无法解压缩到请求的类型[javax.sql.DataSource]

Question

我想在spring boot和hibernate 5.2.6中使用sessionfactory，在尝试了一些解决方案后，我尝试使用LocalSessionFactoryBuilder，但是我遇到了这个异常。我的数据源被spring boot注入。我不知道为什么

@Configuration
@EnableTransactionManagement
public class DatabaseConfiguration {

    @Inject
    public DataSource dataSource;

    @Inject
    public JpaProperties prop;

    @Bean
    public SessionFactory sessionFactory() {
        LocalSessionFactoryBuilder builder = new LocalSessionFactoryBuilder(dataSource);
        builder.scanPackages("or.roshan");
        builder.setProperties(getHibernateProperties());
        return builder.buildSessionFactory();
    }


    private Properties getHibernateProperties() {
        Properties properties = new Properties();
        properties.put("hibernate.show_sql", "true");
        properties.put("hibernate.dialect", "org.hibernate.dialect.MySQL5Dialect");
        properties.put("hibernate.current_session_context_class", "org.springframework.orm.hibernate5.SpringSessionContext");
        return properties;
    }


    @Bean
    public HibernateTransactionManager transactionManager(@Autowired SessionFactory sessionFactory) {
        HibernateTransactionManager transactionManager = new HibernateTransactionManager();
        transactionManager.setSessionFactory(sessionFactory);
        return transactionManager;
    }

}

我得到了这个例外

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager' defined in class path resource [org/roshan/framework/config/DatabaseConfiguration.class]: Invocation of init method failed; nested exception is org.hibernate.service.UnknownUnwrapTypeException: Cannot unwrap to requested type [javax.sql.DataSource]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1628)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483)
    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:761)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:866)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:737)
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:370)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:314)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151)
    at org.roshan.uaa.UaaApplication.main(UaaApplication.java:20)
    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:498)
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49)
Caused by: org.hibernate.service.UnknownUnwrapTypeException: Cannot unwrap to requested type [javax.sql.DataSource]
    at org.hibernate.engine.jdbc.connections.internal.UserSuppliedConnectionProviderImpl.unwrap(UserSuppliedConnectionProviderImpl.java:38)
    at org.springframework.orm.hibernate5.SessionFactoryUtils.getDataSource(SessionFactoryUtils.java:198)
    at org.springframework.orm.hibernate5.HibernateTransactionManager.afterPropertiesSet(HibernateTransactionManager.java:353)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624)
    ... 21 common frames omitted

Answer 1

我不知道你从哪里得到的建议，但在我看来很奇怪。如果要公开SessionFactory，应该执行如下操作：

@Configuration
public class MyConfig {

   @Bean
   public SessionFactory sessionFactory(EntityManagerFactory factory) {
     if (factory.unwrap(SessionFactory.class) == null) {
       throw new NullPointerException("factory is not a hibernate factory");
     }
     return entityManagerFactory.unwrap(SessionFactory.class);
   }
}