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.internal;
  
  import java.sql.ResultSet;
  import java.sql.SQLException;
  import java.util.Map;
  import java.util.Set;
  
  import org.apache.ambari.server.controller.spi.Resource;
  import org.apache.ambari.server.controller.spi.Resource.Type;
  import org.apache.commons.lang.StringUtils;
  
  /**
   * Abstract resource provider implementation that contains helper methods for
   * retrieving data from a result set.
   */
  public abstract class AbstractJDBCResourceProvider<E extends Enum<E>> extends
      AbstractResourceProvider {
    private final Map<String,E> dbFields;
  
    /**
     * Create a new resource provider.
     * 
     * @param propertyIds
     *          the property ids
     * @param keyPropertyIds
     *          the key property ids
     */
    protected AbstractJDBCResourceProvider(Set<String> propertyIds,
        Map<Type,String> keyPropertyIds) {
      super(propertyIds, keyPropertyIds);
      this.dbFields = getDBFieldMap();
    }
  
    /**
     * Gets a map from property ids to db fields.
     * 
     * @return the map from property ids to db fields.
     */
    protected abstract Map<String,E> getDBFieldMap();
  
    /**
     * Retrieves the db field corresponding to a property id from a result set as
     * a string and sets the resulting string as a resource property.
     * 
     * @param resource
     *          resource object to set the property on
     * @param propertyId
     *          the property id to retrieve from the result set
     * @param rs
     *          the result set
     * @param requestedIds
     *          the requested ids
     * @throws SQLException
     *           if property id cannot be retrieved from the result set
     */
    protected void setString(Resource resource, String propertyId, ResultSet rs,
        Set<String> requestedIds) throws SQLException {
      if (requestedIds.contains(propertyId))
        setResourceProperty(resource, propertyId,
            rs.getString(dbFields.get(propertyId).toString()), requestedIds);
    }
  
    /**
     * Retrieves the db field corresponding to a property id from a result set as
     * an int and sets the resulting int as a resource property.
     * 
     * @param resource
     *          resource object to set the property on
     * @param propertyId
     *          the property id to retrieve from the result set
     * @param rs
     *          the result set
     * @param requestedIds
     *          the requested ids
     * @throws SQLException
     *           if property id cannot be retrieved from the result set
     */
    protected void setInt(Resource resource, String propertyId, ResultSet rs,
        Set<String> requestedIds) throws SQLException {
      if (requestedIds.contains(propertyId))
        setResourceProperty(resource, propertyId,
            rs.getInt(dbFields.get(propertyId).toString()), requestedIds);
    }
  
    /**
     * Retrieves the db field corresponding to a property id from a result set as
     * a long and sets the resulting long as a resource property.
     * 
     * @param resource
     *          resource object to set the property on
     * @param propertyId
     *          the property id to retrieve from the result set
     * @param rs
     *          the result set
     * @param requestedIds
     *          the requested ids
     * @throws SQLException
     *           if property id cannot be retrieved from the result set
     */
    protected void setLong(Resource resource, String propertyId, ResultSet rs,
        Set<String> requestedIds) throws SQLException {
      if (requestedIds.contains(propertyId))
        setResourceProperty(resource, propertyId,
            rs.getLong(dbFields.get(propertyId).toString()), requestedIds);
    }
  
    /**
     * Gets a comma-separated list of db fields corresponding to set of requested
     * ids.
     * 
     * @param requestedIds
     *          the requested ids
     * @return a comma-separated list of db fields
     */
    protected String getDBFieldString(Set<String> requestedIds) {
      String[] tmp = new String[requestedIds.size()];
      int i = 0;
      for (String s : requestedIds)
        if (dbFields.containsKey(s))
          tmp[i++] = dbFields.get(s).toString();
      return StringUtils.join(tmp, ",", 0, i);
    }
  
    /**
     * Gets a db field corresponding to a property id.
     * 
     * @param propertyId
     *          the property id
     * @return the db field enum value
     */
    protected E getDBField(String propertyId) {
      return dbFields.get(propertyId);
    }
  }
  