Spring Boot 1.4.1可运行jar javax.persistence.persistenceException：无法解析持久性单位根URL

Question

我们有一个Spring Boot1.4.1应用程序，当我们创建可运行的jar并尝试运行它时，我们会得到以下堆栈跟踪：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'xxxEntityManager' defined in class path resource [xxx/web/config/XxxConfig.class]: Invocation of init method failed; nested exception is javax.persistence.Persistenc
eException: Unable to resolve persistence unit root URL
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1583) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1076) ~[spring-context-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:851) ~[spring-context-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541) ~[spring-context-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.4.1.RELEASE.jar!/:1.4.1.RELEASE]
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:761) [spring-boot-1.4.1.RELEASE.jar!/:1.4.1.RELEASE]
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:371) [spring-boot-1.4.1.RELEASE.jar!/:1.4.1.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-1.4.1.RELEASE.jar!/:1.4.1.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1186) [spring-boot-1.4.1.RELEASE.jar!/:1.4.1.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1175) [spring-boot-1.4.1.RELEASE.jar!/:1.4.1.RELEASE]
        at xxx.App.main(App.java:48) [classes!/:0.0.1-SNAPSHOT]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_05]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_05]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_05]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_05]
        at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48) [NES-Web-0.0.1-SNAPSHOT-exec.jar:0.0.1-SNAPSHOT]
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:87) [NES-Web-0.0.1-SNAPSHOT-exec.jar:0.0.1-SNAPSHOT]
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:50) [NES-Web-0.0.1-SNAPSHOT-exec.jar:0.0.1-SNAPSHOT]
        at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:58) [NES-Web-0.0.1-SNAPSHOT-exec.jar:0.0.1-SNAPSHOT]
Caused by: javax.persistence.PersistenceException: Unable to resolve persistence unit root URL
        at org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager.determineDefaultPersistenceUnitRootUrl(DefaultPersistenceUnitManager.java:605) ~[spring-orm-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager.preparePersistenceUnitInfos(DefaultPersistenceUnitManager.java:445) ~[spring-orm-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager.afterPropertiesSet(DefaultPersistenceUnitManager.java:426) ~[spring-orm-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:325) ~[spring-orm-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:373) ~[spring-orm-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:362) ~[spring-orm-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1642) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1579) ~[spring-beans-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        ... 24 common frames omitted
Caused by: java.io.FileNotFoundException: class path resource [] cannot be resolved to URL because it does not exist
        at org.springframework.core.io.ClassPathResource.getURL(ClassPathResource.java:187) ~[spring-core-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        at org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager.determineDefaultPersistenceUnitRootUrl(DefaultPersistenceUnitManager.java:602) ~[spring-orm-4.3.3.RELEASE.jar!/:4.3.3.RELEASE]
        ... 31 common frames omitted

我们也找到了这个问题https://github.com/spring-projects/spring-boot/issues/6635，但根据它，这个问题应该在Spring Boot 1.4.1中修复

注意：我们的模型类中没有注释，我们使用hbm.xml文件进行映射。但是，我们使用Spring数据JPA存储库。

Answer 1

根据我在这里读到的说明(https://github.com/spring-projects/spring-boot/issues/6983#issuecomment-249981782)，我通过以下操作创建了该问题的解决方案：

>

我创建了meta-inf/orm.xml文件，并将其放在src/main/resources文件夹中。文件的内容可以在以下链接中找到:https://github.com/spring-projects/spring-data-jpa/blob/master/src/test/resources/meta-inf/orm.XML（实际上不需要persistence-unit-metadata、named-query和entity标记，只需要一个带有根entity-mappings标记的空XML就够了）。

在配置LocalContainerEntityManagerFactoryBean bean时，我需要调用setPersistenceUnitRootLocation方法，并将location设置为classpath：meta-inf/orm.xml

这个变通解决了我的问题时运行脂肪罐。但是，通过实现这个解决办法，我产生了另一个问题--我无法从IDE运行一个应用程序，所以我必须基于某种指示符实现持久性单元的根位置的某种条件设置，不管我是从jar还是从IDE运行。