启动项目报Error creating bean with name 'entityManagerFactory' defined in URL

SSH项目，平常是可以正常启动运行的。

昨天什么都没有动，今天启动项目就报了如下错误：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in URL [file:/E:/ExecutingSoftwareSpace/WorkingSoftwareSpace/apache-tomcat-7.0.91-windows-x64/apache-tomcat-7.0.91/webapps/web/WEB-INF/classes/applicationContext.xml]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1514)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:293)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:290)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:191)
	at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1123)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:928)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
	at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:410)
	at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
	at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112)
	at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5157)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5680)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1707)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1697)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:745)
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory
	at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:925)
	at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:900)
	at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:76)
	at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:290)
	at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:310)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1573)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1511)
	... 21 more
Caused by: org.hibernate.AnnotationException: No identifier specified for entity: com.transinfo.secondDevelop.entity.CarAmout1Part1
	at org.hibernate.cfg.InheritanceState.determineDefaultAccessType(InheritanceState.java:277)
	at org.hibernate.cfg.InheritanceState.getElementsToProcess(InheritanceState.java:224)
	at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:707)
	at org.hibernate.cfg.Configuration$MetadataSourceQueue.processAnnotatedClassesQueue(Configuration.java:3625)
	at org.hibernate.cfg.Configuration$MetadataSourceQueue.processMetadata(Configuration.java:3579)
	at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1381)
	at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1786)
	at org.hibernate.ejb.EntityManagerFactoryImpl.(EntityManagerFactoryImpl.java:96)
	at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:915)
	... 27 more
十月 15, 2019 8:56:54 上午 org.apache.catalina.core.StandardContext listenerStart
严重: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in URL [file:/E:/ExecutingSoftwareSpace/WorkingSoftwareSpace/apache-tomcat-7.0.91-windows-x64/apache-tomcat-7.0.91/webapps/web/WEB-INF/classes/applicationContext.xml]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1514)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:293)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:290)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:191)
	at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1123)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:928)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
	at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:410)
	at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
	at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112)
	at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5157)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5680)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1707)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1697)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:745)
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory
	at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:925)
	at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:900)
	at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:76)
	at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:290)
	at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:310)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1573)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1511)
	... 21 more
Caused by: org.hibernate.AnnotationException: No identifier specified for entity: com.transinfo.secondDevelop.entity.CarAmout1Part1
	at org.hibernate.cfg.InheritanceState.determineDefaultAccessType(InheritanceState.java:277)
	at org.hibernate.cfg.InheritanceState.getElementsToProcess(InheritanceState.java:224)
	at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:707)
	at org.hibernate.cfg.Configuration$MetadataSourceQueue.processAnnotatedClassesQueue(Configuration.java:3625)
	at org.hibernate.cfg.Configuration$MetadataSourceQueue.processMetadata(Configuration.java:3579)
	at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1381)
	at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1786)
	at org.hibernate.ejb.EntityManagerFactoryImpl.(EntityManagerFactoryImpl.java:96)
	at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:915)
	... 27 more

为了看着方便，就摘其中的几个要点：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in URL [file:/E:/ExecutingSoftwareSpace/WorkingSoftwareSpace/apache-tomcat-7.0.91-windows-x64/apache-tomcat-7.0.91/webapps/web/WEB-INF/classes/applicationContext.xml]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory……
 
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory……
  
Caused by: org.hibernate.AnnotationException: No identifier specified for entity: com.transinfo.secondDevelop.entity.CarAmout1Part1……

Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory……
    
Caused by: org.hibernate.AnnotationException: No identifier specified for entity: com.transinfo.secondDevelop.entity.CarAmout1Part1……

通过分析可以知道是数据（连接数据库的问题），但一直以为是编译、数据库配置和连接上的问题，一直盯着entityManagerFactory。但是后来一番折腾之后，真正的问题是：

No identifier specified for entity

意思就是实体类里没有主键（因为数据库表没有id一值，我也没用上），后来去检查，实体类确实没有主键。

最开始的实体类代码是这样的：

@Entity
@Table(name="XXXXXX")
public class CarAmout1Part1{ // extends BaseEntity
	
	
	@Column(name = "D7", length = 100)
	private String d7; 
	
	@Column(name = "D8", length = 100)
	private String d8;
	
	@Column(name="USERID_", length = 100)
	private String userId_;
	
	@Column(name="BTYPE_", length = 100)
	private String btype_; 
	
	@Column(name="BBQ_",length=20)
	private String bbq_;

	//后面的get和set方法就不放进来了

}

后来在userId_（数据库表中并没有将它单独设为主键），加上@Id 即可正常启动，至于之前为什么没有这个东西也能启动，我也搞不清楚了。

贴一下代码：

@Entity
@Table(name="XXXXXX")
public class CarAmout1Part1{ // extends BaseEntity
	
	
	@Column(name = "D7", length = 100)
	private String d7;
	
	@Column(name = "D8", length = 100)
	private String d8;
	
	@Id
	@Column(name="USERID_", length = 100)
	private String userId_; 
	
	@Column(name="BTYPE_", length = 100)
	private String btype_; 
	
	@Column(name="BBQ_",length=20)
	private String bbq_;
	
	//同样，略去get和set方法

}

重新启动，问题得以解决。

仅以此笔记记录一下，方便帮助后面遇到同样bug的朋友。