org.apache.hadoop.hive.serde2

Class AbstractSerDe

java.lang.Object

org.apache.hadoop.hive.serde2.AbstractSerDe

All Implemented Interfaces:

Deserializer, SerDe, Serializer

Direct Known Subclasses:

AbstractEncodingAwareSerDe, AvroSerDe, BinarySortableSerDe, ColumnarSerDeBase, DynamicSerDe, HBaseSerDe, LazyBinarySerDe, MetadataTypedColumnsetSerDe, MultiDelimitSerDe, NullStructSerDe, OpenCSVSerde, ParquetHiveSerDe, RegexSerDe, RegexSerDe, TypedBytesSerDe, TypedSerDe

public abstract class AbstractSerDe
extends Object
implements SerDe

Abstract class for implementing SerDe. The abstract class has been created, so that new methods can be added in the underlying interface, SerDe, and only implementations that need those methods overwrite it.

Field Summary

Fields

Modifier and Type	Field and Description
protected String	configErrors

Constructor Summary

Constructors

Constructor and Description
AbstractSerDe()

Method Summary

Methods

Modifier and Type	Method and Description
abstract Object	deserialize(org.apache.hadoop.io.Writable blob) Deserialize an object out of a Writable blob.
String	getConfigurationErrors() Get the error messages during the Serde configuration
abstract ObjectInspector	getObjectInspector() Get the object inspector that can be used to navigate through the internal structure of the Object returned from deserialize(...).
abstract SerDeStats	getSerDeStats() Returns statistics collected when serializing
abstract Class<? extends org.apache.hadoop.io.Writable>	getSerializedClass() Returns the Writable class that would be returned by the serialize method.
abstract void	initialize(org.apache.hadoop.conf.Configuration conf, Properties tbl) Deprecated.
void	initialize(org.apache.hadoop.conf.Configuration configuration, Properties tableProperties, Properties partitionProperties) Initialize the SerDe.
abstract org.apache.hadoop.io.Writable	serialize(Object obj, ObjectInspector objInspector) Serialize an object by navigating inside the Object with the ObjectInspector.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

configErrors

protected String configErrors

Constructor Detail

AbstractSerDe

public AbstractSerDe()

Method Detail

initialize

public void initialize(org.apache.hadoop.conf.Configuration configuration,
              Properties tableProperties,
              Properties partitionProperties)
                throws SerDeException

Initialize the SerDe. By default, this will use one set of properties, either the table properties or the partition properties. If a SerDe needs access to both sets, it should override this method. Eventually, once all SerDes have implemented this method, we should convert it to an abstract method.

Parameters:

configuration - Hadoop configuration

tableProperties - Table properties

partitionProperties - Partition properties

Throws:

SerDeException

initialize

@Deprecated
public abstract void initialize(@Nullable
                         org.apache.hadoop.conf.Configuration conf,
                         Properties tbl)
                         throws SerDeException

Deprecated.

Initialize the HiveSerializer.

Specified by:

initialize in interface Deserializer

Specified by:

initialize in interface Serializer

Parameters:

conf - System properties. Can be null in compile time

tbl - table properties

Throws:

SerDeException

getSerializedClass

public abstract Class<? extends org.apache.hadoop.io.Writable> getSerializedClass()

Returns the Writable class that would be returned by the serialize method. This is used to initialize SequenceFile header.

Specified by:

getSerializedClass in interface Serializer

serialize

public abstract org.apache.hadoop.io.Writable serialize(Object obj,
                                      ObjectInspector objInspector)
                                                 throws SerDeException

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.

Specified by:

serialize in interface Serializer

Throws:

SerDeException

getSerDeStats

public abstract SerDeStats getSerDeStats()

Returns statistics collected when serializing

Specified by:

getSerDeStats in interface Deserializer

Specified by:

getSerDeStats in interface Serializer

deserialize

public abstract Object deserialize(org.apache.hadoop.io.Writable blob)
                            throws SerDeException

Deserialize an object out of a Writable blob. In most cases, the return value of this function will be constant since the function will reuse the returned object. If the client wants to keep a copy of the object, the client needs to clone the returned value by calling ObjectInspectorUtils.getStandardObject().

Specified by:

deserialize in interface Deserializer

Parameters:

blob - The Writable object containing a serialized object

Returns:

A Java object representing the contents in the blob.

Throws:

SerDeException

getObjectInspector

public abstract ObjectInspector getObjectInspector()
                                            throws SerDeException

Get the object inspector that can be used to navigate through the internal structure of the Object returned from deserialize(...).

Specified by:

getObjectInspector in interface Deserializer

Throws:

SerDeException

getConfigurationErrors

public String getConfigurationErrors()

Get the error messages during the Serde configuration

Returns:

The error messages in the configuration which are empty if no error occurred