Скачать или смотреть Java Programming: Simplifying Data Storage and Manipulation with Sets | Quick Guide

A Set in Java is a collection that contains no duplicate elements. It is an unordered data structure, and elements have no specific order. The java.util.Set interface is implemented by several classes, such as HashSet, LinkedHashSet, and TreeSet.

How to use it?

To use a Set, import the java.util package.
Create an instance of a Set implementation, like HashSet.
Use the add() method to insert elements into the Set.
Use the contains() method to check if the Set contains a specific element.
Iterate through the Set using a for-each loop or an iterator.

In this example, we create a Set of strings using the HashSet implementation. We add elements to the Set and print it out, which will only show apple, banana, and orange since apple is a duplicate and not added. We then remove banana from the Set and check if orange is present using the contains() method.

https://docs.oracle.com/javase/7/docs...