pekko/akka-docs/rst/common/code/docs/circuitbreaker/DangerousJavaActor.java

/**
 * Copyright (C) 2009-2016 Lightbend Inc. <http://www.lightbend.com>
 */
package docs.circuitbreaker;

//#imports1

import akka.actor.UntypedActor;
import scala.concurrent.Future;
import akka.event.LoggingAdapter;
import scala.concurrent.duration.Duration;
import akka.pattern.CircuitBreaker;
import akka.event.Logging;

import static akka.pattern.Patterns.pipe;
import static akka.dispatch.Futures.future;

import java.util.concurrent.Callable;

//#imports1

//#circuit-breaker-initialization
public class DangerousJavaActor extends UntypedActor {

  private final CircuitBreaker breaker;
  private final LoggingAdapter log = Logging.getLogger(getContext().system(), this);

  public DangerousJavaActor() {
    this.breaker = new CircuitBreaker(
      getContext().dispatcher(), getContext().system().scheduler(),
      5, Duration.create(10, "s"), Duration.create(1, "m"))
      .onOpen(new Runnable() {
        public void run() {
          notifyMeOnOpen();
        }
      });
  }

  public void notifyMeOnOpen() {
    log.warning("My CircuitBreaker is now open, and will not close for one minute");
  }
//#circuit-breaker-initialization

  //#circuit-breaker-usage
  public String dangerousCall() {
    return "This really isn't that dangerous of a call after all";
  }

  @Override
  public void onReceive(Object message) {
    if (message instanceof String) {
      String m = (String) message;
      if ("is my middle name".equals(m)) {
        pipe(
          breaker.callWithCircuitBreaker(() -> 
            future(() -> dangerousCall(), getContext().dispatcher())
          ), getContext().dispatcher()
        ).to(getSender());
      }
      if ("block for me".equals(m)) {
        getSender().tell(breaker
          .callWithSyncCircuitBreaker(
            () -> dangerousCall()), getSelf());
      }
    }
  }
//#circuit-breaker-usage

}