The java.util.ConcurrentLinkedDeque.peek() method in Java is used to retrieve or fetch the element at the head of the Deque. The element retrieved does not get deleted or removed from the Deque instead the method just returns it. If no element is present in the deque then Null is returned.
Syntax:
Array_Deque.peek()
Parameters: The method does not take any parameter.
Return Value: The method returns the element at the head of the Deque.
Below programs illustrate the Java.util.ConcurrentLinkedDeque.peek() method:
Program 1:
Output:
Initial ConcurrentLinkedDeque: [Welcome, To, Geeks, 4, Geeks]
The element at head is: Welcome
Final ConcurrentLinkedDeque: [Welcome, To, Geeks, 4, Geeks]
Program 2:
Output:
Initial ConcurrentLinkedDeque: [10, 15, 30, 20, 5]
The element at head is: 10
Final ConcurrentLinkedDeque: [10, 15, 30, 20, 5]
Program 3: For an empty deque:
