You can use Joda-Time for this.
It provides the class Interval
which specifies a start and end instants and can check for overlaps with overlaps(Interval)
.
Something like
DateTime now = DateTime.now();
DateTime start1 = now;
DateTime end1 = now.plusMinutes(1);
DateTime start2 = now.plusSeconds(50);
DateTime end2 = now.plusMinutes(2);
Interval interval = new Interval( start1, end1 );
Interval interval2 = new Interval( start2, end2 );
System.out.println( interval.overlaps( interval2 ) );
prints
true
since the end of the first interval falls between the start and end of the second interval.