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BlockingDeque offerFirst() method in Java with Examples

Last Updated : 12 Jul, 2025

The offerFirst(E e) method of BlockingDeque inserts the element passed in the parameter at the front of the Deque container. If the container's capacity has exceeded, then it does not returns an exception as in case of add() and addFirst() function.

Syntax: 

public boolean offerFirst(E e)

Parameters: This method accepts a mandatory parameter e which is the element to be inserted at the front of the BlockingDeque. 

Returns: This method returns true if the element has been inserted, else it returns false. 

Note: The offerFirst() method of BlockingDeque has been inherited from the LinkedBlockingDeque class in Java. 

Below programs illustrate offerFirst() method of LinkedBlockingDeque:

Program 1:  


Output: 
The element 10 cannot be inserted as capacity is full
Blocking Deque: [74381793, 5278367, 35658786, 7855642]

 

Program 2: 


Output: 
The element 'hii' cannot be inserted as capacity is full
Blocking Deque: [richik, geeks, gopu, abc]

 

Reference: https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/BlockingDeque.html#offerFirst(E)
 

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