Spring Boot 启动时 JDBC 间歇性抽风

报错信息

java.lang.NullPointerException: Cannot invoke "org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(java.sql.SQLException, String)" because the return value of "org.hibernate.resource.transaction.backend.jdbc.internal.JdbcIsolationDelegate.sqlExceptionHelper()" is null
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcIsolationDelegate.delegateWork(JdbcIsolationDelegate.java:116) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.getJdbcEnvironmentUsingJdbcMetadata(JdbcEnvironmentInitiator.java:279) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:193) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:69) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:119) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:264) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:239) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:216) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.boot.model.relational.Database.<init>(Database.java:45) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.getDatabase(InFlightMetadataCollectorImpl.java:231) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.<init>(InFlightMetadataCollectorImpl.java:199) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:169) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:1383) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1454) ~[hibernate-core-6.2.13.Final.jar:6.2.13.Final]
    at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:75) ~[spring-orm-6.0.13.jar:6.0.13]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:376) ~[spring-orm-6.0.13.jar:6.0.13]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:409) ~[spring-orm-6.0.13.jar:6.0.13]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:396) ~[spring-orm-6.0.13.jar:6.0.13]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:352) ~[spring-orm-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1817) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1766) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:598) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:520) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:325) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-6.0.13.jar:6.0.13]
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1166) ~[spring-context-6.0.13.jar:6.0.13]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:940) ~[spring-context-6.0.13.jar:6.0.13]
    ······

报错原因

java.lang.NullPointerException: Cannot invoke "org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(java.sql.SQLException, String)" because the return value of "org.hibernate.resource.transaction.backend.jdbc.internal.JdbcIsolationDelegate.sqlExceptionHelper()" is null是一个典型的 Hibernate 异常，表明在事务处理或数据库交互过程中出现了一个错误，并且 Hibernate 无法正确处理或报告这个错误。

解决方案

通过将以下属性添加到我的 application.properties 文件来解决该问题：

spring.jpa.properties.hibernate.boot.allow_jdbc_metadata_access=false

通过该设置使得 Hibernate 不再尝试在启动期间访问 JDBC 元数据，以避免 Hibernate 在刷新阶段之前联系远程数据库。

注：在 Spring Boot 3.2 / Hibernate 6.4 及更早版本中，使用 spring.jpa.properties.hibernate.temp.use_jdbc_metadata_defaults=false 而不是 spring.jpa.properties.hibernate.boot.allow_jdbc_metadata_access=false。