Check if two date periods overlap [duplicate]

• I have two date ranges, (start1,end1):::>>date1 && (start2,end2):::>>date2 .

• I want to check if the two dates isOverLaped.

• My flow chart I assume "<>=" operators is valid for comparing.

  boolean isOverLaped(Date start1,Date end1,Date start2,Date end2) {
      if (start1>=end2 && end2>=start2 && start2>=end2) {
          return false;
      } else {
          return true;
      }
  }
  

• Any Suggestion will be appreciated.

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.

boolean overlap(Date start1, Date end1, Date start2, Date end2){
    return start1.getTime() <= end2.getTime() && start2.getTime() <= end1.getTime(); 
}