我们如何在Java 9中使用Publisher-Subscriber来实现Flow API？
FlowAPI(java.util.concurrent.Flow)已在Java9中引入。它有助于了解Publisher 和Subscriber 接口交互以执行所需操作的不同方式。
FlowAPI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FlowAPI。
示例
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