+act #20936 add CompletionStage API to CircuitBreaker (#20937)

akka-actor-tests/src/test/java/akka/pattern/CircuitBreakerTest.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2009-2016 Lightbend Inc. <http://www.lightbend.com>
+ */
+package akka.pattern;
+
+import akka.actor.*;
+import akka.testkit.AkkaJUnitActorSystemResource;
+import akka.testkit.AkkaSpec;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.scalatest.junit.JUnitSuite;
+import scala.compat.java8.FutureConverters;
+import scala.concurrent.Await;
+import scala.concurrent.duration.FiniteDuration;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.TimeUnit;
+
+import static org.junit.Assert.assertEquals;
+
+public class CircuitBreakerTest extends JUnitSuite {
+
+  @ClassRule
+  public static AkkaJUnitActorSystemResource actorSystemResource = 
+    new AkkaJUnitActorSystemResource("JavaAPI", AkkaSpec.testConf());
+
+  private final ActorSystem system = actorSystemResource.getSystem();
+
+  @Test
+  public void useCircuitBreakerWithCompletableFuture() throws Exception {
+    final FiniteDuration fiveSeconds = FiniteDuration.create(5, TimeUnit.SECONDS);
+    final FiniteDuration fiveHundredMillis = FiniteDuration.create(500, TimeUnit.MILLISECONDS);
+    final CircuitBreaker breaker = new CircuitBreaker(system.dispatcher(), system.scheduler(), 1, fiveSeconds, fiveHundredMillis);
+
+    final CompletableFuture<String> f = new CompletableFuture<>();
+    f.complete("hello");
+    final CompletionStage<String> res = breaker.callWithCircuitBreakerCS(() -> f);
+    assertEquals("hello", Await.result(FutureConverters.toScala(res), fiveSeconds));
+  }
+
+}