5. Barriers
Barriers serve as a synchronization tool in multi-threaded programming. They act as checkpoints, ensuring that all participating threads pause at a specific point and only proceed once every thread has reached this point. Upon all threads arriving at the barrier, they are collectively released to continue their subsequent tasks. This mechanism is essential for coordinating threads in scenarios where simultaneous progress or data consistency is critical.
import java.util.concurrent.CyclicBarrier;
class Solution {
static CyclicBarrier barrier = new CyclicBarrier(2, () ->
System.out.println(
"All threads have reached the barrier. Continue execution."
)
);
public static void main(String[] args) {
Thread t1 = new Thread(Solution::work);
Thread t2 = new Thread(Solution::work);
// Start both threads.
t1.start();
t2.start();
}
static void work() {
System.out.println(
"Thread " +
Thread.currentThread().getName() +
" is waiting at the barrier"
);
try {
barrier.await(); // Wait for the specified number of threads (2 in this case) to reach the barrier.
System.out.println(
"Thread " + Thread.currentThread().getName() + " is released"
);
} catch (Exception e) {
// Handle exceptions, if any.
}
}
}
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