org.apache.flink.api.common.serialization

Class AbstractDeserializationSchema<T>

java.lang.Object

org.apache.flink.api.common.serialization.AbstractDeserializationSchema<T>

Type Parameters:

T - The type created by the deserialization schema.

All Implemented Interfaces:

Serializable, DeserializationSchema<T>, ResultTypeQueryable<T>

@PublicEvolving
public abstract class AbstractDeserializationSchema<T>
extends Object
implements DeserializationSchema<T>

The deserialization schema describes how to turn the byte messages delivered by certain data sources (for example Apache Kafka) into data types (Java/Scala objects) that are processed by Flink.

This base variant of the deserialization schema produces the type information automatically by extracting it from the generic class arguments.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AbstractDeserializationSchema()

Method Summary

Modifier and Type	Method and Description
abstract T	deserialize(byte[] message) De-serializes the byte message.
TypeInformation<T>	getProducedType() Gets the data type (as a TypeInformation) produced by this function or input format.
boolean	isEndOfStream(T 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

AbstractDeserializationSchema

public AbstractDeserializationSchema()

Method Detail

deserialize

public abstract T deserialize(byte[] message)
                       throws IOException

De-serializes the byte message.

Specified by:

deserialize in interface DeserializationSchema<T>

Parameters:

message - The message, as a byte array.

Returns:

The de-serialized message as an object.

Throws:

IOException

isEndOfStream

public boolean isEndOfStream(T nextElement)

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

This default implementation returns always false, meaning the stream is interpreted to be unbounded.

Specified by:

isEndOfStream in interface DeserializationSchema<T>

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<T> 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<T>

Returns:

The data type produced by this function or input format.