org.springframework.integration.annotation

Annotation Type Gateway

@Target(value={METHOD,ANNOTATION_TYPE})
 @Retention(value=RUNTIME)
 @Inherited
 @Documented
public @interface Gateway

Indicates that an interface method is capable of mapping its parameters to a message or message payload. These method-level annotations are detected by the GatewayProxyFactoryBean where the annotation attributes can override the default channel settings.

A method annotated with @Gateway may accept a single non-annotated parameter of type Message or of the intended Message payload type. Method parameters may be mapped to individual Message header values by using the @Header parameter annotation. Alternatively, to pass the entire Message headers map, a Map-typed parameter may be annotated with Headers.

Return values from the annotated method may be of any type. If the declared return value is not a Message, the reply Message's payload will be returned and any type conversion as supported by Spring's SimpleTypeConverter will be applied to the return value if necessary.

Note: unlike @Publisher, this annotation is for exposing a Messaging Endpoint based on a Proxy for the marked interface method. The method invocation causes messaging interaction using an AOP Advice. Method parameters become the part of sent message (payload, headers). The method return value is the result (payload) of the messaging flow invoked by the Proxy.

Author:

Mark Fisher, Gary Russell, Artem Bilan

See Also:

MessagingGateway

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
GatewayHeader[]	headers
String	payloadExpression
String	replyChannel
long	replyTimeout
String	requestChannel
long	requestTimeout

Element Detail

requestChannel

public abstract String requestChannel

Default:

""

replyChannel

public abstract String replyChannel

Default:

""

requestTimeout

public abstract long requestTimeout

Default:

-9223372036854775808L

replyTimeout

public abstract long replyTimeout

Default:

-9223372036854775808L

payloadExpression

public abstract String payloadExpression

Default:

""

headers

public abstract GatewayHeader[] headers

Default:

{}