无法使用spring引导自动连接spring中的字段

在过去的4-5天里，我一直在努力想办法解决

spring&hibernate

的问题，我觉得自己几乎成了他们的……我真的很困惑，为什么会出现这些

自动连线

错误

我试图创建一个

restapi

，所以我选择了mvc模式

有人知道我为什么会犯这些错误吗？我在下面提供了我的设置和堆栈跟踪

控制器包：spring.Controller 编辑1 我尝试删除

@Repository（“userDAO”）

中的标签，并使其成为

@Repository

。正如其中一个答案所建议的那样

这没有改变任何事情

编辑2 这是我的主要课程：

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;


@SpringBootApplication
public class Main {
    private static final SessionFactory ourSessionFactory;
    private static final ServiceRegistry serviceRegistry;

    static {
        try {
            Configuration configuration = new Configuration();
            configuration.configure();

            serviceRegistry = new ServiceRegistryBuilder().applySettings(configuration.getProperties()).buildServiceRegistry();
            ourSessionFactory = configuration.buildSessionFactory(serviceRegistry);
        } catch (Throwable ex) {
            throw new ExceptionInInitializerError(ex);
        }
    }

    public static Session getSession() throws HibernateException {
        return ourSessionFactory.openSession();
    }

    public static void main(final String[] args) throws Exception {
        SpringApplication.run(Main.class, args);
    }
}

编辑3： 在尝试了m.deinum的解决方案之后，我得到了以下堆栈跟踪…删除daoImpl和abstractImpl是一个好主意。但我仍然不断地在创建名为X的bean时遇到这些错误：自动连接依赖项的注入失败了异常

调整代码以适应以下答案后的堆栈跟踪：

[WARNING] 
java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:483)
        at org.springframework.boot.maven.AbstractRunMojo$LaunchRunner.run(AbstractRunMojo.java:478)
        at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: spring.service.userService spring.controller.userController.userService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: hibernate.dao.userDAO spring.service.userServiceImpl.dao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [hibernate.dao.userDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
        at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772)
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839)
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538)
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:766)
        at org.springframework.boot.SpringApplication.createAndRefreshContext(SpringApplication.java:361)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:307)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1191)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1180)
        at spring.Main.main(Main.java:44)
        ... 6 more
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: spring.service.userService spring.controller.userController.userService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: hibernate.dao.userDAO spring.service.userServiceImpl.dao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [hibernate.dao.userDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:573)
        at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
        ... 23 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: hibernate.dao.userDAO spring.service.userServiceImpl.dao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [hibernate.dao.userDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
        at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1192)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1116)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014)
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:545)
        ... 25 more
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: hibernate.dao.userDAO spring.service.userServiceImpl.dao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [hibernate.dao.userDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:573)
        at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
        ... 36 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [hibernate.dao.userDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1373)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1119)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014)
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:545)
        ... 38 more

只需从中删除名称

@Repository("userDAO")
public class userDAOImpl extends AbstractDao<Integer, user> implements userDAO {

@Repository（“userDAO”）
公共类userDAOImpl扩展了AbstractDao，实现了userDAO{

成功

@Repository
public class userDAOImpl extends AbstractDao<Integer, user> implements userDAO {

@存储库
公共类userDAOImpl扩展了AbstractDao，实现了userDAO{

只需从

@Repository("userDAO")
public class userDAOImpl extends AbstractDao<Integer, user> implements userDAO {

@Repository（“userDAO”）
公共类userDAOImpl扩展了AbstractDao，实现了userDAO{

成功

@Repository
public class userDAOImpl extends AbstractDao<Integer, user> implements userDAO {

@存储库
公共类userDAOImpl扩展了AbstractDao，实现了userDAO{

这可能是由于您定义了多个

造成的。最新的

正在生效。从异常情况来看，Spring确实在实例化服务bean

只用

<context:component-scan base-package="spring.controller, hibernate.dao, hibernate.model,spring.service" /> 

---

这可能是由于您定义了多个

造成的。最新的

正在生效。从异常情况来看，Spring确实在实例化服务bean

只用

<context:component-scan base-package="spring.controller, hibernate.dao, hibernate.model,spring.service" /> 

---

对于初学者，当前您的

应用程序上下文.xml

非常无用。如果删除它，重新启动，您仍然会得到相同的异常。这是由于Spring Boot（默认情况下）的工作方式

您的

Main

类在

spring

包中定义。spring引导自动扫描此包及其所有子包。但是，您的dao等位于

hibernate

中，spring引导组件扫描未涵盖

要么添加

@ImportResource（“您的/applicationContext.xml的位置”）

，要么简单地将

@ComponentScan（{“spring”，“hibernate”}）

添加到主类中，要么将DAO移动到

spring

的子包中

您的代码也有缺陷，您使用的是Spring，然后使用Spring，不要自己配置hibernate。为此使用

LocalSessionFactoryBean

，让Spring为您处理所有这些

@SpringBootApplication
public class Main {   

    public static void main(final String[] args) throws Exception {
        SpringApplication.run(Main.class, args);
    }

    @Bean
    public LocalSessionFactoryBean sessionFactory() {
     return new LocalSessionFactoryBean();
    }
}

但是，与使用普通的Hibernate和滚动另一个抽象dao不同，我建议您删除所有这些。将JPA与Spring数据JPA一起使用，可以节省大量代码。（删除user

userDaoImpl

和

AbstractDao

及其附带的所有接口）

您的

userDao

看起来像

public interface userDao extends JpaRepository<User, Integer> {}

一般的建议是使用框架（首先阅读一些文档），而不是尝试新框架的旧方法

---

Pro提示：使用公认的命名约定

userserviceinpl

等。在Java语言中，这不是真正的定制，从大写字母开始

userserviceinpl

对于初学者来说，当前您的

applicationContext.xml

几乎毫无用处。如果删除它，重新启动，您仍然可以获得sam这是由于Spring引导（默认）的工作方式

您的

Main

类在

spring

包中定义。spring引导自动扫描此包及其所有子包。但是，您的dao等位于

hibernate

中，spring引导组件扫描未涵盖

要么添加

@ImportResource（“您的/applicationContext.xml的位置”）

，要么简单地将

@ComponentScan（{“spring”，“hibernate”}）

添加到主类中，要么将DAO移动到

spring

的子包中

您的代码也有缺陷，您使用的是Spring，然后使用Spring，不要自己配置hibernate。为此使用

LocalSessionFactoryBean

，让Spring为您处理所有这些

@SpringBootApplication
public class Main {   

    public static void main(final String[] args) throws Exception {
        SpringApplication.run(Main.class, args);
    }

    @Bean
    public LocalSessionFactoryBean sessionFactory() {
     return new LocalSessionFactoryBean();
    }
}

但是，与使用普通的Hibernate和滚动另一个抽象dao不同，我建议您删除所有这些。将JPA与Spring数据JPA一起使用，可以节省大量代码。（删除user

userDaoImpl

和

AbstractDao

及其附带的所有接口）

您的

userDao

看起来像

public interface userDao extends JpaRepository<User, Integer> {}

一般的建议是使用框架（首先阅读一些文档），而不是尝试新框架的旧方法

---

Pro提示：使用公认的命名约定

userserviceinpl

等。在Java land中不是真正的定制，请以大写字母

userserviceinpl

开始请在以下位置使用@Qualifier注释：

public class userController {
    @Autowired
    @Qualifier("userService")
    userService userService;

及

---

并检查。

请在以下位置使用@Qualifier注释：

public class userController {
    @Autowired
    @Qualifier("userService")
    userService userService;

及

---

然后检查。

您在哪个包中有

userDAOImpl

类？

hibernate.dao

-我在上面添加了包位置^^^^您在哪个包中有

userDAOImpl

类？

hibernate.dao

-我在上面添加了包位置^^^^不幸的是，这并没有修复它。在AbstractDao的构造函数中打印一些东西，如果没有显示任何内容，则说明DAO没有被实例化。没有打印任何内容…尽管我不确定为什么DAO没有被实例化。不确定，您的主应用程序类上可能缺少@ImportResource（“classpath:applicationContext.xml”）？您的服务类在同一pac中吗

@Service("userService")
@Transactional
public class userServiceImpl implements userService {
    @Autowired
    userDAO dao;

    public List<user> findAll() {
        return dao.findAll();
    }
    ...
}

public class userController {
    @Autowired
    @Qualifier("userService")
    userService userService;

@Service("userService")
@Transactional
public class userServiceImpl implements userService {
    @Autowired
    @Qualifier("userDAO")
    userDAO dao;