Skip to content
Related Articles

Related Articles

Stack push() Method in Java

View Discussion
Improve Article
Save Article
  • Difficulty Level : Basic
  • Last Updated : 10 Jun, 2022

Java.util.Stack.push(E element) method is used to push an element into the Stack. The element gets pushed onto the top of the Stack.

Syntax:

STACK.push(E element)

Parameters: The method accepts one parameter element of type Stack and refers to the element to be pushed into the stack.

Return Value: The method returns the argument passed.  It also accepts the null value unlike ArrayDeque.push() which throws java.lang.NullPointerException on doing the same.

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

Program 1: Adding String elements into the Stack. 

Java




// Java Code to illustrate push() Method
 
import java.util.*;
 
// Main class
public class StackDemo {
 
    // Main driver method
    public static void main(String args[])
    {
        // Creating an empty Stack
        Stack& lt;
        String& gt;
        STACK = new Stack& lt;
        String& gt;
        ();
 
        // Adding elements into the stack
        // using push() method
        STACK.push(" Welcome & quot;);
        STACK.push(" To & quot;);
        STACK.push(" Geeks & quot;);
        STACK.push(" For & quot;);
        STACK.push(" Geeks & quot;);
 
        // Displaying the Stack
        System.out.println(" Initial Stack
                           : "
                           + STACK);
 
        // Pushing elements into the stack
        STACK.push(" Hello & quot;);
        STACK.push(" World & quot;);
 
        // Displaying the final Stack
        System.out.println(" Final Stack
                           : "
                           + STACK);
    }
}

Output:

Initial Stack: [Welcome, To, Geeks, For, Geeks]
Final Stack: [Welcome, To, Geeks, For, Geeks, Hello, World]

Program 2: Adding Integer elements into the Stack. 

Java




// Java code to illustrate push() method
import java.util.*;
 
public class StackDemo {
    public static void main(String args[])
    {
        // Creating an empty Stack
        Stack<Integer> STACK = new Stack<Integer>();
 
        // Use push() to add elements into the Stack
        STACK.push(10);
        STACK.push(15);
        STACK.push(30);
        STACK.push(20);
        STACK.push(5);
        STACK.push(null);
 
        // Displaying the Stack
        System.out.println("Initial Stack: " + STACK);
 
        // Pushing elements into the Stack
        STACK.push(1254);
        STACK.push(4521);
 
        // Displaying the final Stack
        System.out.println("Final Stack: " + STACK);
    }
}

Output:

Initial Stack: [10, 15, 30, 20, 5]
Final Stack: [10, 15, 30, 20, 5, 1254, 4521]

My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!