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Java TreeSet isEmpty() Method with Example

TreeSet Class isEmpty() method: Here, we are going to learn about the isEmpty() method of TreeSet Class with its syntax and example.
Submitted by Preeti Jain, on February 20, 2020

TreeSet Class isEmpty() method

• isEmpty() method is available in java.util package.
• isEmpty() method is used to check whether this TreeSet is empty or not.
• isEmpty() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• isEmpty() method does not throw an exception at the time of checking the empty status of this TreeSet.

Syntax:

    public boolean isEmpty();

Parameter(s):

• It does not accept any parameter.

Return value:

The return type of the method is boolean, it returns true when this TreeSet is empty otherwise it returns false.

Example:

// Java program to demonstrate the example 
// of boolean isEmpty() method of TreeSet 

import java.util.*;

public class IsEmptyOfTreeSet {
    public static void main(String[] args) {
        // Instantiates a TreeSet object
        TreeSet < String > tree_set = new TreeSet < String > ();

        // By using add() method is to add
        // the given object of this
        // TreeSet 
        tree_set.add("C");
        tree_set.add("C++");
        tree_set.add("JAVA");
        tree_set.add("PHP");
        tree_set.add("SFDC");

        // Display TreeSet
        System.out.println("TreeSet: " + tree_set);

        // By using isEmpty() method is
        // to check whether this TreeMap is
        // empty or not
        boolean status = tree_set.isEmpty();

        // Display status
        System.out.println("tree_set.isEmpty(): " + status);
    }
}

Output

TreeSet: [C, C++, JAVA, PHP, SFDC]
tree_set.isEmpty(): false