Optimized way to calculate age from timestamp,
the idea is not to use date() call at all if possible.

Computes the difference between two dates in seconds

Date Parse

A handy class I use all the time to encapsulate the idea of whether two events coincide. For example, given a time period representing a shift, and a list of time periods representing transactions or sessions or whatever, find which ones are either totally or partially within the time period. This class make it a bit easier.

Compare two dates in Java.

If you only want to compare yyyy-mm-dd you can use the java.sql.Date class, the valueOf method does the trick. It's perfectly safe as the sql Date class is a subclass of the Date class.

Check out the docs here for more detail.

enjoy

How Long Has It Been Since a Certain Date?

daysBeteenDates will calculate the number of days between 2 dates in the form of 'YYYY-MM-DD'.