com.wesley_acheson.spring.BackingBeanValueResolver.java Source code

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Here is the source code for com.wesley_acheson.spring.BackingBeanValueResolver.java

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//   Copyright 2012 Wesley Acheson
//
//   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
//
//       http://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 com.wesley_acheson.spring;

import javax.servlet.http.HttpServletRequest;

import org.springframework.core.MethodParameter;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;

/**
 * Resolves method parameters which are annotated with {@link BackingBean}.
 * 
 * <b>Note:</b> Only works for Http requests.
 * 
 * @author Wesley Acheson
 * 
 */
public class BackingBeanValueResolver implements HandlerMethodArgumentResolver {

    /**
     * Constructor.
     */
    public BackingBeanValueResolver() {
    }

    /**
     * Implementation of
     * {@link HandlerMethodArgumentResolver#supportsParameter(MethodParameter)}
     * that returns true if the method parameter is annotatated with
     * {@link BackingBean}.
     */
    @Override
    public boolean supportsParameter(MethodParameter parameter) {
        return parameter.hasParameterAnnotation(BackingBean.class);
    }

    @Override
    public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
            NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
        return webRequest.getNativeRequest(HttpServletRequest.class)
                .getAttribute(BackingBeanUrlHandlerMapper.BACKING_BEAN_ATTRIBUTE);
    }

}