examples/reactor/src/main/java/org/apache/qpid/proton/example/reactor/GoodbyeWorld.java

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 * to you under the Apache License, Version 2.0 (the
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package org.apache.qpid.proton.example.reactor;

import java.io.IOException;

import org.apache.qpid.proton.Proton;
import org.apache.qpid.proton.engine.BaseHandler;
import org.apache.qpid.proton.engine.Event;
import org.apache.qpid.proton.reactor.Reactor;

// So far the reactive hello-world doesn't look too different from a
// regular old non-reactive hello-world. The onReactorInit method can
// be used roughly as a 'main' method would. A program that only uses
// that one event, however, isn't going to be very reactive. By using
// other events, we can write a fully reactive program.
public class GoodbyeWorld extends BaseHandler {

    // As before we handle the reactor init event.
    @Override
    public void onReactorInit(Event event) {
        System.out.println("Hello, World!");
    }

    // In addition to an initial event, the reactor also produces an
    // event when it is about to exit. This may not behave much
    // differently than just putting the goodbye print statement inside
    // onReactorInit, but as we grow our program, this piece of it
    // will always be what happens last, and will always happen
    // regardless of what other paths the main logic of our program
    // might take.
    @Override
    public void onReactorFinal(Event e) {
        System.out.println("Goodbye, World!");
    }

    public static void main(String[] args) throws IOException {
        Reactor reactor = Proton.reactor(new GoodbyeWorld());
        reactor.run();
    }
}