The peekFirst() method of LinkedBlockingDeque returns the front element in the Deque container, but does not deletes it. It returns null if the container is empty.
public E peekFirst()
Parameters: This method does not accept any parameters.
Returns: This method returns front element in the Deque container if the container is not empty. It returns null if the container is empty.
Below programs illustrate peekFirst() method of LinkedBlockingDeque:
Linked Blocking Deque: [74381793, 5278367, 35658786, 7855642] Front element in Deque: 74381793
Linked Blocking Deque: [7855642, 35658786, 5278367, 74381793] Front element in Deque: null
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