Package org.apache.flink.streaming.util.serialization

Class JSONKeyValueDeserializationSchema

java.lang.Object

org.apache.flink.streaming.util.serialization.JSONKeyValueDeserializationSchema

All Implemented Interfaces:

Serializable, org.apache.flink.api.java.typeutils.ResultTypeQueryable<com.fasterxml.jackson.databind.node.ObjectNode>, KafkaRecordDeserializationSchema<com.fasterxml.jackson.databind.node.ObjectNode>

@PublicEvolving
public class JSONKeyValueDeserializationSchema
extends Object
implements KafkaRecordDeserializationSchema<com.fasterxml.jackson.databind.node.ObjectNode>

DeserializationSchema that deserializes a JSON String into an ObjectNode.

Key fields can be accessed by calling objectNode.get("key").get(<name>).as(<type>)

Value fields can be accessed by calling objectNode.get("value").get(<name>).as(<type>)

Metadata fields can be accessed by calling objectNode.get("metadata").get(<name>).as(<type>) and include the "offset" (long), "topic" (String) and "partition" (int).

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
JSONKeyValueDeserializationSchema(boolean includeMetadata)

Method Summary

Modifier and Type	Method	Description
void	deserialize(org.apache.kafka.clients.consumer.ConsumerRecord<byte[],byte[]> record, org.apache.flink.util.Collector<com.fasterxml.jackson.databind.node.ObjectNode> out)	Deserializes the byte message.
org.apache.flink.api.common.typeinfo.TypeInformation<com.fasterxml.jackson.databind.node.ObjectNode>	getProducedType()
void	open(org.apache.flink.api.common.serialization.DeserializationSchema.InitializationContext context)	Initialization method for the schema.

Methods inherited from class java.lang.Object

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

Constructor Detail

JSONKeyValueDeserializationSchema

public JSONKeyValueDeserializationSchema(boolean includeMetadata)

Method Detail

open

public void open(org.apache.flink.api.common.serialization.DeserializationSchema.InitializationContext context)
          throws Exception

Description copied from interface: KafkaRecordDeserializationSchema

Initialization method for the schema. It is called before the actual working methods KafkaRecordDeserializationSchema.deserialize(org.apache.kafka.clients.consumer.ConsumerRecord<byte[], byte[]>, org.apache.flink.util.Collector<T>) and thus suitable for one time setup work.

The provided DeserializationSchema.InitializationContext can be used to access additional features such as e.g. registering user metrics.

Specified by:

open in interface KafkaRecordDeserializationSchema<com.fasterxml.jackson.databind.node.ObjectNode>

Parameters:

context - Contextual information that can be used during initialization.

Throws:

Exception

deserialize

public void deserialize(org.apache.kafka.clients.consumer.ConsumerRecord<byte[],byte[]> record,
                        org.apache.flink.util.Collector<com.fasterxml.jackson.databind.node.ObjectNode> out)
                 throws IOException

Description copied from interface: KafkaRecordDeserializationSchema

Deserializes the byte message.

Can output multiple records through the Collector. Note that number and size of the produced records should be relatively small. Depending on the source implementation records can be buffered in memory or collecting records might delay emitting checkpoint barrier.

Specified by:

deserialize in interface KafkaRecordDeserializationSchema<com.fasterxml.jackson.databind.node.ObjectNode>

Parameters:

record - The ConsumerRecord to deserialize.

out - The collector to put the resulting messages.

Throws:

IOException

getProducedType

public org.apache.flink.api.common.typeinfo.TypeInformation<com.fasterxml.jackson.databind.node.ObjectNode> getProducedType()

Specified by:

getProducedType in interface org.apache.flink.api.java.typeutils.ResultTypeQueryable<com.fasterxml.jackson.databind.node.ObjectNode>