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package org.springframework.web.method.support;

import org.springframework.core.MethodParameter;
import org.springframework.lang.Nullable;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;

Strategy interface for resolving method parameters into argument values in the context of a given request.
Author:Arjen Poutsma
See Also:
Since:3.1
/** * Strategy interface for resolving method parameters into argument values in * the context of a given request. * * @author Arjen Poutsma * @since 3.1 * @see HandlerMethodReturnValueHandler */
public interface HandlerMethodArgumentResolver {
Whether the given method parameter is supported by this resolver.
Params:
  • parameter – the method parameter to check
Returns:true if this resolver supports the supplied parameter; false otherwise
/** * Whether the given {@linkplain MethodParameter method parameter} is * supported by this resolver. * @param parameter the method parameter to check * @return {@code true} if this resolver supports the supplied parameter; * {@code false} otherwise */
boolean supportsParameter(MethodParameter parameter);
Resolves a method parameter into an argument value from a given request. A ModelAndViewContainer provides access to the model for the request. A WebDataBinderFactory provides a way to create a WebDataBinder instance when needed for data binding and type conversion purposes.
Params:
  • parameter – the method parameter to resolve. This parameter must have previously been passed to supportsParameter which must have returned true.
  • mavContainer – the ModelAndViewContainer for the current request
  • webRequest – the current request
  • binderFactory – a factory for creating WebDataBinder instances
Throws:
  • Exception – in case of errors with the preparation of argument values
Returns:the resolved argument value, or null if not resolvable
/** * Resolves a method parameter into an argument value from a given request. * A {@link ModelAndViewContainer} provides access to the model for the * request. A {@link WebDataBinderFactory} provides a way to create * a {@link WebDataBinder} instance when needed for data binding and * type conversion purposes. * @param parameter the method parameter to resolve. This parameter must * have previously been passed to {@link #supportsParameter} which must * have returned {@code true}. * @param mavContainer the ModelAndViewContainer for the current request * @param webRequest the current request * @param binderFactory a factory for creating {@link WebDataBinder} instances * @return the resolved argument value, or {@code null} if not resolvable * @throws Exception in case of errors with the preparation of argument values */
@Nullable Object resolveArgument(MethodParameter parameter, @Nullable ModelAndViewContainer mavContainer, NativeWebRequest webRequest, @Nullable WebDataBinderFactory binderFactory) throws Exception; }