@ControllerAdvice,ResponseBodyAdvice統合処理戻り値/応答体

ResponseBodyAdviceはspring 4.1の新しい特性であり、その役割は応答体が書く前にいくつかの処理を行うことである.たとえば、戻り値の変更、暗号化などです.
私がプロジェクトで使用している@ControllerAdvice,ResponseBodyAdviceの目的は,各リクエストの戻りjsonに属性値を変更することである.
ResponseBodyAdviceインタフェースのソース:

package org.springframework.web.servlet.mvc.method.annotation;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
/**
 * Allows customizing the response after the execution of an {@code @ResponseBody}
 * or an {@code ResponseEntity} controller method but before the body is written
 * with an {@code HttpMessageConverter}.
Implementations may be may be registered directly with
 * {@code RequestMappingHandlerAdapter} and {@code ExceptionHandlerExceptionResolver}
 * or more likely annotated with {@code @ControllerAdvice} in which case they
 * will be auto-detected by both.
 *
 * @author Rossen Stoyanchev
 * @since 4.1
 */
public interface ResponseBodyAdvice {
    /**
     * Whether this component supports the given controller method return type
     * and the selected {@code HttpMessageConverter} type.
     * @param returnType the return type
     * @param converterType the selected converter type
     * @return {@code true} if {@link #beforeBodyWrite} should be invoked, {@code false} otherwise
     */
    boolean supports(MethodParameter returnType, Class> converterType);

    /**
     * Invoked after an {@code HttpMessageConverter} is selected and just before
     * its write method is invoked.
     * @param body the body to be written
     * @param returnType the return type of the controller method
     * @param selectedContentType the content type selected through content negotiation
     * @param selectedConverterType the converter type selected to write to the response
     * @param request the current request
     * @param response the current response
     * @return the body that was passed in or a modified, possibly new instance
     */
    T beforeBodyWrite(T body, MethodParameter returnType, MediaType selectedContentType,
            Class> selectedConverterType,
            ServerHttpRequest request, ServerHttpResponse response);

}

実装例:

package com.xxx;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.http.server.ServletServerHttpRequest;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;
import com.xxx.Messages;
/**
 *       
 * @Description:TODO
 * @author lh
 * @time:2015-8-31   11:24:08
 */

@ControllerAdvice
public class MyResponseBodyAdvice implements ResponseBodyAdvice{

    @Override
    public Object beforeBodyWrite(Object returnValue, MethodParameter methodParameter,
            MediaType mediaType, Class clas, ServerHttpRequest serverHttpRequest,
            ServerHttpResponse serverHttpResponse) {
        //   ServerHttpRequest    ServletServerHttpRequest   HttpServletRequest  
        //ServletServerHttpRequest sshr=(ServletServerHttpRequest) serverHttpRequest;
        //     request                          ,    
        //HttpServletRequest request=   sshr.getServletRequest();

        //    returnValue        Message>                 
        // Messages         
       Messages> msg=(Messages>) returnValue;
        //       /   
        msg.setXXX("       ");
        //       
        return msg;
    }

    @Override
    public boolean supports(MethodParameter methodParameter, Class clas) {
        //         controller   
        String methodName=methodParameter.getMethod().getName(); 
        //    /            
        String method= "loginCheck"; //   
        //   
        return !method.equals(methodName);
    }
}

このようにして得られた処理済みの戻り値は、属性xxxの値がすべて「テスト修正戻り値」である.