org.apache.flink.table.dataview

Class MapViewSerializer<K,V>

java.lang.Object

org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

org.apache.flink.table.dataview.MapViewSerializer<K,V>

Type Parameters:

K - The type of the keys in the map.

V - The type of the values in the map.

All Implemented Interfaces:

Serializable, org.apache.flink.api.common.typeutils.LegacySerializerSnapshotTransformer<MapView<K,V>>

@Internal
public class MapViewSerializer<K,V>
extends org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>
implements org.apache.flink.api.common.typeutils.LegacySerializerSnapshotTransformer<MapView<K,V>>

A serializer for MapView. The serializer relies on a key serializer and a value serializer for the serialization of the map's key-value pairs.

The serialization format for the map is as follows: four bytes for the length of the map, followed by the serialized representation of each key-value pair. To allow null values, each value is prefixed by a null marker.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
MapViewSerializer(org.apache.flink.api.common.typeutils.TypeSerializer<Map<K,V>> mapSerializer)

Method Summary

Modifier and Type	Method and Description
void	copy(org.apache.flink.core.memory.DataInputView source, org.apache.flink.core.memory.DataOutputView target)
MapView<K,V>	copy(MapView<K,V> from)
MapView<K,V>	copy(MapView<K,V> from, MapView<K,V> reuse)
MapView<K,V>	createInstance()
MapView<K,V>	deserialize(org.apache.flink.core.memory.DataInputView source)
MapView<K,V>	deserialize(MapView<K,V> reuse, org.apache.flink.core.memory.DataInputView source)
org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>	duplicate()
boolean	equals(Object obj)
int	getLength()
org.apache.flink.api.common.typeutils.TypeSerializer<Map<K,V>>	getMapSerializer()
int	hashCode()
boolean	isImmutableType()
void	serialize(MapView<K,V> record, org.apache.flink.core.memory.DataOutputView target)
org.apache.flink.api.common.typeutils.TypeSerializerSnapshot<MapView<K,V>>	snapshotConfiguration()
<U> org.apache.flink.api.common.typeutils.TypeSerializerSnapshot<MapView<K,V>>	transformLegacySerializerSnapshot(org.apache.flink.api.common.typeutils.TypeSerializerSnapshot<U> legacySnapshot) We need to override this as a LegacySerializerSnapshotTransformer because in Flink 1.6.x and below, this serializer was incorrectly returning directly the snapshot of the nested map serializer as its own snapshot.

Methods inherited from class java.lang.Object

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

Constructor Detail

MapViewSerializer

public MapViewSerializer(org.apache.flink.api.common.typeutils.TypeSerializer<Map<K,V>> mapSerializer)

Method Detail

isImmutableType

public boolean isImmutableType()

Specified by:

isImmutableType in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

duplicate

public org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>> duplicate()

Specified by:

duplicate in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

createInstance

public MapView<K,V> createInstance()

Specified by:

createInstance in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

copy

public MapView<K,V> copy(MapView<K,V> from)

Specified by:

copy in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

copy

public MapView<K,V> copy(MapView<K,V> from,
                         MapView<K,V> reuse)

Specified by:

copy in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

getLength

public int getLength()

Specified by:

getLength in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

serialize

public void serialize(MapView<K,V> record,
                      org.apache.flink.core.memory.DataOutputView target)
               throws IOException

Specified by:

serialize in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

Throws:

IOException

deserialize

public MapView<K,V> deserialize(org.apache.flink.core.memory.DataInputView source)
                         throws IOException

Specified by:

deserialize in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

Throws:

IOException

deserialize

public MapView<K,V> deserialize(MapView<K,V> reuse,
                                org.apache.flink.core.memory.DataInputView source)
                         throws IOException

Specified by:

deserialize in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

Throws:

IOException

copy

public void copy(org.apache.flink.core.memory.DataInputView source,
                 org.apache.flink.core.memory.DataOutputView target)
          throws IOException

Specified by:

copy in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

Throws:

IOException

equals

public boolean equals(Object obj)

Specified by:

equals in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

hashCode

public int hashCode()

Specified by:

hashCode in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

snapshotConfiguration

public org.apache.flink.api.common.typeutils.TypeSerializerSnapshot<MapView<K,V>> snapshotConfiguration()

Specified by:

snapshotConfiguration in class org.apache.flink.api.common.typeutils.TypeSerializer<MapView<K,V>>

transformLegacySerializerSnapshot

public <U> org.apache.flink.api.common.typeutils.TypeSerializerSnapshot<MapView<K,V>> transformLegacySerializerSnapshot(org.apache.flink.api.common.typeutils.TypeSerializerSnapshot<U> legacySnapshot)

We need to override this as a LegacySerializerSnapshotTransformer because in Flink 1.6.x and below, this serializer was incorrectly returning directly the snapshot of the nested map serializer as its own snapshot.

This method transforms the incorrect map serializer snapshot to be a proper MapViewSerializerSnapshot.

Specified by:

transformLegacySerializerSnapshot in interface org.apache.flink.api.common.typeutils.LegacySerializerSnapshotTransformer<MapView<K,V>>

getMapSerializer

public org.apache.flink.api.common.typeutils.TypeSerializer<Map<K,V>> getMapSerializer()