pekko/akka-docs/src/test/java/jdocs/cluster/ClusterDocTest.java

/*
 * Copyright (C) 2015-2019 Lightbend Inc. <https://www.lightbend.com>
 */

package jdocs.cluster;

import akka.testkit.javadsl.TestKit;
import com.typesafe.config.ConfigFactory;

import java.util.LinkedList;
import java.util.List;
import java.util.Set;
import jdocs.AbstractJavaTest;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

//#join-seed-nodes-imports
import akka.actor.Address;
import akka.cluster.Cluster;

//#join-seed-nodes-imports
import akka.actor.ActorSystem;
import akka.cluster.Member;


public class ClusterDocTest extends AbstractJavaTest {
  
  static ActorSystem system;
  
  @BeforeClass
  public static void setup() {
    system = ActorSystem.create("ClusterDocTest", 
        ConfigFactory.parseString(scala.docs.cluster.ClusterDocSpec.config()));
  }

  @AfterClass
  public static void tearDown() {
    TestKit.shutdownActorSystem(system);
    system = null;
  }

  @Test
  public void demonstrateLeave() {
    //#leave
    final Cluster cluster = Cluster.get(system);
    cluster.leave(cluster.selfAddress());
    //#leave

  }
  
  // compile only 
  @SuppressWarnings("unused")
  public void demonstrateDataCenter() {
    //#dcAccess
    final Cluster cluster = Cluster.get(system);
    // this node's data center
    String dc = cluster.selfDataCenter();
    // all known data centers
    Set<String> allDc = cluster.state().getAllDataCenters();
    // a specific member's data center
    Member aMember = cluster.state().getMembers().iterator().next();
    String aDc = aMember.dataCenter();
    //#dcAccess
  }

  // compile only
  @SuppressWarnings("unused")
  public void demonstrateJoinSeedNodes() {
    //#join-seed-nodes
    final Cluster cluster = Cluster.get(system);
    List<Address> list = new LinkedList<>(); //replace this with your method to dynamically get seed nodes
    cluster.joinSeedNodes(list);
    //#join-seed-nodes
  }
}