content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.alibaba.nacos.example;
  
  import com.alibaba.nacos.api.exception.NacosException;
  import com.alibaba.nacos.api.naming.NamingFactory;
  import com.alibaba.nacos.api.naming.NamingService;
  import com.alibaba.nacos.api.naming.listener.AbstractEventListener;
  import com.alibaba.nacos.api.naming.listener.Event;
  import com.alibaba.nacos.api.naming.listener.NamingEvent;
  
  import java.util.Properties;
  import java.util.concurrent.Executor;
  import java.util.concurrent.LinkedBlockingQueue;
  import java.util.concurrent.ThreadPoolExecutor;
  import java.util.concurrent.TimeUnit;
  
  /**
   * Nacos naming example.
   * <p>Add the JVM parameter to run the NamingExample:</p>
   * {@code -DserverAddr=${nacos.server.ip}:${nacos.server.port} -Dnamespace=${namespaceId}}
   *
   * @author nkorange
   */
  public class NamingExample {
      
      private static final String INSTANCE_SERVICE_NAME = "nacos.test.3";
      
      private static final String INSTANCE_IP = "11.11.11.11";
      
      private static final int INSTANCE_PORT = 8888;
      
      private static final String INSTANCE_CLUSTER_NAME = "TEST1";
      
      public static void main(String[] args) throws NacosException, InterruptedException {
          
          Properties properties = new Properties();
          properties.setProperty("serverAddr", System.getProperty("serverAddr", "localhost"));
          properties.setProperty("namespace", System.getProperty("namespace", "public"));
          
          NamingService naming = NamingFactory.createNamingService(properties);
          
          naming.registerInstance(INSTANCE_SERVICE_NAME, INSTANCE_IP, INSTANCE_PORT, INSTANCE_CLUSTER_NAME);
      
          Executor executor = new ThreadPoolExecutor(1, 1, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>(),
                  runnable -> {
                      Thread thread = new Thread(runnable);
                      thread.setName("test-thread");
                      return thread;
                  });
      
          naming.subscribe(INSTANCE_SERVICE_NAME, new AbstractEventListener() {
          
              //EventListener onEvent is sync to handle, If process too low in onEvent, maybe block other onEvent callback.
              //So you can override getExecutor() to async handle event.
              @Override
              public Executor getExecutor() {
                  return executor;
              }
          
              @Override
              public void onEvent(Event event) {
                  System.out.println("[serviceName] " + ((NamingEvent) event).getServiceName());
                  System.out.println("[instances from event] " + ((NamingEvent) event).getInstances());
              }
          });
          
          Thread.sleep(1000);
      
          System.out.println("[instances after register] " + naming.getAllInstances(INSTANCE_SERVICE_NAME));
          
          Thread.sleep(1000);
      
          naming.deregisterInstance(INSTANCE_SERVICE_NAME, INSTANCE_IP, INSTANCE_PORT, INSTANCE_CLUSTER_NAME);
      
          Thread.sleep(1000);
          
          System.out.println("[instances after deregister] " + naming.getAllInstances(INSTANCE_SERVICE_NAME));
          
          Thread.sleep(1000);
      }
  }
  