Question

Possible Duplicate:
Java: What is the difference between implementing Comparable and Comparator?

Difference between comparable interface and comparator interface and where to use?example?

Answer 1

Comparable makes an object intrinsically comparable to other objects.

Comparator allows to implement external comparison logic, which can be applied to objects that are not Comparable, or that require different logic from their default comparison logic.

For example, you have Collections.sort(list), which can sort only lists of objects that implement Comparable, while there is another method – Collections.sort(list, comparator), by which you can sort any list.