Java / Concurrent collections
Explain SynchronousQueue in Java concurrent collections.
The SynchronousQueue class implements the BlockingQueue interface introduced in Java 1.5.
SynchronousQueue is a blocking queue in which each insert operation must wait for a corresponding remove operation by another thread, and vice versa. A synchronous queue does not have any internal capacity.
The peek operation cannot be performed at a synchronous queue because an element is only present when you try to remove it; you cannot insert an element (using any method) unless another thread is trying to remove it; you cannot iterate as there is nothing to iterate. The head of the queue is the element that the first queued inserting thread is trying to add to the queue; if there is no such queued thread then no element is available for removal and poll() will return null. This queue does not permit null elements.
This class supports an optional fairness policy for ordering waiting producer and consumer threads. A queue constructed with fairness set to true grants threads access in FIFO order.
They are well suited for handoff designs, in which an object running in one thread must sync up with an object running in another thread in order to hand it some information, event, or task.
Dogecoin
! Earn free bitcoins up to $250 now by signing up.
Earn bitcoins upto $250 (free), invest in other Cryptocurrencies when you signup with blockfi.
Use the referral link: Signup now and earn!

Using BlockFi, don't just buy crypto - start earning on it. Open an interest account with up to 8.6% APY, trade currencies, or borrow money without selling your assets.

Join CoinBase
! We'll both receive $10 in free Bitcoin when they buy or sell their first $100 on Coinbase! Available in India also.
Use the referral Join coinbase!

Invest now!!! Get Free equity stock (US, UK only)!
Use Robinhood app to invest in stocks. It is safe and secure. Use the Referral link to claim your free stock when you sign up!.
The Robinhood app makes it easy to trade stocks, crypto and more.

Webull
! Receive free stock by signing up using the link: Webull signup.
More Related questions...