org.apache.flink.streaming.util.serialization

Class JSONKeyValueDeserializationSchema

java.lang.Object

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

All Implemented Interfaces:

Serializable, ResultTypeQueryable<org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode>, KeyedDeserializationSchema<org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode>

@PublicEvolving
public class JSONKeyValueDeserializationSchema
extends Object
implements KeyedDeserializationSchema<org.apache.flink.shaded.jackson2.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 and Description
JSONKeyValueDeserializationSchema(boolean includeMetadata)

Method Summary

Modifier and Type	Method and Description
org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode	deserialize(byte[] messageKey, byte[] message, String topic, int partition, long offset) Deserializes the byte message.
TypeInformation<org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode>	getProducedType() Gets the data type (as a TypeInformation) produced by this function or input format.
boolean	isEndOfStream(org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode nextElement) Method to decide whether the element signals the end of the stream.

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

deserialize

public org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode 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.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode>

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).

Returns:

The deserialized message as an object (null if the message cannot be deserialized).

Throws:

IOException

isEndOfStream

public boolean isEndOfStream(org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode nextElement)

Description copied from interface: KeyedDeserializationSchema

Method to decide whether the element signals the end of the stream. If true is returned the element won't be emitted.

Specified by:

isEndOfStream in interface KeyedDeserializationSchema<org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode>

Parameters:

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

Returns:

True, if the element signals end of stream, false otherwise.

getProducedType

public TypeInformation<org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode> getProducedType()

Description copied from interface: ResultTypeQueryable

Gets the data type (as a TypeInformation) produced by this function or input format.

Specified by:

getProducedType in interface ResultTypeQueryable<org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode>

Returns:

The data type produced by this function or input format.