Java BlockingDeque is an interface in Java's java.util.concurrent package that represents a thread-safe, blocking deque (double-ended queue). It allows elements to be added and removed from both ends of the queue, with blocking operations for adding or removing elements when the deque is full or empty. Introduced in Java 2004 with Java 5, BlockingDeque is useful for implementing producer-consumer patterns and controlling concurrent access to resources in multi-threaded applications.

https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/BlockingDeque.html