Java FAQ: Top Questions

Comparable and Comparator are interfaces in Java used for sorting objects, defined in java.lang and java.util , respectively.

• Comparable:
  • Implemented by a class to define its natural ordering (e.g., String , Integer ).
  • Has one method: compareTo(T o) .
  • Used by Collections.sort or Arrays.sort .
• Comparator:
  • A separate class or lambda for custom sorting.
  • Has method: compare(T o1, T o2) .
  • Provides flexibility for multiple sorting criteria without modifying the class.