java - 组织.hibernate.HibernateException : Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set

Question

我正在尝试运行一个通过 spring-jpa 使用 hibernate 的 spring-boot 应用程序，但出现此错误:

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)
        at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:71)
        at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:205)
        at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:111)
        at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:234)
        at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:206)
        at org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1885)
        at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1843)
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:850)
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:843)
        at org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl(ClassLoaderServiceImpl.java:398)
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:842)
        at org.hibernate.jpa.HibernatePersistenceProvider.createContainerEntityManagerFactory(HibernatePersistenceProvider.java:152)
        at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:336)
        at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:318)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1613)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1550)
        ... 21 more

我的 pom.xml 文件是这样的:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.1.8.RELEASE</version>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-web</artifactId>
       </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-config</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-taglibs</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>commons-dbcp</groupId>
        <artifactId>commons-dbcp</artifactId>
    </dependency>
</dependencies>

我的 hibernate 配置是(方言配置在这个类的最后一个方法中):

@Configuration
@EnableTransactionManagement
@ComponentScan({ "com.spring.app" })
public class HibernateConfig {

   @Bean
   public LocalSessionFactoryBean sessionFactory() {
      LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();

      sessionFactory.setDataSource(restDataSource());
      sessionFactory.setPackagesToScan(new String[] { "com.spring.app.model" });
      sessionFactory.setHibernateProperties(hibernateProperties());

      return sessionFactory;
   }

   @Bean
   public DataSource restDataSource() {
      BasicDataSource dataSource = new BasicDataSource();

      dataSource.setDriverClassName("org.postgresql.Driver");
      dataSource.setUrl("jdbc:postgresql://localhost:5432/teste?charSet=LATIN1");
      dataSource.setUsername("klebermo");
      dataSource.setPassword("123");

      return dataSource;
   }

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

   @Bean
   public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {
      return new PersistenceExceptionTranslationPostProcessor();
   }

   Properties hibernateProperties() {
      return new Properties() {
         /**
         * 
         */
        private static final long serialVersionUID = 1L;

        {
            setProperty("hibernate.hbm2ddl.auto", "create");
            setProperty("hibernate.show_sql", "false");
            setProperty("hibernate.dialect", "org.hibernate.dialect.PostgreSQLDialect");
         }
      };
   }
}

我做错了什么？

Answer 1

首先删除所有配置，Spring Boot 将为您启动它。

确保您的类路径中有一个 application.properties 并添加以下属性。

spring.datasource.url=jdbc:postgresql://localhost:5432/teste?charSet=LATIN1
spring.datasource.username=klebermo
spring.datasource.password=123

spring.jpa.database-platform=org.hibernate.dialect.PostgreSQLDialect
spring.jpa.show-sql=false
spring.jpa.hibernate.ddl-auto=create

如果您确实需要访问 SessionFactory 并且基本上是针对相同的数据源，那么您可以执行以下操作(也记录在案 here 虽然是针对 XML，而不是 JavaConfig)。

@Configuration        
public class HibernateConfig {

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

这样你就有了一个 EntityManagerFactory 和一个 SessionFactory。

更新:从 Hibernate 5 开始，SessionFactory 实际上扩展了 EntityManagerFactory。因此，要获得 SessionFactory，您可以简单地将 EntityManagerFactory 转换为它或使用 unwrap 方法来获得一个。

public class SomeHibernateRepository {

  @PersistenceUnit
  private EntityManagerFactory emf;

  protected SessionFactory getSessionFactory() {
    return emf.unwrap(SessionFactory.class);
  }

}

假设您有一个带有 main 方法和 @EnableAutoConfiguration 的类，您不需要 @EnableTransactionManagement 注释，因为那将是由 Spring Boot 为您启用。 com.spring.app 包中的一个基本应用程序类就足够了。

@Configuration
@EnableAutoConfiguration
@ComponentScan
public class Application {


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

} 

类似的东西应该足以检测到您的所有类(包括实体和基于 Spring Data 的存储库)。

更新:在较新版本的 Spring Boot 中，这些注释可以替换为单个 @SpringBootApplication。

@SpringBootApplication
public class Application {

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

我还建议删除 commons-dbcp 依赖项，因为这将允许 Spring Boot 配置更快、更健壮的 HikariCP实现。