后端返回自定义HTTPStatus状态码的原理

public void save(BusUser busUser) {
    BusUser.checkAccountAndPasswordNotNull(busUser);
    if (busUserRepository.findByAccount(busUser.getAccount()).size() != 0) {
        throw new ApiException(ErrorType.SAVE_EXIST, "账号已经存在!");
    }
    // 存储的时候，服务器应该再次进行一次 hash，双重哈希，避免数据库泄漏，密码被人拿去登陆 todo
    busUserRepository.save(busUser);
    log.info("增加了一个用户:" + busUser.getAccount());
}

package pri.anarckk.common;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
import pri.anarckk.common.entity.ErrorEntity;
import pri.anarckk.common.exception.ApiException;

/**
 * Created by zzanar on 2019/6/1
 * 全局异常事件处理类
 */
@ControllerAdvice
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
    private final Logger logger = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    @ResponseBody
    @ExceptionHandler
    public ResponseEntity<ErrorEntity> handleException(Exception e) {
        if (e instanceof ApiException) {
            ApiException apiException = (ApiException) e;
            ErrorType code = apiException.getCode();
            apiException.error(logger);
            return new ResponseEntity<>(new ErrorEntity(code.code(), apiException.getMessage()), code.httpStatus());
        } else {
            logger.error(e.getMessage(), e);
            return new ResponseEntity<>(new ErrorEntity(ErrorType.UN_KNOW.code(), ErrorType.UN_KNOW.message()), ErrorType.UN_KNOW.httpStatus());
        }
    }
}