SpringBoot统一数据返回格式的实现示例

public class ApiResponse<T> {
    private int status;
    private String message;
    private T data;

    public ApiResponse(int status, String message, T data) {
        this.status = status;
        this.message = message;
        this.data = data;
    }

    // Getters and Setters
}

@ControllerAdvice
public class GlobalResponseBodyAdvice implements ResponseBodyAdvice<Object> {

    @Override
    public boolean supports(MethodParameter returnType, Class converterType) {
        // 判断是否需要处理响应体
        return true;
    }

    @Override
    public Object beforeBodyWrite(Object body, MethodParameter returnType, MediaType selectedContentType,
                                  Class selectedConverterType, ServerHttpRequest request, ServerHttpResponse response) {
        // 包装响应体
        if (body instanceof ApiResponse) {
            return body;
        }
        return new ApiResponse<>(HttpStatus.OK.value(), "Success", body);
    }
}

@ControllerAdvice //添加完此注解后，此类随着springboot项目的启动而启动，并且会监控controller的异常.监听项目中所有的异常
@ResponseBody
public class MyExceptionAdvice {

    //这里的一场都是意外异常，并不是业务异常，业务异常后端controller会处理返回给前端.业务异常会和前端沟通好已规定的状态码返回。
    @ExceptionHandler(NullPointerException.class)
    public ApiResponse<String> doNullPointerException(NullPointerException e){
        ApiResponse<String> apiResponse = new ApiResponse<>(HttpStatus.INTERNAL_SERVER_ERROR.value(), e.getMessage(), null);
        return apiResponse;
    }

    // 默认的异常处理，当有有异常出现的时候，会先匹配子类的异常，当所有的异常都没有匹配的时候就会走这一条默认的一场路线业务。
    @ExceptionHandler(Exception.class)
    public ApiResponse<String> doException(Exception e){
        ApiResponse<String> apiResponse = new ApiResponse<>(HttpStatus.INTERNAL_SERVER_ERROR.value(), e.getMessage(), null);
        return apiResponse;
    }
}

@RestController
@RequestMapping("/user")
public class UserController {

    @RequestMapping("login")
    public String login(){
        Object obj = null;
        System.out.println(obj.hashCode());
        return  "这里是login";
    }

    @GetMapping("/data")
    public User getUserData() {
        // 这个方法会返回一个User对象
        User user = new User();
        user.setId(1);
        user.setName("张三");
        user.setEmail("zhangsan@example.com");
        return user;
    }

    @GetMapping("/success")
    public Integer getSuccessMessage() {
        // 这个方法会返回一个简单的字符串
        return 123456;
    }
}