Understanding Java’s Synchronization Tools: CountDownLatch, CyclicBarrier, and Semaphore

source: opensourceforgeeks.blogspot.com

When working with multiple threads in Java, we often need ways to coordinate their actions. Java provides several useful tools for this purpose in the java.util.concurrent package. In this article, we'll explore three important synchronization tools: CountDownLatch, CyclicBarrier, and Semaphore. We'll see how they work, when to use them, and look at practical code examples.

CountDownLatch: Wait Until a Set of Operations is Complete

What is CountDownLatch?

A CountDownLatch is like a counter that starts at a number you choose. Threads can decrease this counter by calling the countDown() method. Other threads can wait for the counter to reach zero by calling the await() method. Once the counter reaches zero, all waiting threads are released.

Key features of CountDownLatch:

1. One-time use: Once the count reaches zero, it cannot be reset or reused.
2. Wait for completion: Good for waiting until multiple operations finish.
3. Simple to use: Has only a few main methods.

When to use CountDownLatch:

• When you need to…