从Java 9开始，我们可以通过引入四个核心接口（Publisher，Subscriber，Subscription，Processor和一个具体的类）来创建R eactive Streams：实现Publisher 接口的SubmissionPublisher 。每个接口都扮演着不同的角色，这与响应 流的原理相对应。我们可以使用SubmissionPublisher 类的Submit()方法将提供的项目发布给每个订阅者。
语法
public class SubmissionPublisher<T> extends Object implements Flow.Publisher<T>, AutoCloseable
在下面的示例中，我们可以实现SubmissionPublisher类
import java.util.concurrent.Flow.Subscriber;
import java.util.concurrent.Flow.Subscription;
import java.util.concurrent.SubmissionPublisher;
class MySubscriber<T> implements Subscriber<T> {
private Subscription subscription;
private String name;
public MySubscriber(String name) {
this.name = name;
}
@Override public void onComplete() {
System.out.println(name + ": onComplete");
}
@Override public void onError(Throwable t) {
System.out.println(name + ": onError");
t.printStackTrace();
}
@Override public void onNext(T msg) {
System.out.println(name + ": " + msg.toString() + " received in onNext");
subscription.request(1);
}
@Override public void onSubscribe(Subscription subscription) {
System.out.println(name + ": onSubscribe");
this.subscription = subscription;
subscription.request(1);
}
}// Main classpublic class FlowTest {
public static void main(String args[]) {
SubmissionPublisher<String> publisher = new SubmissionPublisher<>();
MySubscriber<String> subscriber = new MySubscriber<>("Mine");
MySubscriber<String> subscriberYours = new MySubscriber<>("Yours");
MySubscriber<String> subscriberHis = new MySubscriber<>("His");
MySubscriber<String> subscriberHers = new MySubscriber<>("Her");
publisher.subscribe(subscriber);
publisher.subscribe(subscriberYours);
publisher.subscribe(subscriberHis);
publisher.subscribe(subscriberHers);
publisher.submit("One");
publisher.submit("Two");
publisher.submit("Three");
publisher.submit("Four");
publisher.submit("Five");
try {
Thread.sleep(1000);
} catch(InterruptedException e) {
e.printStackTrace();
}
publisher.close();
}
}输出结果
Yours: onSubscribe His: onSubscribe Mine: onSubscribe His: One received in onNext Yours: One received in onNext Mine: One received in onNext Yours: Two received in onNext His: Two received in onNext Yours: Three received in onNext Mine: Two received in onNext Yours: Four received in onNext His: Three received in onNext Yours: Five received in onNext Mine: Three received in onNext Her: onSubscribe His: Four received in onNext Her: One received in onNext Mine: Four received in onNext Her: Two received in onNext His: Five received in onNext Her: Three received in onNext Mine: Five received in onNext Her: Four received in onNext Her: Five received in onNext Yours: onComplete His: onComplete Mine: onComplete Her: onComplete