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/*
 * 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;

import java.util.Properties;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.io.Writable;

/**
 * Abstract class for implementing Serializer. The abstract class has been created, so that
 * new methods can be added in the underlying interface, Serializer, and only implementations
 * that need those methods overwrite it.
 */
public abstract class AbstractSerializer implements Serializer {

  /**
   * Initialize the HiveSerializer.
   *
   * @param conf
   *          System properties
   * @param tbl
   *          table properties
   * @throws SerDeException
   */
  public abstract void initialize(Configuration conf, Properties tbl) throws SerDeException;

  /**
   * Returns the Writable class that would be returned by the serialize method.
   * This is used to initialize SequenceFile header.
   */
  public abstract Class getSerializedClass();

  /**
   * Serialize an object by navigating inside the Object with the
   * ObjectInspector. In most cases, the return value of this function will be
   * constant since the function will reuse the Writable object. If the client
   * wants to keep a copy of the Writable, the client needs to clone the
   * returned value.
   */
  public abstract Writable serialize(Object obj, ObjectInspector objInspector)
      throws SerDeException;

  /**
   * Returns statistics collected when serializing
   */
  public abstract SerDeStats getSerDeStats();
}