HibernateException:当'hibernate.dialect'没有设置但是在没有问题的另一台机器上工作时,对DialectResolutionInfo的访问不能为null

时间:2016-03-23 23:00:31

标签: java hibernate jpa spring-boot

我让这个项目在另一台机器上完美运行。我决定在另一个上更多地处理它,我得到以下错误:

Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.services.contact.ContactService com.controller.ContactController.contactService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contactServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.repository.ContactRepository com.services.contact.ContactServiceImpl.contactRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contactRepository': Cannot create inner bean '(inner bean)#627d8516' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#627d8516': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [com/configuration/JpaConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManagerFactory]: Factory method 'entityManagerFactory' threw exception; nested exception is org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:573) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 22 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contactServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.repository.ContactRepository com.services.contact.ContactServiceImpl.contactRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contactRepository': Cannot create inner bean '(inner bean)#627d8516' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#627d8516': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [com/configuration/JpaConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManagerFactory]: Factory method 'entityManagerFactory' threw exception; nested exception is org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1192) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1116) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:545) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 24 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.repository.ContactRepository com.services.contact.ContactServiceImpl.contactRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contactRepository': Cannot create inner bean '(inner bean)#627d8516' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#627d8516': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [com/configuration/JpaConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManagerFactory]: Factory method 'entityManagerFactory' threw exception; nested exception is org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:573) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 35 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contactRepository': Cannot create inner bean '(inner bean)#627d8516' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#627d8516': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [com/configuration/JpaConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManagerFactory]: Factory method 'entityManagerFactory' threw exception; nested exception is org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:313) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:129) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1481) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1226) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1192) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1116) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:545) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 37 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#627d8516': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [com/configuration/JpaConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManagerFactory]: Factory method 'entityManagerFactory' threw exception; nested exception is org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:359) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:108) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.resolveConstructorArguments(ConstructorResolver.java:634) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:444) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1123) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1018) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:299) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 50 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [com/configuration/JpaConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManagerFactory]: Factory method 'entityManagerFactory' threw exception; nested exception is org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:599) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1123) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1018) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:351) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 58 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManagerFactory]: Factory method 'entityManagerFactory' threw exception; nested exception is org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:189) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 67 common frames omitted
Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.determineDialect(DialectFactoryImpl.java:104) ~[hibernate-core-4.3.11.Final.jar:4.3.11.Final]
    at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:71) ~[hibernate-core-4.3.11.Final.jar:4.3.11.Final]

我会尝试包含所有重要文件:

application.properties

spring.mail.host = stmp.gmail.com
spring.mail.username = ****.******@gmail.com 
spring.mail.password = password
spring.mail.port=25

spring.datasource.url= jdbc:mysql://localhost:3306/personalSite
spring.datasource.username=root

spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.jpa.hibernate.ddl-auto=update

JPA配置

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories("com.repository")
public class JpaConfig {

    @Bean
    public DataSource dataSource() {
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName("com.mysql.jdbc.Driver");
        dataSource.setUrl("jdbc:mysql://localhost:3306/personalSite");
        dataSource.setUsername("root");
        return dataSource;
    }

    @Bean
    public JpaVendorAdapter jpaVendorAdapter() {
        HibernateJpaVendorAdapter jpaVendorAdapter = new HibernateJpaVendorAdapter();

        jpaVendorAdapter.setDatabase(Database.MYSQL);
        jpaVendorAdapter.setGenerateDdl(true);
        jpaVendorAdapter.setShowSql(true);
        jpaVendorAdapter.setDatabasePlatform("org.hibernate.dialect.MySQL5Dialect");

        return jpaVendorAdapter;
    }

    @Bean
    public EntityManagerFactory entityManagerFactory() {

        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        vendorAdapter.setGenerateDdl(true);

        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setJpaVendorAdapter(vendorAdapter);
        factory.setPackagesToScan("com.model");
        factory.setDataSource(dataSource());
        factory.afterPropertiesSet();

        return factory.getObject();
    }

    @Bean
    public PlatformTransactionManager transactionManager() {

        JpaTransactionManager txManager = new JpaTransactionManager();
        txManager.setEntityManagerFactory(entityManagerFactory());
        return txManager;
    }

    @Bean
    public HibernateJpaSessionFactoryBean sessionFactory(EntityManagerFactory emf) {
        HibernateJpaSessionFactoryBean factory = new HibernateJpaSessionFactoryBean();
        factory.setEntityManagerFactory(emf);
        return factory;
    }

}

ContactServiceImpl
@Component
public class ContactServiceImpl implements ContactService {

    @Autowired
    StmpMailSender stmpMailSender;

    @Autowired
    ContactRepository contactRepository;

    private String sendTo = "drew.jocham@gmail.com";

    @Override
    public void emailForm(Contact contact) {

        System.out.println("----------------------------------");
        System.out.println("I got the following from the form:");
        System.out.println(contact.getId());
        System.out.println(contact.getName());
        System.out.println(contact.getLastName());
        System.out.println(contact.getEmail());
        System.out.println(contact.getSubject());
        System.out.println(contact.getMessage());
        System.out.println("----------------------------------");

       // stmpMailSender.send(sendTo,contact.getSubject(),contact.getMessage(),contact.getEmail());

    }

    @Override
    public void submitFormToDatabase(Contact contact){

        contactRepository.save(contact);
    }

}

存储库

public interface ContactRepository extends CrudRepository<Contact,Long> {

    Contact save(Contact contact);

}

-----------------更新1 -----------------

我注意到这个非常明显的错误,但仍然感到困惑,因为我将其命名为数据库personalSite,并且我创建的表格与实体相同

2016-03-23 20:29:03.963  INFO 36929 --- [           main] org.hibernate.Version                    : HHH000412: Hibernate Core {4.3.11.Final}
2016-03-23 20:29:03.965  INFO 36929 --- [           main] org.hibernate.cfg.Environment            : HHH000206: hibernate.properties not found
2016-03-23 20:29:03.967  INFO 36929 --- [           main] org.hibernate.cfg.Environment            : HHH000021: Bytecode provider name : javassist
2016-03-23 20:29:04.226  INFO 36929 --- [           main] o.hibernate.annotations.common.Version   : HCANN000001: Hibernate Commons Annotations {4.0.5.Final}
2016-03-23 20:29:04.479  WARN 36929 --- [           main] o.h.e.jdbc.internal.JdbcServicesImpl     : HHH000342: Could not obtain connection to query metadata : Unknown database 'personalsite'

1 个答案:

答案 0 :(得分:1)

代码中缺少Hibernate.Dialect。下面是配置类的entityManagerFactory()方法下的修复。

factory.setJpaProperties(additionalProperties()); 帮助您添加Hibernate.Dialect。由于你的数据库是mySQL,mySQL的hibernate.dialect是&#34; org.hibernate.dialect.MySQLDialect&#34;

@Bean
    public EntityManagerFactory entityManagerFactory() {

        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        vendorAdapter.setGenerateDdl(true);

        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setJpaVendorAdapter(vendorAdapter);
        factory.setPackagesToScan("com.model");
        factory.setDataSource(dataSource());
        factory.afterPropertiesSet();
        factory.setJpaProperties(additionalProperties());
        return factory.getObject();
    }


Properties additionalProperties() {
        Properties properties = new Properties();       
        properties.setProperty("hibernate.dialect", "org.hibernate.dialect.MySQLDialect");
        return properties;
    }