Example of using the countdownlatch class with concurrent Java threads
- 2020-04-01 02:49:03
- OfStack
package com.yao;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class CountDownLatchTest {
public static class ComponentThread implements Runnable {
//counter
CountDownLatch latch;
//Component ID
int ID;
//A constructor
public ComponentThread(CountDownLatch latch, int ID) {
this.latch = latch;
this.ID = ID;
}
public void run() {
//Initialize component
System.out.println("Initializing component " + ID);
try {
Thread.sleep(500 * ID);
} catch (InterruptedException e) {
}
System.out.println("Component " + ID + " initialized!");
//Subtract one from the counter
latch.countDown();
}
}
public static void startServer() throws Exception {
System.out.println("Server is starting.");
//Initializes an CountDownLatch with an initial value of 3
CountDownLatch latch = new CountDownLatch(3);
//Start three threads to start three components
ExecutorService service = Executors.newCachedThreadPool();
service.submit(new ComponentThread(latch, 1));
service.submit(new ComponentThread(latch, 2));
service.submit(new ComponentThread(latch, 3));
service.shutdown();
//Wait for the initialization of all three components to complete
latch.await();
//When all three required components are complete, Server can proceed
System.out.println("Server is up!");
}
public static void main(String[] args) throws Exception {
CountDownLatchTest.startServer();
}
}