CountDownLatch and CyclicBarrier both used in multithreading environment and they both are part of.
As per Java Doc −
CountDownLatch − A synchronization aid that allows one or more threads to wait until a set of operations being performed in other threads completes.
CyclicBarrier − A synchronization aid that allows a set of threads to all wait for each other to reach a common barrier point.
| Sr. No. | Key | CyclicBarrier | CountDownLatch |
|---|---|---|---|
| 1 | Basic | A synchronization aid that allows a set of threads to all wait for each other to reach a common barrier point. | A synchronization aid that allows one or more threads to wait until a set of operations being performed in other threads completes. |
| 2 | Ruunable | It has a constructor where Runnable can be provided. | It don’t have such constructor |
| 3 | Thread /Task | It maintains a count of threads | It maintains a count of tasks |
| 4. | A dvanceable | It is not advancable | It is advancable. |
| 5 | Exception | If one thread is interrupted while waiting then all other waiting threads will throw B rokenBarrierException | Only current thread will throw InterruptedException. It will not impact other threads |
Example of CyclicBarrier
public class Main {
public static void main(String args[]) throws InterruptedException {
ExecutorService executors = Executors.newFixedThreadPool(4);
CyclicBarrier cyclicBarrier = new CyclicBarrier(5);
executors.submit(new Service1(cyclicBarrier));
executors.submit(new Service1(cyclicBarrier));
executors.submit(new Service2(cyclicBarrier));
executors.submit(new Service2(cyclicBarrier));
executors.submit(new Service2(cyclicBarrier));
Thread.sleep(3000);
System.out.println("Done");
}
}
import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.CyclicBarrier;
public class Service1 implements Runnable {
CyclicBarrier cyclicBarrier;
public Service1(CyclicBarrier cyclicBarrier) {
super();
this.cyclicBarrier = cyclicBarrier;
}
@Override
public void run() {
System.out.println("Services1" + cyclicBarrier.getNumberWaiting());
while (true) {
try {
cyclicBarrier.await();
} catch (InterruptedException | BrokenBarrierException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.CyclicBarrier;
public class Service2 implements Runnable {
CyclicBarrier cyclicBarrier;
public Service2(CyclicBarrier cyclicBarrier) {
super();
this.cyclicBarrier = cyclicBarrier;
}
@Override
public void run() {
System.out.println("Services2" + cyclicBarrier.getNumberWaiting());
while (true) {
try {
cyclicBarrier.await();
} catch (InterruptedException | BrokenBarrierException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}Example of CountDownLatch
public class Main {
public static void main(String args[]) throws InterruptedException {
ExecutorService executors = Executors.newFixedThreadPool(4);
CountDownLatch latch= new CountDownLatch(2);
executors.submit(new Service1(latch));
executors.submit(new Service2(latch));
latch.await();
System.out.println("Done");
}
}
import java.util.concurrent.CountDownLatch;
public class Service1 implements Runnable {
CountDownLatch latch;
public Service1(CountDownLatch latch) {
super();
this.latch = latch;
}
@Override
public void run() {
try {
Thread.sleep(20000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
latch.countDown();
System.out.println("Services2"+latch.getCount());
}
}
import java.util.concurrent.CountDownLatch;
public class Service2 implements Runnable {
CountDownLatch latch;
public Service2(CountDownLatch latch) {
super();
this.latch = latch;
}
@Override
public void run() {
try {
Thread.sleep(20000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
latch.countDown();
System.out.println("Services2"+latch.getCount());
}
}