即使@Autowire和@ repository @ service已正确配置，也会引发NoSuchBeanDefinitionException

Question

我的控制器类：

@Controller
public class UsersController
{
    @Autowired
    TechRequestService techrequestservices;

@RequestMapping(value="/service_request", method=RequestMethod.POST)
    public @ResponseBody  Map<String,Object> SaveServiceRequest(@Valid Servicerequest servicerequest,BindingResult result){
        Map<String,Object> map = new HashMap<String,Object>();

        Object obj=new Object();
            if(result.hasErrors())
            {  
                for (Object object : result.getAllErrors()) {
                    if(object instanceof FieldError) {
                        FieldError fieldError = (FieldError) object;

                     obj= (fieldError.getDefaultMessage());
                    }
                map.put("status","400");
                map.put("message",obj);
                return map;
            }}
            techrequestservices.save_servicerequest(servicerequest);
            map.put("status","200");
            map.put("message","Your record have been saved successfully"); 
            return map;
            }

}

我的服务实现类：

@Service

    public class TechRequestServiceImpl implements TechRequestService{
        @Autowired
        TechRequestServiceDao techrequestservicedao;

        public boolean save_servicerequest(Servicerequest servicerequest) {
            return techrequestservicedao.save_servicerequest(servicerequest);
        }

        public List<Servicerequest> list() {
            // TODO Auto-generated method stub
            return techrequestservicedao.list();
        }



    }

我的DaoImpl课程：

@Repository
@Transactional
public class TechRequestServiceDaoImpl implements TechRequestService {

    @Autowired
SessionFactory session;

    @Override
    public boolean save_servicerequest(Servicerequest servicerequest) {
        // TODO Auto-generated method stub
        session.getCurrentSession().saveOrUpdate(servicerequest);
        return true;
    }

    @Override
    public List<Servicerequest> list() {

            return session.getCurrentSession().createQuery("from Search_type_case").list();

    }
}

请求来自ajax，并且pojo变量正在初始化它们的值，因为我通过在pojos的setter方法中放置print语句来确认它。异常的完整堆栈跟踪如下：

SEVERE: Exception sending context initialized event to listener instance of class

[org.springframework.web.context.ContextLoaderListener] org.springframework.beans.factory.BeanCreationException：创建名为'usersController'的bean时出错：注入自动连接的依赖项失败;嵌套异常是org.springframework.beans.factory.BeanCreationException：无法自动装配字段：com.servicesapi.TechRequestService com.controllers.UsersController.techrequestservices;嵌套异常是org.springframework.beans.factory.BeanCreationException：创建名为'techRequestServiceImpl'的bean时出错：注入自动连接的依赖项失败;嵌套异常是org.springframework.beans.factory.BeanCreationException：无法自动装配字段：com.daoapi.TechRequestServiceDao com.servicesimpl.TechRequestServiceImpl.techrequestservicedao;嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有为依赖项找到类型为[com.daoapi.TechRequestServiceDao]的限定bean：预期至少有一个bean可以作为此依赖项的autowire候选者。依赖注释：{org.springframework.beans.factory.annotation.Autowired（required = true）}位于org.springframework.beans的org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:334）。在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean的org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:543）上的factory.support.AbstractAutowireCapableBeanFactory.populateBean（AbstractAutowireCapableBeanFactory.java:1214）位于org.springframework.beans.factory.support.AbstractBeanFactory $ 1.getObject（AbstractBeanFactory.java:306）的org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton（DefaultSingletonBeanRegistry.java:230）处的AbstractAutowireCapableBeanFactory.java:482） org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean（AbstractBeanFactory.java ：302）在org.springframework的org.springframework.beans.factory.support.AbstractBeanFactory.getBean（AbstractBeanFactory.java:197）org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons（DefaultListableBeanFactory.java:772）。 context.support.AbstractApplicationContext.finishBeanFactoryInitialization（AbstractApplicationContext.java:839）org.springframework.context.support.AbstractApplicationContext.refresh（AbstractApplicationContext.java:538）org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext（ContextLoader.java： 444）org.springframework.web.context.ContextLoader.initWebApplicationContext（ContextLoader.java:326）atg.apringframework.web.context.ContextLoaderListener.contextInitialized（ContextLoaderListener.java:107）at org.apache.catalina.core.StandardContext .listenerStart（StandardContext.java:4792）位于org.apache.catali的org.apache.catalina.core.StandardContext.startInternal（StandardContext.java:5256） na.util.LifecycleBase.start（LifecycleBase.java:150）位于org.apache.catalina.core.ContainerBase $ StartChild.call（ContainerBase.java:1421）org.apache.catalina.core.ContainerBase $ StartChild.call（ ContainerBase.java:1411）at java.util.concurrent.TutureTask.run（Unknown Source）at java.util.concurrent.ThreadPoolExecutor.runWorker（Unknown Source）at java.util.concurrent.ThreadPoolExecutor $ Worker.run（Unknown Source）在java.lang.Thread.run（未知来源）

Answer 1

TechRequestServiceImpl和TechRequestServiceDaoImpl都实现了TechRequestService，因此在上下文中有两种类型为TechRequestService的bean，但没有类型：TechRequestServiceDao。要修复：TechRequestServiceDaoImpl应该实现TechRequestServiceDao

Answer 2

您的Component-Scan是否设置正确扫描给定路径内的包？尝试在component-scan中设置spring xml configuration以扫描相关包，如下所示：

<context:component-scan base-package="com.main"/> 

你的dao，service和controller包位于com.main内。这将扫描com.main下的所有文件，同时检查bean defising。