The java.util.concurrent.ConcurrentLinkedDeque.peekFirst() is an in-built method in Java which
retrieves the first element of this deque without removing it. The function returns NULL if the deque is empty.
Parameters: This function does not accepts any parameter.
Return Values: The function returns the first element present in this deque and returns NULL when the deque is empty.
Below programs illustrate the peekFirst() method:
Program 1: This program involves deque with Integer elements.
Elements inthe LinkedDeque: [76, 55, 110, 12] First Element inthe LinkedDeque: 76
Program 2: This program involves deque with String elements.
Elements inthe LinkedDeque: [Geeks, GeeksforGeeks, Gfg, GFG] First Element inthe LinkedDeque: Geeks
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