Spring 異常：BeanNotOfRequiredTypeException

Question

我有一個帶有 Postgres DB 的 SpringMVC 應用程序。 我嘗試添加休眠支持，但無法創建 DAO bean。

全棧跟蹤

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'studentController' defined in file [C:\Users\user\IdeaProjects\sql-jdbc-school_app\target\sqlJdbcSchoolApp\WEB-INF\classes\ua\com\foxminded\sqljdbcschool\controllers\menu_controllers\StudentController.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'hibernateStudentDao' is expected to be of type 'ua.com.foxminded.sqljdbcschool.dao.hibernate.HibernateStudentDao' but was actually of type 'jdk.proxy3.$Proxy64'
    org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:578)
    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:530)
    at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:170)
    at javax.servlet.GenericServlet.init(GenericServlet.java:158)
    at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1161)
    at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1010)
    at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4948)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5256)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:726)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:698)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:696)
    at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:1782)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:293)
    at java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:814)
    at java.management/com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:802)
    at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:460)
    at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:408)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:293)
    at java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:814)
    at java.management/com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:802)
    at java.management/com.sun.jmx.remote.security.MBeanServerAccessController.invoke(MBeanServerAccessController.java:472)
    at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1472)
    at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1310)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:712)
    at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1412)
    at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at java.rmi/sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:360)
    at java.rmi/sun.rmi.transport.Transport$1.run(Transport.java:200)
    at java.rmi/sun.rmi.transport.Transport$1.run(Transport.java:197)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:712)
    at java.rmi/sun.rmi.transport.Transport.serviceCall(Transport.java:196)
    at java.rmi/sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:587)
    at java.rmi/sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:828)
    at java.rmi/sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:705)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
    at java.rmi/sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:704)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
    at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'hibernateStudentDao' is expected to be of type 'ua.com.foxminded.sqljdbcschool.dao.hibernate.HibernateStudentDao' but was actually of type 'jdk.proxy3.$Proxy64'

2022 年 12 月 22 日 12:50:37.840 嚴重 [RMI TCP 連接 (3)-127.0.0.1] org.apache.catalina.core.StandardContext.loadOnStartup Servlet [dispatcher] 在 Web 應用程序 [] 中拋出 load() 異常 org. springframework.beans.factory.BeanNotOfRequiredTypeException：名為“hibernateStudentDao”的 Bean 應為“ua.com.foxminded.sqljdbcschool.dao.hibernate.HibernateStudentDao”類型，但實際上是“jdk.proxy3.$Proxy64”類型

用於休眠的 Spring 配置

@Configuration
@ComponentScan("ua.com.foxminded.sqljdbcschool")
@PropertySource("classpath:properties.properties")
@EnableTransactionManagement
public class SpringConfig {

    private final Environment environment;

    @Autowired
    public SpringConfig(Environment environment) {
        this.environment = environment;
    }

   
    @Bean
    public DataSource dataSource() {
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName(Objects.requireNonNull(environment.getProperty("driver")));
        dataSource.setUrl(environment.getProperty("url"));
        dataSource.setUsername(environment.getProperty("user"));
        dataSource.setPassword(environment.getProperty("password"));
        return dataSource;
    }

    private Properties hibernateProperties() {
        Properties properties = new Properties();
        properties.put("hibernate.dialect", environment.getRequiredProperty("hibernate.dialect"));
        properties.put("hibernate.show_sql", environment.getRequiredProperty("hibernate.show_sql"));
        return properties;
    }

    @Bean
    public LocalSessionFactoryBean sessionFactory() {
        LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();
        sessionFactory.setDataSource(dataSource());
        sessionFactory.setPackagesToScan("ua.com.foxminded.sqljdbcschool.dto");
        sessionFactory.setHibernateProperties(hibernateProperties());
        return sessionFactory;
    }

    @Bean
    public PlatformTransactionManager hibernateTransactionManager() {
        HibernateTransactionManager transactionManager = new HibernateTransactionManager();
        transactionManager.setSessionFactory(sessionFactory().getObject());
        return transactionManager;
    }
}

道類

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;
import ua.com.foxminded.sqljdbcschool.dao.StudentDao;
import ua.com.foxminded.sqljdbcschool.dto.CourseDTO;
import ua.com.foxminded.sqljdbcschool.dto.StudentDTO;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

@Repository
public class HibernateStudentDao implements StudentDao {

    private final SessionFactory sessionFactory;

    @Autowired
    public HibernateStudentDao(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
    }

    @Override
    @Transactional
    public void create(StudentDTO student) {
        Session session = sessionFactory.getCurrentSession();
        session.persist(student);
    }

    @Override
    @Transactional
    public List<StudentDTO> getAll() {
        Session session = sessionFactory.getCurrentSession();
        return session.createQuery(" select s from StudentDTO s", StudentDTO.class).getResultList();
    }

    @Override
    @Transactional
    public StudentDTO searchById(Integer id) {
        Session session = sessionFactory.getCurrentSession();
        return session.get(StudentDTO.class, id);
    }

    @Override
    @Transactional
    public void delete(StudentDTO student) {
        Session session = sessionFactory.getCurrentSession();
        session.remove(student);
    }

控制器

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import ua.com.foxminded.sqljdbcschool.dao.CourseDao;
import ua.com.foxminded.sqljdbcschool.dao.StudentDao;
import ua.com.foxminded.sqljdbcschool.dao.hibernate.HibernateCourseDao;
import ua.com.foxminded.sqljdbcschool.dao.hibernate.HibernateStudentDao;
import ua.com.foxminded.sqljdbcschool.dto.CourseDTO;
import ua.com.foxminded.sqljdbcschool.dto.StudentDTO;

import java.util.ArrayList;
import java.util.List;

@Controller
@RequestMapping("/menu/")
public class StudentController {
    private static final String REDIRECT_MENU_SUCCESS = "redirect:success";
    private final StudentDao studentDao;
    private final CourseDao courseDao;

    @Autowired
    public StudentController(HibernateStudentDao studentDao, HibernateCourseDao courseDao) {
        this.studentDao = studentDao;
        this.courseDao = courseDao;
    }

StudentDao接口

public interface StudentDao {

 void create (StudentDTO student);

 List<StudentDTO> getAll();

 StudentDTO searchById(Integer id);

 void delete (StudentDTO student);

 void addStudentToGroup(StudentDTO student, Integer groupId);

 void addStudentToCourse(StudentDTO student, CourseDTO course);

 void deleteStudentFromCourse(StudentDTO student, CourseDTO course);

 Map<Integer, Integer> searchGroupsByStudentCount(Integer studentCount);

 void batchCreate(List<StudentDTO> students);

 void batchAddStudentToGroup(List<StudentDTO> students);

我絕對不明白如何解決它。

Answer 1

@Repository注釋標記接口，而不是實現。 如果您想要自定義實現，則必須遵循一些預定義的步驟（包括相關組件的命名/位置/標記），為此請參閱 JPA 文檔。 你可以從這篇文章開始。

Answer 2

@M.Deinum 的決定。

通過在 SpringConfig 的 EnableTransactionManagement Annotation 添加參數 proxyTargetClass = true 解決了這個問題。

@EnableTransactionManagement(proxyTargetClass = true)

此外，我將 Controller 構造函數中的參數從 Impl 更改為與 Qualifier 接口