目录

• JPA出现错误Noidentifierspecifiedforen
• 问题描述
• 问题原因
• 解决方案
• Noidentifierspecifiedforentity:XXXX错误
• 原因及其解决

JPA出现错误No identifier specified for en
问题描述
启动项目未成功，报错如下：

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-03-17 13:19:24.391|main|ERROR|org.springframework.boot.SpringApplication.reportFailure:858|Application run failed
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 org.hibernate.AnnotationException: No identifier specified for entity: com.xxx.domain.Earnings
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1745)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:576)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:498)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1083)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:853)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:546)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:316)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248)
at com.xxx.YoufanApplication.main(YoufanApplication.java:21)
Caused by: org.hibernate.AnnotationException: No identifier specified for entity: com.xxx.domain.Earnings
at org.hibernate.cfg.InheritanceState.determineDefaultAccessType(InheritanceState.java:266)
at org.hibernate.cfg.InheritanceState.getElementsToProcess(InheritanceState.java:211)
at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:778)
at org.hibernate.boot.model.source.internal.annotations.AnnotationMetadataSourceProcessorImpl.processEntityHierarchies(AnnotationMetadataSourceProcessorImpl.java:250)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess$1.processEntityHierarchies(MetadataBuildingProcess.java:231)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:274)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:904)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:935)
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:57)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:390)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:377)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1804)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1741)
... 16 common frames omitted
Disconnected from the target VM, address: '127.0.0.1:50341', transport: 'socket'
Process finished with exit code 1

首先从其中找到核心错误描述：

Invocation of init method failed; nested exception is org.hibernate.AnnotationException: No identifier specified for entity: com.xxx.domain.Earnings

问题原因
在实体类com.xxx.domain.Earnings使用javax.persistence.Entity进行注解就会自动进行表的DDL操作
使用hibernate的映射表的时候entity类是必须要主键的，否则就会报出这个异常：No identifier specified for entity

解决方案

import javax.persistence.*; @Entitypublic class Earnings {@Id@GeneratedValue(strategy = GenerationType.AUTO)Long id; // ...}

【SpringBoot|SpringBoot JPA出现错误:No identifier specified for en解决方案】使用@javax.persistence.Id进行注解后，问题解决。

No identifier specified for entity: XXXX错误 在运行项目的时候报了下面的错误：

by: org.hibernate.AnnotationException: No identifier specified for entity: com.example1.demo1.Entity.User
at org.hibernate.cfg.InheritanceState.determineDefaultAccessType(InheritanceState.java:266) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.cfg.InheritanceState.getElementsToProcess(InheritanceState.java:211) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:731) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.boot.model.source.internal.annotations.AnnotationMetadataSourceProcessorImpl.processEntityHierarchies(AnnotationMetadataSourceProcessorImpl.java:249) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess$1.processEntityHierarchies(MetadataBuildingProcess.java:222) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:265) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:861) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:888) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]

原因及其解决
这是因为在实体的getID方法上没有加上此@Id注解，但是检查了一次确实加上了，最后的解决办法如下：
1.在数据库表对应实体（entity.java）的方法:getId()前加上该段文字注解

@Id@GeneratedValue(strategy= GenerationType.AUTO)

2.是因为id注解引错了包
错误的包路径：

import org.springframework.data.annotation.Id;

正确的包路径：

import javax.persistence.Id;

以上为个人经验，希望能给大家一个参考，也希望大家多多支持脚本之家。

推荐阅读

• 

  三星手机s6的返回键灯怎么开 三星s6edge返回键不亮怎么办
• 

  叛逆啊，少年！（张鹏老师《解码青春期》读书笔记）
• 

  行程码带星号还能出门吗
• 

  抗疫死亡英雄名单 抗疫烈士名单
• 

  脚印怎么画 脚印简笔画教程
• 

  Python+树莓派制作IoT（物联网）门控设备
• 

  东西热的可以放冰箱吗 东西热的能放冰箱吗?
• 

  踏板摩托车风门在哪
• 

  mysql怎么修改数据库名称 mysql数据库中怎么修改数据表名
• 

  cdr符号怎么还原对象
• 

  0x000007b蓝屏修复方法
• 

  快吧游戏盒将开启自动运行关掉具体操作流程
• 

  无货源开店骗局 重庆做电商有什么合适做的货源，无货源电商
• 

  猪蹄炖什么食材好吃呢
• 

  仅因邻居大妈一句戏话，毁掉了一个二胎家庭，很值得深思......
• 

  边旅行，边音乐—音乐旅行
• 

  顽固血渍怎么去除
• 

  大学生用口红一般什么价位,有什么好推荐的吗？
• 

  描写祖国风光的句子诗句 描写祖国风光的句子
• 

  抖音天天摔轮胎的人是谁？抖音天天摔轮胎是什么梗

• 关于@Query注解的用法(Spring|关于@Query注解的用法(Spring Data JPA)
• springboot----二、Hello|springboot----二、Hello,SpringBoot！
• java|微信上传 wx.chooseMedia和wx.uploadFile使用，java springboot后端跑通
• SpringBoot|SpringBoot 入门（环境搭建与HelloWorld~）
• springboot如何获取yml里面的属性值
• 一篇文章带你了解Java|一篇文章带你了解Java SpringBoot Nacos
• 基于Java+SpringBoot+vue+element实现扶贫助农政策平台系统
• SpringBoot|SpringBoot 搭建基于 MinIO 的高性能存储服务
• 在SpringBoot项目中实现给所有请求加固定前缀
• springboot如何读取自定义属性