Simple Java HashSet example
- /*
- Simple Java HashSet example
- This simple Java Example shows how to use Java HashSet. It also describes how to
- add something to HashSet object using add method.
- */
- import java.util.HashSet;
- public class SimpleHashSetExample {
- public static void main(String[] args) {
- //create object of HashSet
- HashSet hSet = new HashSet();
- /*
- Add an Object to HashSet using
- boolean add(Object obj) method of Java HashSet class.
- This method adds an element to HashSet if it is not already present in HashSet.
- It returns true if the element was added to HashSet, false otherwise.
- */
- hSet.add(new Integer("1"));
- hSet.add(new Integer("2"));
- hSet.add(new Integer("3"));
- /*
- Please note that add method accepts Objects. Java Primitive values CAN NOT
- be added directly to HashSet. It must be converted to corrosponding
- wrapper class first.
- */
- System.out.println("HashSet contains.." + hSet);
- }
- }
- /*
- Output of the program would be
- HashSet contains..[3, 2, 1]
- */
