Package org.springframework.graphql.data.method.annotation.support

Class ArgumentMethodArgumentResolver

java.lang.Object

org.springframework.graphql.data.method.annotation.support.ArgumentMethodArgumentResolver

All Implemented Interfaces:

HandlerMethodArgumentResolver

public class ArgumentMethodArgumentResolver
extends Object
implements HandlerMethodArgumentResolver

Resolver for a method parameter that is annotated with @Argument. The specified raw argument value is obtained via DataFetchingEnvironment.getArgument(String) and bound to a higher level object via GraphQlArgumentBinder to match the target method parameter type.

This resolver also supports wrapping the target object with ArgumentValue if the application wants to differentiate between an input argument that was set to null vs not provided at all. When this wrapper type is used, the annotation is optional, and the name of the argument is derived from the method parameter name.

An ArgumentValue can also be nested within the object structure of an @Argument-annotated method parameter.

Since:

1.0.0

Author:

Rossen Stoyanchev, Brian Clozel

See Also:

• ArgumentsMethodArgumentResolver

Constructor Summary

Constructors

Constructor	Description
ArgumentMethodArgumentResolver(GraphQlArgumentBinder argumentBinder)

Method Summary

Modifier and Type	Method	Description
protected Object	doBind(DataFetchingEnvironment environment, String name, ResolvableType targetType)	Perform the binding with the configured binder.
GraphQlArgumentBinder	getArgumentBinder()	Return the configured GraphQlArgumentBinder.
Object	resolveArgument(MethodParameter parameter, DataFetchingEnvironment environment)	Resolve a method parameter to a value.
boolean	supportsParameter(MethodParameter parameter)	Whether this resolver supports the given MethodParameter.

Methods inherited from class java.lang.Object

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

Constructor Details

ArgumentMethodArgumentResolver

public ArgumentMethodArgumentResolver(GraphQlArgumentBinder argumentBinder)

Method Details

getArgumentBinder

public GraphQlArgumentBinder getArgumentBinder()

Return the configured GraphQlArgumentBinder.

Since:

1.3.0

supportsParameter

public boolean supportsParameter(MethodParameter parameter)

Description copied from interface: HandlerMethodArgumentResolver

Whether this resolver supports the given MethodParameter.

Specified by:

supportsParameter in interface HandlerMethodArgumentResolver

Parameters:

parameter - the method parameter to check for support

resolveArgument

public Object resolveArgument(MethodParameter parameter,
 DataFetchingEnvironment environment)
                       throws Exception

Description copied from interface: HandlerMethodArgumentResolver

Resolve a method parameter to a value.

Specified by:

resolveArgument in interface HandlerMethodArgumentResolver

Parameters:

parameter - the method parameter to resolve. This parameter must have previously checked via HandlerMethodArgumentResolver.supportsParameter(org.springframework.core.MethodParameter).

environment - the environment to use to resolve the value

Returns:

the resolved value, which may be null if not resolved; the value may also be a Mono if it requires asynchronous resolution.

Throws:

Exception - in case of errors with the preparation of argument values

doBind

@Nullable
protected Object doBind(DataFetchingEnvironment environment,
 String name,
 ResolvableType targetType)
                 throws BindException

Perform the binding with the configured binder.

Parameters:

environment - for access to the arguments

name - the name of an argument, or null to use the full map

targetType - the type of Object to create

Throws:

BindException

Since:

1.3.0