Flow API(java.util.concurrent.Flow)已在Java 9中引入。它有助于了解Publisher 和S ubscriber 接口交互以执行所需操作的不同方式。
Flow AP I由发布者,订阅者,订阅和处理器接口组成,它们可以基于反应式流规范。
在下面的示例中,我们可以使用Publisher-Subscriber接口来实现Flow API。
import java.util.concurrent.Flow.Publisher; import java.util.concurrent.Flow.Subscriber; import java.util.concurrent.Flow.Subscription; public class FlowAPITest { public static void main(String args[]) { Publisher<Integer> publisherSync = new Publisher<Integer>() { // Create publisher @Override public void subscribe(Subscriber<? super Integer> subscriber) { for(int i = 0; i < 10; i++) { System.out.println(Thread.currentThread().getName() + " | Publishing = " + i); subscriber.onNext(i); } subscriber.onComplete(); } }; Subscriber<Integer> subscriberSync = new Subscriber<Integer>() { // Create subscriber @Override public void onSubscribe(Subscription subscription) { } @Override public void onNext(Integer item) { System.out.println(Thread.currentThread().getName() + " | Received = " + item); try { Thread.sleep(100); } catch(InterruptedException e) { e.printStackTrace(); } } @Override public void onError(Throwable throwable) { } @Override public void onComplete() { } }; publisherSync.subscribe(subscriberSync); } }
输出结果
main | Publishing = 0 main | Received = 0 main | Publishing = 1 main | Received = 1 main | Publishing = 2 main | Received = 2 main | Publishing = 3 main | Received = 3 main | Publishing = 4 main | Received = 4 main | Publishing = 5 main | Received = 5 main | Publishing = 6 main | Received = 6 main | Publishing = 7 main | Received = 7 main | Publishing = 8 main | Received = 8 main | Publishing = 9 main | Received = 9