Collection in Java represents a single unit of the group. Using Java collection you can perform all the operations on the data like searching, sorting, inserting, manipulation, deletion, etc.

Do you need to know how to sort Java objects in a collection, array, or map? Here's how to use the Comparable and Comparator interfaces and avoid ClassCastExceptions.

Sort One of the most common needs with collections is sorting. Java has long had a built-in Arrays.sort method, and Collections.sort allows for sorting by natural order or using a custom comparator.