spring boot 给返回值加状态 BaseData

JavaWeb开发中，需要给前端返回的数据加上一些头部的状态信息，来表示请求成功或失败的状态原因

一、数据添加状态信息

　　1.新建BaseData

public class BaseData<T> {

    private String returnCode;
    private String returnMsg;
    private T data;
    //其他的get set toString 方法略
}

　　2.定义工具类：

public final class ReturnInfoUtils {
    private ReturnInfoUtils(){}
    //返回状态信息
    public static final String SUCCESSCODE="100";
    public static final String SUCCESSMSG="操作成功";
    public static final String FAILCODE="500";
    public static final String FAILMSG="操作失败";
}

　　3.定义注解：

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface ReturnWrapper {

    String returnCode() default ReturnInfoUtils.SUCCESSCODE;
    String returnMsg() default  ReturnInfoUtils.SUCCESSMSG;
}

　　4.新建类继承AbstractMappingJacksonResponseBodyAdvice并重写一个切面方法beforeBodyWriteInternal

　　

 package com.zpark.tools.interceptor;

 import com.zpark.response.ReturnDto;
 import org.springframework.core.MethodParameter;
 import org.springframework.http.MediaType;
 import org.springframework.http.converter.json.MappingJacksonValue;
 import org.springframework.http.server.ServerHttpRequest;
 import org.springframework.http.server.ServerHttpResponse;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
 import org.springframework.web.servlet.mvc.method.annotation.AbstractMappingJacksonResponseBodyAdvice;

 /**
  * @author cosmo
  * @Title: CommonWrsControllerAdvice
  * @ProjectName
  * @Description: TODO
  * @date
  */
 @RestControllerAdvice
 public class CommonWrsControllerAdvice extends AbstractMappingJacksonResponseBodyAdvice {
     @Override
     protected void beforeBodyWriteInternal(MappingJacksonValue mappingJacksonValue, MediaType mediaType, MethodParameter methodParameter, ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse) {
         if (methodParameter.getMethod().isAnnotationPresent(RerutnWrapper.class)) {
             mappingJacksonValue.setValue(getWrapperResponse(methodParameter,serverHttpRequest, mappingJacksonValue.getValue()));
         }
     }

     private ReturnDto getWrapperResponse(MethodParameter returnType, ServerHttpRequest req, Object data) {
         ReturnWrapper wrapper=returnType.getMethod().getAnnotation(ReturnWrapper.class);
         BaseData = new BaseData();
         returnDto.setData(data);
         returnDto.setreturnCode(wrapper.ReturnCode());
         return returnDto;
     }
 }

就可以用注解来返回的数据

   /**
      * 测试.
      *
      * @return the attachment info
      */
     @ResponseBody
     @RequestMapping(value = {"test"})
     @RestWrapper(msg = ReturnInfoUtils.GETSUCCESS)
     public List<Employee> test() {
         List<Employee> employeeList=new ArrayList<>();
         Employee employee=new Employee();
         employee.setName("lisi");
         employeeList.add(employee);
         return employeeList;
     }
  

返回数据：

{
    "returnCode": "SUCCESS",
    "returnMsg": "操作成功",
    "data": [
        {
            "name": "lisi"
        }
    ]
}