90 lines
2.4 KiB
Java
90 lines
2.4 KiB
Java
/*
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* Copyright (C) 2009-2022 Lightbend Inc. <https://www.lightbend.com>
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*/
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package jdocs.extension;
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// #imports
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import org.apache.pekko.actor.*;
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import java.util.concurrent.atomic.AtomicLong;
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// #imports
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import jdocs.AbstractJavaTest;
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import org.junit.Test;
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public class ExtensionDocTest extends AbstractJavaTest {
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public
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// #extension
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static class CountExtensionImpl implements Extension {
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// Since this Extension is a shared instance
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// per ActorSystem we need to be threadsafe
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private final AtomicLong counter = new AtomicLong(0);
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// This is the operation this Extension provides
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public long increment() {
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return counter.incrementAndGet();
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}
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}
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// #extension
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public
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// #extensionid
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static class CountExtension extends AbstractExtensionId<CountExtensionImpl>
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implements ExtensionIdProvider {
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// This will be the identifier of our CountExtension
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public static final CountExtension CountExtensionProvider = new CountExtension();
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private CountExtension() {}
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// The lookup method is required by ExtensionIdProvider,
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// so we return ourselves here, this allows us
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// to configure our extension to be loaded when
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// the ActorSystem starts up
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public CountExtension lookup() {
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return CountExtension.CountExtensionProvider; // The public static final
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}
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// This method will be called by Akka
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// to instantiate our Extension
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public CountExtensionImpl createExtension(ExtendedActorSystem system) {
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return new CountExtensionImpl();
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}
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}
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// #extensionid
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public
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// #extension-usage-actor
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static class MyActor extends AbstractActor {
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@Override
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public Receive createReceive() {
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return receiveBuilder()
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.matchAny(
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msg -> {
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// typically you would use static import of the
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// CountExtension.CountExtensionProvider field
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CountExtension.CountExtensionProvider.get(getContext().getSystem()).increment();
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})
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.build();
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}
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}
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// #extension-usage-actor
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@Test
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public void demonstrateHowToCreateAndUseAnAkkaExtensionInJava() {
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final ActorSystem system = null;
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try {
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// #extension-usage
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// typically you would use static import of the
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// CountExtension.CountExtensionProvider field
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CountExtension.CountExtensionProvider.get(system).increment();
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// #extension-usage
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} catch (Exception e) {
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// do nothing
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}
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}
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}
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