The Java.util.ArrayDeque.offerFirst(Object element) method in Java is used to add a specific element at the front of the Deque. The function is similar to the addFirst() method of ArrayDeque in Java.
Parameters: The parameter element is of the type ArrayDeque and refers to the element to be added at the front of the Deque.
Return Value: The function returns True if the element is successfully added into the deque else it returns false.
Exceptions: The method throws NullPointerException if the passed parameter is NULL.
Below programs illustrate the Java.util.ArrayDeque.offerFirst() method:
Program 1: Adding String elements into the Deque.
Initial Deque: [Welcome, To, Geeks, 4, Geeks] Final Deque: [Hello, World, Welcome, To, Geeks, 4, Geeks]
Program 2: Adding Integer elements into the Deque.
Initial Deque: [10, 15, 30, 20, 5] Final Deque: [2458, 1658, 10, 15, 30, 20, 5]
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