I need help with java. Need to calculate some data.

So I have two questions i'm trying to answer and calculate.
1. What is the date of birth for your pet?
2. When was it vaccinated?

The answers should be dates. Their might be a few more questions.

The calculation should give you and answer saying yes your in compliance or
no. Can I do something that specific before I waste my time trying to
figure out the code for it?

Also, if this can be done with java, is there a site where I can figure the code out or can someone assist me with the code? Any and all help appreciated.

Thanks

Cindy