Stack isEmpty() method in Java with Example

Last Updated : 24 Dec, 2018

The Java.util.Stack.isEmpty() method in Java is used to check and verify if a Stack is empty or not. It returns True if the Stack is empty else it returns False.

Syntax:

Stack.isEmpty()

Parameters: This method does not take any parameter.

Return Value: This function returns True if the Stackis empty else it returns False.

Below programs illustrate the Java.util.Stack.isEmpty() method:

Program 1:

// Java code to illustrate isEmpty() 
import java.util.*; 
  
public class StackDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty Stack 
        Stack<String> stack = new Stack<String>(); 
  
        // Use add() method to add elements into the Stack 
        stack.add("Welcome"); 
        stack.add("To"); 
        stack.add("Geeks"); 
        stack.add("4"); 
        stack.add("Geeks"); 
  
        // Displaying the Stack 
        System.out.println("Stack:  " + stack); 
  
        // Verifying if the Stack is empty or not 
        System.out.println("Is the Stack empty? "
                           + stack.isEmpty()); 
  
        // Clearing the Stack 
        stack.clear(); 
  
        // Displaying the Stack 
        System.out.println("Stack after clear(): "
                           + stack); 
  
        // Verifying if the Stack is empty or not 
        System.out.println("Is the Stack empty? "
                           + stack.isEmpty()); 
    } 
} 

Output:

Stack:  [Welcome, To, Geeks, 4, Geeks]
Is the Stack empty? false
Stack after clear(): []
Is the Stack empty? true

Program 2:

// Java code to illustrate isEmpty() 
import java.util.*; 
  
public class StackDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty Stack 
        Stack<Integer> stack = new Stack<Integer>(); 
  
        // Displaying the Stack 
        System.out.println("Stack:  " + stack); 
  
        // Verifying if the Stack is empty or not 
        System.out.println("Is the Stack empty? "
                           + stack.isEmpty()); 
    } 
} 

Output:

Stack:  []
Is the Stack empty? true

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