expected at least 1 bean which qualifies as autowire candidate for this dependency.

Caused by: : No qualifying bean of type [] found for dependency []: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}
    at (:1398)
    at (:1051)
    at (:1018)
    at $(:643)

    ... 28 more

原因：bean没有注入。

<!-- 自动扫描(自动注入) -->
    <context:component-scan base-package="" />

@Service("userService")
public class UserServiceImpl implements IUserService {
    private UserMapper userMapper;
    
    public UserMapper getUserMapper() {
        return userMapper;
    }
    @Autowired
    public void setUserMapper(UserMapper userMapper) {
         = userMapper;
    }

解决：

<!-- 自动扫描(自动注入) -->
    <context:component-scan base-package="" />