org.apache.flink.runtime.state

Class HashMapSerializer<K,V>

java.lang.Object

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

org.apache.flink.runtime.state.HashMapSerializer<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

@Internal
public final class HashMapSerializer<K,V>
extends org.apache.flink.api.common.typeutils.TypeSerializer<HashMap<K,V>>

A serializer for HashMap. 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
HashMapSerializer(org.apache.flink.api.common.typeutils.TypeSerializer<K> keySerializer, org.apache.flink.api.common.typeutils.TypeSerializer<V> valueSerializer) Creates a map serializer that uses the given serializers to serialize the key-value pairs in the map.

Method Summary

Modifier and Type	Method and Description
boolean	canEqual(Object obj)
void	copy(org.apache.flink.core.memory.DataInputView source, org.apache.flink.core.memory.DataOutputView target)
HashMap<K,V>	copy(HashMap<K,V> from)
HashMap<K,V>	copy(HashMap<K,V> from, HashMap<K,V> reuse)
HashMap<K,V>	createInstance()
HashMap<K,V>	deserialize(org.apache.flink.core.memory.DataInputView source)
HashMap<K,V>	deserialize(HashMap<K,V> reuse, org.apache.flink.core.memory.DataInputView source)
org.apache.flink.api.common.typeutils.TypeSerializer<HashMap<K,V>>	duplicate()
org.apache.flink.api.common.typeutils.CompatibilityResult<HashMap<K,V>>	ensureCompatibility(org.apache.flink.api.common.typeutils.TypeSerializerConfigSnapshot configSnapshot)
boolean	equals(Object obj)
org.apache.flink.api.common.typeutils.TypeSerializer<K>	getKeySerializer()
int	getLength()
org.apache.flink.api.common.typeutils.TypeSerializer<V>	getValueSerializer()
int	hashCode()
boolean	isImmutableType()
void	serialize(HashMap<K,V> map, org.apache.flink.core.memory.DataOutputView target)
org.apache.flink.api.common.typeutils.TypeSerializerConfigSnapshot	snapshotConfiguration()

Methods inherited from class java.lang.Object

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

Constructor Detail

HashMapSerializer

public HashMapSerializer(org.apache.flink.api.common.typeutils.TypeSerializer<K> keySerializer,
                         org.apache.flink.api.common.typeutils.TypeSerializer<V> valueSerializer)

Creates a map serializer that uses the given serializers to serialize the key-value pairs in the map.

Parameters:

keySerializer - The serializer for the keys in the map

valueSerializer - The serializer for the values in the map

Method Detail

getKeySerializer

public org.apache.flink.api.common.typeutils.TypeSerializer<K> getKeySerializer()

getValueSerializer

public org.apache.flink.api.common.typeutils.TypeSerializer<V> getValueSerializer()

isImmutableType

public boolean isImmutableType()

Specified by:

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

duplicate

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

Specified by:

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

createInstance

public HashMap<K,V> createInstance()

Specified by:

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

copy

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

Specified by:

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

copy

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

Specified by:

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

getLength

public int getLength()

Specified by:

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

serialize

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

Specified by:

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

Throws:

IOException

deserialize

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

Specified by:

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

Throws:

IOException

deserialize

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

Specified by:

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

Throws:

IOException

equals

public boolean equals(Object obj)

Specified by:

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

canEqual

public boolean canEqual(Object obj)

Specified by:

canEqual in class org.apache.flink.api.common.typeutils.TypeSerializer<HashMap<K,V>>

hashCode

public int hashCode()

Specified by:

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

snapshotConfiguration

public org.apache.flink.api.common.typeutils.TypeSerializerConfigSnapshot snapshotConfiguration()

Specified by:

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

ensureCompatibility

public org.apache.flink.api.common.typeutils.CompatibilityResult<HashMap<K,V>> ensureCompatibility(org.apache.flink.api.common.typeutils.TypeSerializerConfigSnapshot configSnapshot)

Specified by:

ensureCompatibility in class org.apache.flink.api.common.typeutils.TypeSerializer<HashMap<K,V>>