io.cloudevents.core.message

Interface MessageReader

All Superinterfaces:

CloudEventReader, StructuredMessageReader

All Known Implementing Classes:

BaseBinaryMessageReader, BaseGenericBinaryMessageReaderImpl, BaseStructuredMessageReader, GenericStructuredMessageReader

@ParametersAreNonnullByDefault
public interface MessageReader
extends StructuredMessageReader, CloudEventReader

Represents a CloudEvent message reader.

This class expands the CloudEventReader to define reading both binary and structured messages.

Method Summary

Modifier and Type	Method and Description
Encoding	getEncoding()
default <W extends CloudEventWriter<R>,R> R	read(CloudEventWriterFactory<W,R> writerFactory) Like read(CloudEventWriterFactory, CloudEventDataMapper), but with the identity CloudEventDataMapper.
<W extends CloudEventWriter<R>,R> R	read(CloudEventWriterFactory<W,R> writerFactory, CloudEventDataMapper<? extends CloudEventData> mapper) Read the message as binary encoded message using the provided writer factory.
default <BW extends CloudEventWriter<R>,R> R	read(MessageWriter<BW,R> writer) Read the content of this object using a MessageWriter.
<R> R	read(StructuredMessageWriter<R> writer) Read the message as structured encoded message using the provided writer
default CloudEvent	toEvent() Like toEvent(CloudEventDataMapper), but with the identity CloudEventDataMapper.
default CloudEvent	toEvent(CloudEventDataMapper<? extends CloudEventData> mapper) Translate this message into a CloudEvent representation, mapping the data with the provided mapper.

Methods inherited from interface io.cloudevents.core.message.StructuredMessageReader

from, from

Method Detail

read

default <W extends CloudEventWriter<R>,R> R read(CloudEventWriterFactory<W,R> writerFactory)
                                          throws CloudEventRWException,
                                                 IllegalStateException

Like read(CloudEventWriterFactory, CloudEventDataMapper), but with the identity CloudEventDataMapper.

Specified by:

read in interface CloudEventReader

Throws:

CloudEventRWException

IllegalStateException

See Also:

read(CloudEventWriterFactory, CloudEventDataMapper)

read

<W extends CloudEventWriter<R>,R> R read(CloudEventWriterFactory<W,R> writerFactory,
                                         CloudEventDataMapper<? extends CloudEventData> mapper)
                                  throws CloudEventRWException,
                                         IllegalStateException

Read the message as binary encoded message using the provided writer factory.

Specified by:

read in interface CloudEventReader

Type Parameters:

W - the CloudEventWriter type

R - the return type of the CloudEventWriter

Parameters:

writerFactory - a factory that generates a reader starting from the SpecVersion of the event

mapper - the mapper to use to map the data, if any.

Throws:

CloudEventRWException - if something went wrong during the visit.

IllegalStateException - if the message is not in binary encoding.

read

<R> R read(StructuredMessageWriter<R> writer)
    throws CloudEventRWException,
           IllegalStateException

Read the message as structured encoded message using the provided writer

Specified by:

read in interface StructuredMessageReader

Type Parameters:

R - the return type of the StructuredMessageWriter

Parameters:

writer - Structured Message writer

Returns:

the return value returned by StructuredMessageWriter.setEvent(EventFormat, byte[])

Throws:

CloudEventRWException - if something went wrong during the visit.

IllegalStateException - if the message is not in structured encoding.

getEncoding

Encoding getEncoding()

Returns:

The message encoding

read

default <BW extends CloudEventWriter<R>,R> R read(MessageWriter<BW,R> writer)
                                           throws CloudEventRWException,
                                                  IllegalStateException

Read the content of this object using a MessageWriter. This method allows to transcode an event from one transport to another without converting it to CloudEvent. The resulting encoding will be the same as the original encoding.

Type Parameters:

BW - the CloudEventWriter type

R - the return type of both CloudEventWriter and StructuredMessageWriter

Parameters:

writer - the MessageWriter accepting this Message

Returns:

The return value of the MessageWriter

Throws:

CloudEventRWException - if something went wrong during the visit.

IllegalStateException - if the message has an unknown encoding.

toEvent

default CloudEvent toEvent()
                    throws CloudEventRWException,
                           IllegalStateException

Like toEvent(CloudEventDataMapper), but with the identity CloudEventDataMapper.

Specified by:

toEvent in interface StructuredMessageReader

Throws:

CloudEventRWException

IllegalStateException

See Also:

toEvent(CloudEventDataMapper)

toEvent

default CloudEvent toEvent(CloudEventDataMapper<? extends CloudEventData> mapper)
                    throws CloudEventRWException,
                           IllegalStateException

Translate this message into a CloudEvent representation, mapping the data with the provided mapper.

Specified by:

toEvent in interface StructuredMessageReader

Parameters:

mapper - the mapper to use to map the data, if any.

Returns:

A CloudEvent with the contents of this message.

Throws:

CloudEventRWException - if something went wrong during the read.

IllegalStateException - if the message has an unknown encoding.