your times you can then add them up and then convert the result back to hours, minutes and seconds.