org.apache.hadoop.hive.serde2.Serializer Maven / Gradle / Ivy
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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;
/**
* HiveSerializer is used to serialize data to a Hadoop Writable object. The
* serialize In addition to the interface below, all implementations are assume
* to have a ctor that takes a single 'Table' object as argument.
* All serializers should extend the abstract class AbstractSerializer.
* The interface is necessary for SerDes to be able to implement both Serializer and Deserializer.
*/
public interface Serializer {
/**
* Initialize the HiveSerializer.
*
* @param conf
* System properties
* @param tbl
* table properties
* @throws SerDeException
*/
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.
*/
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.
*/
Writable serialize(Object obj, ObjectInspector objInspector) throws SerDeException;
/**
* Returns statistics collected when serializing
*/
SerDeStats getSerDeStats();
}