org.apache.flink.connector.pulsar.source

Interface MessageDeserializer<T>

All Superinterfaces:

org.apache.flink.api.java.typeutils.ResultTypeQueryable<T>, Serializable

public interface MessageDeserializer<T>
extends Serializable, org.apache.flink.api.java.typeutils.ResultTypeQueryable<T>

An interface for the deserialization of Pulsar messages.

Method Summary

Modifier and Type	Method and Description
void	deserialize(org.apache.pulsar.client.api.Message<?> message, org.apache.flink.util.Collector<T> collector) Deserialize a consumer record into the given collector.
boolean	isEndOfStream(T nextElement) Method to decide whether the element signals the end of the stream.
default void	open(org.apache.flink.api.common.serialization.DeserializationSchema.InitializationContext context) Initialization method for the schema.
static <V> MessageDeserializer<V>	valueOnly(org.apache.flink.api.common.serialization.DeserializationSchema<V> valueDeserializer) Wraps a Flink DeserializationSchema to a MessageDeserializer.

Methods inherited from interface org.apache.flink.api.java.typeutils.ResultTypeQueryable

getProducedType

Method Detail

open

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

Initialization method for the schema. It is called before the actual working methods deserialize(org.apache.pulsar.client.api.Message<?>, 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.

Parameters:

context - Contextual information that can be used during initialization.

Throws:

Exception

deserialize

void deserialize(org.apache.pulsar.client.api.Message<?> message,
                 org.apache.flink.util.Collector<T> collector)
          throws IOException

Deserialize a consumer record into the given collector.

Parameters:

message - the Message to deserialize.

Throws:

IOException - if the deserialization failed.

isEndOfStream

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.

Parameters:

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

Returns:

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

valueOnly

static <V> MessageDeserializer<V> valueOnly(org.apache.flink.api.common.serialization.DeserializationSchema<V> valueDeserializer)

Wraps a Flink DeserializationSchema to a MessageDeserializer.

Type Parameters:

V - the value type.

Parameters:

valueDeserializer - the deserializer class used to deserialize the value.

Returns:

A MessageDeserializer that deserialize the value with the given deserializer.