java - 没有定义类型为[service.NewsServiceImpl]的合格Bean

我在Spring MVC中出错。

Exception in thread "main" org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [service.NewsServiceImpl] is defined
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:373)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:333)
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1088)
at controller.Testing.main(Testing.java:24)

NewsDAImpl代码为：

@Repository
public class NewsDAImpl implements NewsDA {

@PersistenceContext
private EntityManager context;

@Override
public News ... Some Other Codes

我的NewsServiceImpl类：

@Service
@Transactional
public class NewsServiceImpl implements NewsService{

@Autowired
private NewsDAImpl newsDa;

@Override
public News ... Some Other Codes

我编写的控制器具有静态void main，仅用于测试。
在那我写道：

ApplicationContext context = new AnnotationConfigApplicationContext(ProjectConfig.class);

然后我只是用getBean方法获取新闻服务：

NewsServiceImpl service = context.getBean(NewsServiceImpl.class);

最佳答案

更改

NewsServiceImpl service = context.getBean(NewsServiceImpl.class);

至

NewsService service = context.getBean(NewsService.class);

您已经用NewServiceImpl注释了@Transactional，因此默认情况下spring将创建一个代理，该代理当然实现NewsService而不是NewsServiceImpl。