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.ambari.server.orm;
  
  import org.apache.ambari.server.events.JpaInitializedEvent;
  import org.apache.ambari.server.events.publishers.AmbariEventPublisher;
  
  import com.google.inject.Inject;
  import com.google.inject.Singleton;
  import com.google.inject.persist.PersistService;
  
  /**
   * This class needs to be instantiated with Guice to initialize Guice-persist
   */
  @Singleton
  public class GuiceJpaInitializer {
  
    private final AmbariEventPublisher publisher;
  
    /**
     * GuiceJpaInitializer constructor.
     * <p>
     * Starts the JPA service and holds on to an {@link AmbariEventPublisher} for future use.
     *
     * @param service   the persist service
     * @param publisher the Ambari event publisher
     */
    @Inject
    public GuiceJpaInitializer(PersistService service, AmbariEventPublisher publisher) {
      this.publisher = publisher;
      service.start();
    }
  
    /**
     * Called to indicate that the JPA service is initialized and ready for use.
     * <p>
     * This means that the schema for the underlying database matches the JPA entity objects expectations
     * and the PersistService has been started.
     * <p>
     * A {@link JpaInitializedEvent} is published so that subscribers can perform database-related tasks
     * when the infrastructure is ready.
     */
    public void setInitialized() {
      publisher.publish(new JpaInitializedEvent());
    }
  
  }
  