content: /**
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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 org.apache.activemq.maven;
  
  import org.apache.activemq.broker.BrokerFactory;
  import org.apache.activemq.broker.BrokerService;
  import org.apache.maven.plugin.MojoExecutionException;
  
  /**
   * Singleton facade between Maven and one ActiveMQ broker.
   */
  public class Broker {
  
      private static BrokerService broker;
  
      private static boolean[] shutdown;
  
      private static Thread shutdownThread;
  
      public static void start(boolean fork, String configUri) throws MojoExecutionException {
  
          if (broker != null) {
              throw new MojoExecutionException("A local broker is already running");
          }
  
          try {
              broker = BrokerFactory.createBroker(configUri);
              if (fork) {
                  new Thread(new Runnable() {
                      @Override
                      public void run() {
                          try {
                              broker.start();
                              waitForShutdown();
                          } catch (Exception e) {
                              e.printStackTrace();
                          }
                      }
                  }).start();
              } else {
                  broker.start();
                  waitForShutdown();
              }
          } catch (Exception e) {
              throw new MojoExecutionException("Failed to start the ActiveMQ Broker", e);
          }
      }
  
      public static void stop() throws MojoExecutionException {
  
          if (broker == null) {
              throw new MojoExecutionException("The local broker is not running");
          }
  
          try {
              broker.stop();
              broker.waitUntilStopped();
              broker = null;
  
              Runtime.getRuntime().removeShutdownHook(shutdownThread);
  
              // Terminate the shutdown hook thread
              synchronized (shutdown) {
                  shutdown[0] = true;
                  shutdown.notify();
              }
          } catch (Exception e) {
              throw new MojoExecutionException("Failed to stop the ActiveMQ Broker", e);
          }
      }
  
      /**
       * Wait for a shutdown invocation elsewhere
       *
       * @throws Exception
       */
      protected static void waitForShutdown() throws Exception {
          shutdown = new boolean[] { false };
  
          shutdownThread = new Thread() {
              @Override
              public void run() {
                  synchronized (shutdown) {
                      shutdown[0] = true;
                      shutdown.notify();
                  }
              }
          };
  
          Runtime.getRuntime().addShutdownHook(shutdownThread);
  
          // Wait for any shutdown event
          synchronized (shutdown) {
              while (!shutdown[0]) {
                  try {
                      shutdown.wait();
                  } catch (InterruptedException e) {
                  }
              }
          }
  
          // Stop broker
          if (broker != null) {
              broker.stop();
          }
      }
  
      /**
       * Return the broker service created.
       */
      public static BrokerService getBroker() {
          return broker;
      }
  
      /**
       * Override the default creation of the broker service.  Primarily added for testing purposes.
       *
       * @param broker
       */
      public static void setBroker(BrokerService broker) {
          Broker.broker = broker;
      }
  }
  