/tags/release-0.1-rc2/hive/external/serde/src/java/org/apache/hadoop/hive/serde2/objectinspector/UnionObjectInspector.java

/**

 * 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.hadoop.hive.serde2.objectinspector;



import java.util.List;



/**

 * UnionObjectInspector works on union data that is stored as UnionObject.

 *

 * It holds the list of the object inspectors corresponding to each type of the

 * object the Union can hold.

 *

 * UnionObjectInspector.

 *

 */

public interface UnionObjectInspector extends ObjectInspector {



  /**

   *  Returns the array of ObjectInspectors that are for each of the tags.

   */

  List<ObjectInspector> getObjectInspectors();



  /**

   *   Return the tag of the object.

   */

  byte getTag(Object o);



  /**

   *  Return the field based on the tag associated with the Object.

   */

  Object getField(Object o);



}