What is the use of BlockingQueue?

What is the use of BlockingQueue?

BlockingQueue , represents a queue which is thread safe to put elements into, and take elements out of from. In other words, multiple threads can be inserting and taking elements concurrently from a Java BlockingQueue , without any concurrency issues arising.

What is BlockingQueue?

A blocking queue is a queue that blocks when you try to dequeue from it and the queue is empty, or if you try to enqueue items to it and the queue is already full. A thread trying to dequeue from an empty queue is blocked until some other thread inserts an item into the queue.

Is ConcurrentLinkedQueue thread safe?

Class ConcurrentLinkedQueue An unbounded thread-safe queue based on linked nodes. A ConcurrentLinkedQueue is an appropriate choice when many threads will share access to a common collection. Like most other concurrent collection implementations, this class does not permit the use of null elements.

What is countDown latch?

CountDownLatch is a concurrency construct that allows one or more threads to wait for a given set of operations to complete. A CountDownLatch is initialized with a given count. This count is decremented by calls to the countDown() method. Threads waiting for this count to reach zero can call one of the await() methods.

What is BlockingQueue how can we implement producer consumer problem using blocking queue?

BlockingQueue:

1. If a producer thread tries to put an element in a full BlockingQueue, it gets blocked and stays blocked until a consumer removes an element.
2. Similarly, if a consumer thread tries to take an element from an empty BlockingQueue, it gets blocked and remains blocked until a producer adds an element.

What is the max capacity of a Java BlockingQueue?

10
Here we have a blockingQueue that has a capacity equal to 10. It means that when a producer tries to add an element to an already full queue, depending on a method that was used to add it (offer(), add() or put()), it will block until space for inserting object becomes available. Otherwise, the operations will fail.

Which is an example of a blocking queue?

For example, if we want to delete an element from an empty queue, then the blocking queue allows the delete operation to wait until the queue contains some elements to be deleted. Since BlockingQueue is an interface, we cannot provide the direct implementation of it.

What do you need to know about BlockingQueue in Java?

All Known Implementing Classes: A Queue that additionally supports operations that wait for the queue to become non-empty when retrieving an element, and wait for space to become available in the queue when storing an element.

Is there a way to close a BlockingQueue?

A BlockingQueue does not intrinsically support any kind of “close” or “shutdown” operation to indicate that no more items will be added. The needs and usage of such features tend to be implementation-dependent.

What should the capacity of BlockingQueue be set to?

The Capacity of blockingQueue will be set to Integer.MAX_VALUE. All operations that add an element to the unbounded queue will never block, thus it could grow to a very large size.