Java Calendar Dates

Hi all,

I am currently building a payroll software code and stuck at a point, I would do my best to explain and get any help

I have a pay period Start date and End Date this can be any period

When I enter the period as (in mm/dd/yyyy format)

Start date "04/08/2010"
End Date "05/08/2010"

then I add 1 month to a calendar handler.add(Calendar.Month,1)

the next and the corresponding dates are

Start date "05/08/2010"
End Date "06/08/2010"

Start date "06/08/2010"
End Date "07/08/2010"

corresponding as desired. But the moment I enter the start date and end date as
as

Start date "04/01/2010"
End Date "04/30/2010" which is a 1 Month period and then add 1 Month to the code
the corresponding dates are

Start date "05/01/2010"
End Date "05/30/2010"

Start date "06/01/2010"
End Date "06/30/2010" [ Even though it has 31 days in June, then from Feb 2011 its like

Start date 01/01/2011
End Date 01/30/2011

Start date 02/01/2011
End date 02/28/2011

Start date 03/01/2011
Start date 03/28/2011

everything ends on the 28th

Can any one let me know why in my first condition the 31st day was being taken care of and in the next condition I am not getting the same output.

Details 04/01/2011 04/28/2011

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