SpringBoot 统一接口数据返回格式实战方案

import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.SneakyThrows;
import org.springframework.beans.factory.annotation.Autowired;
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.web.bind.annotation.ControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;
import springbook.model.Result;

@ControllerAdvice
public class ResponseAdvice implements ResponseBodyAdvice {
    @Autowired
    private ObjectMapper objectMapper;

    @Override
    public boolean supports(MethodParameter returnType, Class converterType) {
        return true;
    }

    @SneakyThrows
    @Override
    public Object beforeBodyWrite(Object body, MethodParameter returnType, MediaType selectedContentType, Class selectedConverterType, ServerHttpRequest request, ServerHttpResponse response) {
        if (body instanceof Result) {
            return body;
        }
        // 针对 String 类型，先转为 JSON 字符串再包装
        if (body instanceof String) {
            return objectMapper.writeValueAsString(Result.success(body));
        }
        return Result.success(body);
    }
}

经过上述调整，无论返回何种类型，最终接口都会返回统一的 JSON 结构。

这样做的好处

统一返回格式不仅仅是为了好看，更是工程化的需要。它能显著降低前后端的沟通成本，因为双方只需约定一种数据结构；同时也方便后端维护，一旦需要增加错误码或时间戳，只需修改拦截器一处即可生效，避免了散落在各个业务方法中的重复代码。