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.controller.utilities;
  
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  
  import org.apache.ambari.server.controller.utilities.state.DefaultServiceCalculatedState;
  import org.apache.ambari.server.controller.utilities.state.FlumeServiceCalculatedState;
  import org.apache.ambari.server.controller.utilities.state.HBaseServiceCalculatedState;
  import org.apache.ambari.server.controller.utilities.state.HDFSServiceCalculatedState;
  import org.apache.ambari.server.controller.utilities.state.HiveServiceCalculatedState;
  import org.apache.ambari.server.controller.utilities.state.OozieServiceCalculatedState;
  import org.apache.ambari.server.controller.utilities.state.ServiceCalculatedState;
  import org.apache.ambari.server.controller.utilities.state.YARNServiceCalculatedState;
  import org.apache.ambari.server.state.Service;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  
  public class ServiceCalculatedStateFactory {
  
    private final static ServiceCalculatedState DEFAULT_SERVICE_CALCULATED_STATE = new DefaultServiceCalculatedState();
    private final static Logger LOG = LoggerFactory.getLogger(ServiceCalculatedStateFactory.class);
  
    // cache for the service calculated state objects
    private final static Map<Service.Type, ServiceCalculatedState> serviceStateProviders = new ConcurrentHashMap<>();
  
  
    public static ServiceCalculatedState getServiceStateProvider(String service){
      ServiceCalculatedState suggestedServiceProvider;
      Service.Type serviceType = null;
  
      try {
        serviceType = Service.Type.valueOf(service);
      } catch (Exception e){
        LOG.debug("Could not parse service name \"{}\", will use default state provider", service);
      }
  
      if (serviceType == null) {  // service is unknown, return default service state provider
        return DEFAULT_SERVICE_CALCULATED_STATE;
      }
  
      if (serviceStateProviders.containsKey(serviceType)) {   // use cache on hit
        suggestedServiceProvider = serviceStateProviders.get(serviceType);
      } else {
        switch (serviceType) {
          case HDFS:
            suggestedServiceProvider = new HDFSServiceCalculatedState();
            break;
          case FLUME:
            suggestedServiceProvider = new FlumeServiceCalculatedState();
            break;
          case OOZIE:
            suggestedServiceProvider = new OozieServiceCalculatedState();
            break;
          case YARN:
            suggestedServiceProvider = new YARNServiceCalculatedState();
            break;
          case HIVE:
            suggestedServiceProvider = new HiveServiceCalculatedState();
            break;
          case HBASE:
            suggestedServiceProvider = new HBaseServiceCalculatedState();
            break;
          default:
            suggestedServiceProvider = DEFAULT_SERVICE_CALCULATED_STATE;
            break;
        }
        // lazy cache initialization, create just required objects
        serviceStateProviders.put(serviceType, suggestedServiceProvider);
      }
      return suggestedServiceProvider;
    }
  }
  