Best Practice in handling comparator

Question

How to handle null objects, which comes in compareTo method. This always causes nullpointer exception. What a is best way to solve this issue.

Answer 1

public int compareTo(Object to) {
  if (to == null) return Integer.MIN_VALUE;
  // Now knowing it's not null, continue as before
}

Answer 2

You can check the object before you call "compareTo" method.

like this:

if(obj != null){

  //TODO  

}

Answer 3

From the fine documentation on Comparable :

Note that null is not an instance of any class, and e.compareTo(null) should throw a NullPointerException even though e.equals(null) returns false.

Don't put null in a sorted collection if you don't want to handle NullPointerExceptions.