getFirst : Retrieves the first element of this deque

E getFirst()

Retrieves, but does not remove, the first element of this deque.

import java.util.*;

class DequeGetFirst{
 public static void main(String args[]){
  Deque<Integer> myDeque = new LinkedList<Integer> ();
  
  /* Add Elements to the myDeque */
  myDeque.add(10);
  myDeque.add(20);
  myDeque.add(30);
  myDeque.add(40);
  
  System.out.println("Elements in the myDeque are " +myDeque);
  
  System.out.println("\nRetrieving the First Element Of the Deque " + myDeque.getFirst());
  System.out.println("Elements in the myDeque are " +myDeque);
  
  System.out.println("\nRetrieving the First Element Of the Deque " + myDeque.getFirst());
  System.out.println("Elements in the myDeque are " +myDeque);
  
 }
}

Output

Elements in the myDeque are [10, 20, 30, 40]

Retrieving the First Element Of the Deque 10
Elements in the myDeque are [10, 20, 30, 40]

Retrieving the First Element Of the Deque 10
Elements in the myDeque are [10, 20, 30, 40]

1. throws NoSuchElementException if this deque is empty

import java.util.*;

class DequeGetFirstNoSuch{
 public static void main(String args[]){
  Deque<Integer> myDeque = new LinkedList<Integer> ();

  System.out.println("Elements in the myDeque are " +myDeque);
  
  System.out.println("\nRetrieving the First Element Of the Deque " + myDeque.getFirst());
  System.out.println("Elements in the myDeque are " +myDeque);
 }
}

Output

Elements in the myDeque are []
Exception in thread "main" java.util.NoSuchElementException
        at java.util.LinkedList.getFirst(LinkedList.java:242)
        at DequeGetFirstNull.main(DequeGetFirstNull.java:12)

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