springboot接口自定义返回包装数据

1:springboot web项目接口返回是基本对象类型，现在封装返回对象数据

org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor#handleReturnValue

这个类处理接口返回数据，所以新增实现HandlerMethodReturnValueHandler类，在默认处理handler之前，就可以处理接口返回值增加封装类

下面是具体实现

ApiResponseHandlerMethodReturnValueHandler

public class ApiResponseHandlerMethodReturnValueHandler implements HandlerMethodReturnValueHandler {

    private MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
    @Override
    public boolean supportsReturnType(MethodParameter returnType) {

        return (AnnotatedElementUtils.hasAnnotation(returnType.getContainingClass(), ResponseBody.class) || returnType.hasMethodAnnotation(ResponseBody.class)
                && ApiResponse.class.equals(returnType.getParameterType()));

    }

    @Override
    public void handleReturnValue(Object returnValue, MethodParameter returnType, ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {
        mavContainer.setRequestHandled(true);

        ApiResponse apiResponse = ApiResponse.ok(returnValue);

        HttpServletResponse response = (HttpServletResponse) webRequest.getNativeResponse();

        response.addHeader("v","3");

        ServletServerHttpResponse servletServerHttpResponse =createOutputMessage(webRequest);
        converter.write(apiResponse, MediaType.APPLICATION_JSON,servletServerHttpResponse);

    }

    protected ServletServerHttpResponse createOutputMessage(NativeWebRequest nativeWebRequest){

        HttpServletResponse response = nativeWebRequest.getNativeResponse(HttpServletResponse.class);

        Assert.state(response!=null,"no HttpServletResponse");
        return new ServletServerHttpResponse(response);
    }
}

2:配置WebMvcConfiguration

@Configuration
public class WebMvcConfiguration {


    @Autowired
    public void resetRequestMappingHandlerAdapter(RequestMappingHandlerAdapter requestMappingHandlerAdapter){
        List<HandlerMethodReturnValueHandler> handlerMethodReturnValueHandlers = requestMappingHandlerAdapter.getReturnValueHandlers();
        List<HandlerMethodReturnValueHandler> newHandlerMethodReturnValueHandlers =  new ArrayList(handlerMethodReturnValueHandlers);

        newHandlerMethodReturnValueHandlers.add(0,new ApiResponseHandlerMethodReturnValueHandler());
        requestMappingHandlerAdapter.setReturnValueHandlers(newHandlerMethodReturnValueHandlers);
    }
}

3:postman请求

1.png

github代码地址 https://github.com/knowledgeAlan/trail-excise-demo/tree/customer-response-format