java.util.TreeSet.isEmpty() Method

Description

The isEmpty() method is used to return true if this set contains no elements.

Declaration

Following is the declaration for java.util.TreeSet.isEmpty() method.

public boolean isEmpty()

Parameters

• NA

Return Value

The method call returns true if this set contains no elements.

Exception

• NA

Example

The following example shows the usage of java.util.TreeSet.isEmpty() method.

package com.tutorialspoint;

import java.util.TreeSet;

public class TreeSetDemo {
   public static void main(String[] args) {
     // creating a TreeSet 
     TreeSet <Integer>treeadd = new TreeSet<Integer>();
     
     // checking tree set
     System.out.println("Is the tree set empty: "+treeadd.isEmpty()); 
     
     // adding elements in the tree set
     System.out.println("Adding elements in the tree set"); 
     treeadd.add(12);
     treeadd.add(11);
     treeadd.add(16);
     treeadd.add(15);
     
     // checking tree set again
     System.out.println("Is the tree set empty: "+treeadd.isEmpty());  
   }     
}

Let us compile and run the above program, this will produce the following result.

Is the tree set empty: true
Adding elements in the tree set
Is the tree set empty: false