org.apache.flink.streaming.util.serialization

Class TypeInformationKeyValueSerializationSchema<K,V>

java.lang.Object

org.apache.flink.streaming.util.serialization.TypeInformationKeyValueSerializationSchema<K,V>

Type Parameters:

K - The key type to be serialized.

V - The value type to be serialized.

All Implemented Interfaces:

Serializable, org.apache.flink.api.java.typeutils.ResultTypeQueryable<org.apache.flink.api.java.tuple.Tuple2<K,V>>, KeyedDeserializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>, KeyedSerializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>

public class TypeInformationKeyValueSerializationSchema<K,V>
extends Object
implements KeyedDeserializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>, KeyedSerializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>

A serialization and deserialization schema for Key Value Pairs that uses Flink's serialization stack to transform typed from and to byte arrays.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
TypeInformationKeyValueSerializationSchema(Class<K> keyClass, Class<V> valueClass, org.apache.flink.api.common.ExecutionConfig config) Creates a new de-/serialization schema for the given types.
TypeInformationKeyValueSerializationSchema(org.apache.flink.api.common.typeinfo.TypeInformation<K> keyTypeInfo, org.apache.flink.api.common.typeinfo.TypeInformation<V> valueTypeInfo, org.apache.flink.api.common.ExecutionConfig ec) Creates a new de-/serialization schema for the given types.

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.flink.api.java.tuple.Tuple2<K,V>	deserialize(byte[] messageKey, byte[] message, String topic, int partition, long offset) Deserializes the byte message.
org.apache.flink.api.common.typeinfo.TypeInformation<org.apache.flink.api.java.tuple.Tuple2<K,V>>	getProducedType()
boolean	isEndOfStream(org.apache.flink.api.java.tuple.Tuple2<K,V> nextElement) This schema never considers an element to signal end-of-stream, so this method returns always false.
byte[]	serializeKey(org.apache.flink.api.java.tuple.Tuple2<K,V> element) Serializes the key of the incoming element to a byte array This method might return null if no key is available.
byte[]	serializeValue(org.apache.flink.api.java.tuple.Tuple2<K,V> element) Serializes the value of the incoming element to a byte array

Methods inherited from class java.lang.Object

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

Constructor Detail

TypeInformationKeyValueSerializationSchema

public TypeInformationKeyValueSerializationSchema(org.apache.flink.api.common.typeinfo.TypeInformation<K> keyTypeInfo,
                                          org.apache.flink.api.common.typeinfo.TypeInformation<V> valueTypeInfo,
                                          org.apache.flink.api.common.ExecutionConfig ec)

Creates a new de-/serialization schema for the given types.

Parameters:

keyTypeInfo - The type information for the key type de-/serialized by this schema.

valueTypeInfo - The type information for the value type de-/serialized by this schema.

ec - The execution config, which is used to parametrize the type serializers.

TypeInformationKeyValueSerializationSchema

public TypeInformationKeyValueSerializationSchema(Class<K> keyClass,
                                          Class<V> valueClass,
                                          org.apache.flink.api.common.ExecutionConfig config)

Creates a new de-/serialization schema for the given types. This constructor accepts the types as classes and internally constructs the type information from the classes.

If the types are parametrized and cannot be fully defined via classes, use the constructor that accepts TypeInformation instead.

Parameters:

keyClass - The class of the key de-/serialized by this schema.

valueClass - The class of the value de-/serialized by this schema.

config - The execution config, which is used to parametrize the type serializers.

Method Detail

deserialize

public org.apache.flink.api.java.tuple.Tuple2<K,V> deserialize(byte[] messageKey,
                                                      byte[] message,
                                                      String topic,
                                                      int partition,
                                                      long offset)
                                                        throws IOException

Description copied from interface: KeyedDeserializationSchema

Deserializes the byte message.

Specified by:

deserialize in interface KeyedDeserializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>

Parameters:

messageKey - the key as a byte array (null if no key has been set)

message - The message, as a byte array. (null if the message was empty or deleted)

partition - The partition the message has originated from

offset - the offset of the message in the original source (for example the Kafka offset) @return The deserialized message as an object.

Throws:

IOException

isEndOfStream

public boolean isEndOfStream(org.apache.flink.api.java.tuple.Tuple2<K,V> nextElement)

This schema never considers an element to signal end-of-stream, so this method returns always false.

Specified by:

isEndOfStream in interface KeyedDeserializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>

Parameters:

nextElement - The element to test for the end-of-stream signal.

Returns:

Returns false.

serializeKey

public byte[] serializeKey(org.apache.flink.api.java.tuple.Tuple2<K,V> element)

Description copied from interface: KeyedSerializationSchema

Serializes the key of the incoming element to a byte array This method might return null if no key is available.

Specified by:

serializeKey in interface KeyedSerializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>

Parameters:

element - The incoming element to be serialized

Returns:

the key of the element as a byte array

serializeValue

public byte[] serializeValue(org.apache.flink.api.java.tuple.Tuple2<K,V> element)

Description copied from interface: KeyedSerializationSchema

Serializes the value of the incoming element to a byte array

Specified by:

serializeValue in interface KeyedSerializationSchema<org.apache.flink.api.java.tuple.Tuple2<K,V>>

Parameters:

element - The incoming element to be serialized

Returns:

the value of the element as a byte array

getProducedType

public org.apache.flink.api.common.typeinfo.TypeInformation<org.apache.flink.api.java.tuple.Tuple2<K,V>> getProducedType()

Specified by:

getProducedType in interface org.apache.flink.api.java.typeutils.ResultTypeQueryable<org.apache.flink.api.java.tuple.Tuple2<K,V>>