org.springframework.messaging.handler.annotation.support

Class PayloadArgumentResolver

java.lang.Object

org.springframework.messaging.handler.annotation.support.PayloadArgumentResolver

All Implemented Interfaces:

HandlerMethodArgumentResolver

public class PayloadArgumentResolver
extends java.lang.Object
implements HandlerMethodArgumentResolver

A resolver to extract and convert the payload of a message using a MessageConverter. It also validates the payload using a Validator if the argument is annotated with a Validation annotation.

This HandlerMethodArgumentResolver should be ordered last as it supports all types and does not require the Payload annotation.

Since:

4.0

Author:

Rossen Stoyanchev, Brian Clozel, Stephane Nicoll

Constructor Summary

Constructors

Constructor and Description
PayloadArgumentResolver(MessageConverter messageConverter, org.springframework.validation.Validator validator)

Method Summary

Modifier and Type	Method and Description
protected boolean	isEmptyPayload(java.lang.Object payload) Specify if the given payload is empty.
java.lang.Object	resolveArgument(org.springframework.core.MethodParameter param, Message<?> message) Resolves a method parameter into an argument value from a given message.
boolean	supportsParameter(org.springframework.core.MethodParameter parameter) Whether the given method parameter is supported by this resolver.
protected void	validate(Message<?> message, org.springframework.core.MethodParameter parameter, java.lang.Object target)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PayloadArgumentResolver

public PayloadArgumentResolver(MessageConverter messageConverter,
                               org.springframework.validation.Validator validator)

Method Detail

supportsParameter

public boolean supportsParameter(org.springframework.core.MethodParameter parameter)

Description copied from interface: HandlerMethodArgumentResolver

Whether the given method parameter is supported by this resolver.

Specified by:

supportsParameter in interface HandlerMethodArgumentResolver

Parameters:

parameter - the method parameter to check

Returns:

true if this resolver supports the supplied parameter; false otherwise

resolveArgument

public java.lang.Object resolveArgument(org.springframework.core.MethodParameter param,
                                        Message<?> message)
                                 throws java.lang.Exception

Description copied from interface: HandlerMethodArgumentResolver

Resolves a method parameter into an argument value from a given message.

Specified by:

resolveArgument in interface HandlerMethodArgumentResolver

Parameters:

param - the method parameter to resolve. This parameter must have previously been passed to HandlerMethodArgumentResolver.supportsParameter(org.springframework.core.MethodParameter) and it must have returned true

message - the currently processed message

Returns:

the resolved argument value, or null.

Throws:

java.lang.Exception - in case of errors with the preparation of argument values

isEmptyPayload

protected boolean isEmptyPayload(java.lang.Object payload)

Specify if the given payload is empty.

Parameters:

payload - the payload to check (can be null)

validate

protected void validate(Message<?> message,
                        org.springframework.core.MethodParameter parameter,
                        java.lang.Object target)