Question

我需要获取我的架构中存在的所有表的动态信息 ，元信息包括表，实体，列名等。

我遵循了以下教程

https://vladmihalcea.com/how-to-get-the-entity-mapping-to-database-table-binding-metadata-from-hibernate/

如上面的链接所述，我创建了一个名为MetadataExtractorIntegrator.java的集成器。

jpa:
  properties:
    hibernate.integrator_provider: com.test.ttv.MetadataExtractorIntegrator

并尝试通过以下配置在我的应用程序中注册

application.yml

Caused by: java.lang.ClassCastException: java.lang.String cannot be cast to org.hibernate.jpa.boot.spi.IntegratorProvider

开始构建时出现以下异常

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is java.lang.ClassCastException: java.lang.String cannot be cast to org.hibernate.jpa.boot.spi.IntegratorProvider
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1710) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:583) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:502) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:312) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:310) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1085) ~[spring-context-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:858) ~[spring-context-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:388) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1246) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1234) [spring-boot-2.0.0.RELEASE.jar:2.0.0.RELEASE]
        at testtest(Test.java:31) [main/:na]
Caused by: java.lang.ClassCastException: java.lang.String cannot be cast to org.hibernate.jpa.boot.spi.IntegratorProvider
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.buildBootstrapServiceRegistry(EntityManagerFactoryBuilderImpl.java:339) ~[hibernate-core-5.2.14.Final.jar:5.2.14.Final]
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.<init>(EntityManagerFactoryBuilderImpl.java:196) ~[hibernate-core-5.2.14.Final.jar:5.2.14.Final]
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.<init>(EntityManagerFactoryBuilderImpl.java:164) ~[hibernate-core-5.2.14.Final.jar:5.2.14.Final]
        at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:51) ~[spring-orm-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:388) ~[spring-orm-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:377) ~[spring-orm-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341) ~[spring-orm-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1769) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1706) ~[spring-beans-5.0.4.RELEASE.jar:5.0.4.RELEASE]
        ... 16 common frames omitted

更多StackTrace

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有人可以帮我解决这个问题吗？谢谢

Answer 1

在Spring Boot中，spring.jpa.properties指向Map<String, String>，因此它只能包含String值。

但是在Hibernate中，当EntityManagerFactoryBuilderImpl读到hibernate.integrator_provider时，它期望找到IntegratorProvider的实例而不是类名，因此是一个例外。

不过，您可以添加实现HibernatePropertiesCustomizer的bean，以将IntegrationProvider实例添加到Hibernate属性中：

@Component
public class HibernateConfig implements HibernatePropertiesCustomizer {

    @Override
    public void customize(Map<String, Object> hibernateProperties) {
        hibernateProperties.put("hibernate.integrator_provider",
                (IntegratorProvider) () -> Collections.singletonList(MetadataExtractorIntegrator.INSTANCE));
    }
}

我在this repository中创建了一个工作示例。

Answer 2

如果您使用的是Springboot 1.5.x，则“ HibernatePropertiesCustomizer”不存在。

我从here找到了可用的解决方案。您不能在此处使用积分器，但是可以一个一个地添加所有事件侦听器。下面是我的代码：

public class RootAwareInsertEventListener implements PersistEventListener {

    public static final RootAwareInsertEventListener INSTANCE = new RootAwareInsertEventListener();

    @Override
    public void onPersist(PersistEvent event) throws HibernateException {
        final Object entity = event.getObject();

        if (entity instanceof RootAware) {
            RootAware rootAware = (RootAware) entity;
            Object root = rootAware.getRoot();
            event.getSession().lock(root, LockMode.OPTIMISTIC_FORCE_INCREMENT);

            log.info("Incrementing {} entity version because a {} child entity has been inserted",
                    root, entity);
        }
    }

    @Override
    public void onPersist(PersistEvent event, Map createdAlready)
            throws HibernateException {
        onPersist(event);
    }
}

@Component
public class HibernateListenerConfigurer {

    @PersistenceUnit
    private EntityManagerFactory emf;

    @PostConstruct
    protected void init() {
        SessionFactoryImpl sessionFactory = emf.unwrap(SessionFactoryImpl.class);
        EventListenerRegistry registry = sessionFactory.getServiceRegistry().getService(EventListenerRegistry.class);
        registry.getEventListenerGroup(EventType.PERSIST).appendListener(RootAwareInsertEventListener.INSTANCE);
        registry.getEventListenerGroup(EventType.FLUSH_ENTITY).appendListener(RootAwareUpdateAndDeleteEventListener.INSTANCE);

    }
}

Answer 3

在org.springframework.orm.hibernate5.LocalSessionFactoryBean中，有一个hibernateIntegrators的可变参数设置方法，该方法将接受org.hibernate.integrator.spi.Integrator的一个或多个实例

因此，在org.springframework.orm.hibernate5.LocalSessionFactoryBean配置中，添加以下属性

<property name="hibernateIntegrators" ref="metadataExtractorIntegrator" />

并将Integrator设置为托管bean

    package com.test.ttv;
    import org.hibernate.boot.Metadata;
    import org.hibernate.boot.model.relational.Database;
    import org.hibernate.engine.spi.SessionFactoryImplementor;
    import org.hibernate.service.spi.SessionFactoryServiceRegistry;
    import org.springframework.stereotype.Component;

    @Component  
    public class MetadataExtractorIntegrator implements org.hibernate.integrator.spi.Integrator {

        private Database database;

        private Metadata metadata;

        public Database getDatabase() {
            return database;
        }

        public Metadata getMetadata() {
            return metadata;
        }

        @Override
        public void integrate(
                Metadata metadata,
                SessionFactoryImplementor sessionFactory,
                SessionFactoryServiceRegistry serviceRegistry) {

            this.database = metadata.getDatabase();
            this.metadata = metadata;

        }

        @Override
        public void disintegrate(
            SessionFactoryImplementor sessionFactory,
            SessionFactoryServiceRegistry serviceRegistry) {

        }
    }

如何在Spring Boot-JPA-Hibernate中获取所有表元数据？

3 个答案: