Package cz.o2.proxima.direct.io.kafka

Interface ElementSerializer<K,V>

Type Parameters:

K - type of key read from Kafka

V - type of value read from Kafka

All Superinterfaces:

java.io.Serializable

All Known Implementing Classes:

KafkaStreamElement.KafkaStreamElementSerializer, ValueAsBytesSerializer, ValueAsStringSerializer

public interface ElementSerializer<K,V>
extends java.io.Serializable

A parser that transforms KV from Kafka (byte[], byte[]) into StreamElement.

Method Summary

Modifier and Type	Method	Description
org.apache.kafka.common.serialization.Serde<K>	keySerde()	Retrieve Serde for type K.
StreamElement	read(org.apache.kafka.clients.consumer.ConsumerRecord<K,V> record, EntityDescriptor entityDesc)	Parse the raw bytes from Kafka and return a StreamElement.
default void	setup(EntityDescriptor entityDescriptor)	Life-cycle method called after being instantiated to be able to parameterize itself from the given EntityDescriptor.
default boolean	storesSequentialId()
org.apache.kafka.common.serialization.Serde<V>	valueSerde()	Retrieve Serde for type V.
org.apache.kafka.clients.producer.ProducerRecord<K,V>	write(java.lang.String topic, int partition, StreamElement element)	Convert StreamElement into ProducerRecord.

Method Detail

setup

default void setup(EntityDescriptor entityDescriptor)

Life-cycle method called after being instantiated to be able to parameterize itself from the given EntityDescriptor.

Parameters:

entityDescriptor - the entity that this serializer will be used for

read

@Nullable
StreamElement read(org.apache.kafka.clients.consumer.ConsumerRecord<K,V> record,
                   EntityDescriptor entityDesc)

Parse the raw bytes from Kafka and return a StreamElement.

Parameters:

record - a ConsumerRecord to be parsed

entityDesc - descriptor of entity being read

Returns:

the StreamElement or null on parse error

write

org.apache.kafka.clients.producer.ProducerRecord<K,V> write(java.lang.String topic,
                                                                  int partition,
                                                                  StreamElement element)

Convert StreamElement into ProducerRecord.

Parameters:

topic - the target topic

partition - the target partition

element - the StreamElement to convert

Returns:

the ProducerRecord to write to Kafka

keySerde

org.apache.kafka.common.serialization.Serde<K> keySerde()

Retrieve Serde for type K.

Returns:

Serde for key

valueSerde

org.apache.kafka.common.serialization.Serde<V> valueSerde()

Retrieve Serde for type V.

Returns:

Serde for value

storesSequentialId

default boolean storesSequentialId()

Returns:

true if this serializer reads and writes sequential IDs of StreamElement (if any).