org.springframework.web.method.support.HandlerMethodArgumentResolver.java Source code

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Here is the source code for org.springframework.web.method.support.HandlerMethodArgumentResolver.java

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/*
 * Copyright 2002-2014 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

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
 * @since 3.1
 * @see HandlerMethodReturnValueHandler
 */
public interface HandlerMethodArgumentResolver {

    /**
     * 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 {@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;

}