org.apache.pulsar.client.api

Interface MessagePayloadContext

public interface MessagePayloadContext

The context of the message payload, which usually represents a batched message (batch) or a single message.

Method Summary

Modifier and Type	Method and Description
<T> Message<T>	asSingleMessage(MessagePayload payload, Schema<T> schema) Convert the given payload to a single message if the entry is not a batch.
<T> Message<T>	getMessageAt(int index, int numMessages, MessagePayload payload, boolean containMetadata, Schema<T> schema) Get the internal single message with a specific index from a payload if the payload is a batch.
int	getNumMessages() Get the number of messages when the payload is produced by Pulsar producer.
String	getProperty(String key) Get a value associated with the given key.
boolean	isBatch() Check whether the payload is a batch when the payload is produced by Pulsar producer.

Method Detail

getProperty

String getProperty(String key)

Get a value associated with the given key. When the message payload is not produced by Pulsar producer, a specific property is usually added to indicate the format. So this method is useful to determine whether the payload is produced by Pulsar producer.

Parameters:

key -

Returns:

the value associated with the key or null if the key or value doesn't exist

getNumMessages

int getNumMessages()

Get the number of messages when the payload is produced by Pulsar producer.

Returns:

the number of messages

isBatch

boolean isBatch()

Check whether the payload is a batch when the payload is produced by Pulsar producer.

Returns:

true if the payload is a batch

getMessageAt

<T> Message<T> getMessageAt(int index,
                            int numMessages,
                            MessagePayload payload,
                            boolean containMetadata,
                            Schema<T> schema)

Get the internal single message with a specific index from a payload if the payload is a batch.

Type Parameters:

T -

Parameters:

index - the batch index

numMessages - the number of messages in the batch

payload - the message payload

containMetadata - whether the payload contains the single message metadata

schema - the schema of the batch

Returns:

the created message

asSingleMessage

<T> Message<T> asSingleMessage(MessagePayload payload,
                               Schema<T> schema)

Convert the given payload to a single message if the entry is not a batch.

Type Parameters:

T -

Parameters:

payload - the message payload

schema - the schema of the message

Returns:

the created message