The
addFirst(E e) method of
BlockingDeque inserts the element passed in the parameter to the front of the Deque if there is space. If the BlockingDeque is capacity restricted and no space is left for insertion, it returns an
IllegalStateException.
Syntax:
public void addFirst(E e)
Parameters: This method accepts a mandatory parameter
e which is the element to be inserted in the front of the BlockingDeque.
Returns: This method does not returns anything.
Exception:
- IllegalStateException: if the element cannot be added at this time due to capacity restrictions
- NullPointerException: if the specified element is null
Note: The addFirst() method of
BlockingDeque has been inherited from the
LinkedBlockingDeque class in Java.
Below programs illustrate addFirst() method of BlockingQueue:
Program 1:
Output:
Blocking Deque: [74381793, 5278367, 35658786, 7855642]
Program 2:
Output:
Exception in thread "main" java.lang.IllegalStateException: Deque full
at java.util.concurrent.LinkedBlockingDeque.addFirst(LinkedBlockingDeque.java:326)
at GFG.main(GFG.java:24)
Program 3:
