Package org.springframework.messaging.converter

Interface SmartMessageConverter

All Superinterfaces:

MessageConverter

All Known Implementing Classes:

AbstractJsonMessageConverter, AbstractMessageConverter, ByteArrayMessageConverter, CompositeMessageConverter, GsonMessageConverter, JsonbMessageConverter, KotlinSerializationJsonMessageConverter, MappingJackson2MessageConverter, MarshallingMessageConverter, ProtobufJsonFormatMessageConverter, ProtobufMessageConverter, StringMessageConverter

public interface SmartMessageConverter
extends MessageConverter

An extended MessageConverter SPI with conversion hint support.

In case of a conversion hint being provided, the framework will call these extended methods if a converter implements this interface, instead of calling the regular fromMessage / toMessage variants.

Since:

4.2.1

Author:

Juergen Hoeller

Method Summary

Modifier and Type	Method	Description
@Nullable Object	fromMessage(Message<?> message, Class<?> targetClass, @Nullable Object conversionHint)	A variant of MessageConverter.fromMessage(Message, Class) which takes an extra conversion context as an argument, allowing to take, for example, annotations on a payload parameter into account.
@Nullable Message<?>	toMessage(Object payload, @Nullable MessageHeaders headers, @Nullable Object conversionHint)	A variant of MessageConverter.toMessage(Object, MessageHeaders) which takes an extra conversion context as an argument, allowing to take, for example, annotations on a return type into account.

Methods inherited from interface org.springframework.messaging.converter.MessageConverter

fromMessage, toMessage

Method Details

fromMessage

@Nullable Object fromMessage(Message<?> message,
 Class<?> targetClass,
 @Nullable Object conversionHint)

A variant of MessageConverter.fromMessage(Message, Class) which takes an extra conversion context as an argument, allowing to take, for example, annotations on a payload parameter into account.

Parameters:

message - the input message

targetClass - the target class for the conversion

conversionHint - an extra object passed to the MessageConverter, for example, the associated MethodParameter (may be null}

Returns:

the result of the conversion, or null if the converter cannot perform the conversion

See Also:

• MessageConverter.fromMessage(Message, Class)

toMessage

@Nullable Message<?> toMessage(Object payload,
 @Nullable MessageHeaders headers,
 @Nullable Object conversionHint)

A variant of MessageConverter.toMessage(Object, MessageHeaders) which takes an extra conversion context as an argument, allowing to take, for example, annotations on a return type into account.

Parameters:

payload - the Object to convert

headers - optional headers for the message (may be null)

conversionHint - an extra object passed to the MessageConverter, for example, the associated MethodParameter (may be null}

Returns:

the new message, or null if the converter does not support the Object type or the target media type

See Also:

• MessageConverter.toMessage(Object, MessageHeaders)