The Java.util.Stack.insertElementAt(element, index) method is used to insert a particular element at the specified index of the Stack. Both the element and the position is passed as the parameters. If an element is inserted at a specified index, then all the elements are pushed upward by one and hence the capacity is increased, creating a space for the new element.
Syntax:
Stack.insertElementAt()
Parameters: The method accepts two parameters:
- element: This is element required to be inserted into the Stack.
- index: This is of integer type and refers to the position where the new element is to be inserted.
Return Value: The method does not return anything.
Exception: The method throws ArrayIndexOutOfBoundsException if the index is an invalid number.
Below programs illustrate the Java.util.Stack.insertElementAt() method:
Program 1: Adding String elements into the Stack.
Java
// Java code to illustrate insertElementAt()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); // Inserting element at 3rd position stack.insertElementAt("Hello", 2); // Inserting element at last position stack.insertElementAt("World", 6); // Displaying the final Stack System.out.println("The final Stack is " + stack); }} |
Output:
Stack: [Welcome, To, Geeks, 4, Geeks] The final Stack is [Welcome, To, Hello, Geeks, 4, Geeks, World]
Program 2: Adding Integer elements into the Stack.
Java
// Java code to illustrate insertElementAt()import java.util.*;public class StackDemo { public static void main(String args[]) { // Creating an empty Stack Stack<Integer> stack = new Stack<Integer>(); // Use add() method to add elements into the Stack stack.add(10); stack.add(20); stack.add(30); stack.add(40); stack.add(50); // Displaying the Stack System.out.println("Stack: " + stack); // Inserting element at 1st position stack.insertElementAt(100, 0); // Inserting element at fifth position stack.insertElementAt(200, 4); // Displaying the final Stack System.out.println("The final Stack is " + stack); }} |
Output:
Stack: [10, 20, 30, 40, 50] The final Stack is [100, 10, 20, 30, 200, 40, 50]
