spring-mvc - aop.AopInvocationException : Null return value from

Question

这是存储库:

@Query(value = "select u.balance from User u where u.name=:name")
float toGetBalance(@Param("name") String name);

这是DAO界面:

boolean checkBalance(String userName, float totalPrice);

这是服务

@Transactional(readOnly = true)
@Override
public boolean checkBalance(String userName, float totalPrice) {

    if (userRepository.toGetBalance(userName) < totalPrice) {

        return false;

    } else {

        return true;

    }

}

这是错误信息:

org.springframework.aop.AopInvocationException: Null return value from advice does not match primitive return type for: public abstract float com.repository.UserRepository.toGetBalance(java.lang.String)

余额类型是 float 的!

怎么了？

Answer 1

将存储库的签名更改为

@Query(value = "select u.balance from User u where u.name=:name")
Float toGetBalance(@Param("name") String name);

如果数据库中没有给定 null的用户，它将仅返回 name