java.lang.Object
- org.springframework.messaging.handler.annotation.support.PayloadMethodArgumentResolver

All Implemented Interfaces:
HandlerMethodArgumentResolver
Direct Known Subclasses:
PayloadArgumentResolver
```
public class PayloadMethodArgumentResolver
extends 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:
5.2
Author:
Rossen Stoyanchev, Juergen Hoeller, Brian Clozel, Stephane Nicoll

Constructor Summary

Constructors
Constructor	Description
`PayloadMethodArgumentResolver(MessageConverter messageConverter)`	Create a new `PayloadArgumentResolver` with the given `MessageConverter`.
`PayloadMethodArgumentResolver(MessageConverter messageConverter, Validator validator)`	Create a new `PayloadArgumentResolver` with the given `MessageConverter` and `Validator`.
`PayloadMethodArgumentResolver(MessageConverter messageConverter, Validator validator, boolean useDefaultResolution)`	Create a new `PayloadArgumentResolver` with the given `MessageConverter` and `Validator`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected boolean`	`isEmptyPayload(Object payload)`	Specify if the given `payload` is empty.
`Object`	`resolveArgument(MethodParameter parameter, Message<?> message)`	Resolves a method parameter into an argument value from a given message.
`protected Class<?>`	`resolveTargetClass(MethodParameter parameter, Message<?> message)`	Resolve the target class to convert the payload to.
`boolean`	`supportsParameter(MethodParameter parameter)`	Whether the given method parameter is supported by this resolver.
`protected void`	`validate(Message<?> message, MethodParameter parameter, Object target)`	Validate the payload if applicable.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - PayloadMethodArgumentResolver
```
public PayloadMethodArgumentResolver(MessageConverter messageConverter)
```
    Create a new PayloadArgumentResolver with the given MessageConverter.
    Parameters:
    messageConverter - the MessageConverter to use (required)
  - PayloadMethodArgumentResolver
```
public PayloadMethodArgumentResolver(MessageConverter messageConverter,
                                     @Nullable
                                     Validator validator)
```
    Create a new PayloadArgumentResolver with the given MessageConverter and Validator.
    Parameters:
    messageConverter - the MessageConverter to use (required)
    validator - the Validator to use (optional)
  - PayloadMethodArgumentResolver
```
public PayloadMethodArgumentResolver(MessageConverter messageConverter,
                                     @Nullable
                                     Validator validator,
                                     boolean useDefaultResolution)
```
    Create a new PayloadArgumentResolver with the given MessageConverter and Validator.
    Parameters:
    messageConverter - the MessageConverter to use (required)
    validator - the Validator to use (optional)
    useDefaultResolution - if "true" (the default) this resolver supports all parameters; if "false" then only arguments with the @Payload annotation are supported.
- Method Detail
  - supportsParameter
```
public boolean supportsParameter(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
```
@Nullable
public Object resolveArgument(MethodParameter parameter,
                              Message<?> message)
                       throws 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:
    parameter - the method parameter to resolve. This parameter must have previously been passed to HandlerMethodArgumentResolver.supportsParameter(org.springframework.core.MethodParameter) which must have returned true.
    message - the currently processed message
    Returns:
    the resolved argument value, or null
    Throws:
    Exception - in case of errors with the preparation of argument values
  - isEmptyPayload
```
protected boolean isEmptyPayload(@Nullable
                                 Object payload)
```
    Specify if the given payload is empty.
    Parameters:
    payload - the payload to check (can be null)
  - resolveTargetClass
```
protected Class<?> resolveTargetClass(MethodParameter parameter,
                                      Message<?> message)
```
    Resolve the target class to convert the payload to.
    By default this is simply MethodParameter.getParameterType() but that can be overridden to select a more specific target type after also taking into account the "Content-Type", e.g. return String if target type is Object and "Content-Type:text/**".
    Parameters:
    parameter - the target method parameter
    message - the message being processed
    Returns:
    the target type to use
    Since:
    5.2
  - validate
```
protected void validate(Message<?> message,
                        MethodParameter parameter,
                        Object target)
```
    Validate the payload if applicable.
    The default implementation checks for @javax.validation.Valid, Spring's Validated, and custom annotations whose name starts with "Valid".
    Parameters:
    message - the currently processed message
    parameter - the method parameter
    target - the target payload object
    Throws:
    MethodArgumentNotValidException - in case of binding errors

Class PayloadMethodArgumentResolver

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

PayloadMethodArgumentResolver

PayloadMethodArgumentResolver

PayloadMethodArgumentResolver

Method Detail

supportsParameter

resolveArgument

isEmptyPayload

resolveTargetClass

validate