Welcome to the Ranch.
There is no built in date chooser component in Swing. Probably you are using something like
JCalendar
Irrespective of what you use, the chooser is designed to do exactly what it says, viz. choose dates.
To compute the number of days, check out
https://coderanch.com/t/543495/java/java/Number-days-dates
kevinj canlas wrote:help me plssssss
Please
UseRealWords