jpa 与spring boot结合,查询数据库 返回的列表中都是同一个实例

public interface RedisStatusDao extends CrudRepository {
public List findByRedisIdOrderByRecoderTimeDesc(Integer redis_id);
}
这是我调用的方法但是在MySQL中写SQL语句,返回结果个数是对的,但是都是正确结果的第1条记录
SELECT * FROM redis_status WHERE redis_id=10 ORDER BY recoder_time DESC
结果很正常。经过调试redis_id这个参数也对,但就是结果内容有问题,请问这是怎么回事?该怎么解决?麻烦大家了

4个回答

可以考虑将返回值记录包装为实体RedisInfo,接口就编程

 public interface RedisStatusDao extends CrudRepository<RedisInfo, ID> {
public List<RedisInfo> findByRedisIdOrderByRecoderTimeDesc(Integer redis_id);
}

后来写了两个小时重新运行一下就好了,可能IDE不稳定吧 多谢夕阳雨晴

也可能是id的值都是一样的。。。我遇到了类似问题

weixin_43554925
yumeart 赞同,我这边就是因为代码中entity设置的id在数据库中的的数据是一样的
大约一年之前 回复

你实例中的@Id 标错位置了

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spring boot + jpa访问数据库时报这个错,调用CrudRepository保存的时候
java.lang.NullPointerException: null at com.yd.cn.controller.SampleController.hello(SampleController.java:26) ~[classes/:na] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_102] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_102] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_102] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_102] at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:817) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:731) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:968) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:859) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:622) ~[servlet-api.jar:na] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:844) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[servlet-api.jar:na] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-websocket.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcAutoConfiguration$ApplicationContextHeaderFilter.doFilterInternal(EndpointWebMvcAutoConfiguration.java:237) ~[spring-boot-actuator-1.3.3.RELEASE.jar:1.3.3.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:112) ~[spring-boot-actuator-1.3.3.RELEASE.jar:1.3.3.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:87) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:103) ~[spring-boot-actuator-1.3.3.RELEASE.jar:1.3.3.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.11] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.11] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[catalina.jar:8.5.11] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:8.5.11] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:474) [catalina.jar:8.5.11] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [catalina.jar:8.5.11] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [catalina.jar:8.5.11] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [catalina.jar:8.5.11] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) [catalina.jar:8.5.11] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783) [tomcat-coyote.jar:8.5.11] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-coyote.jar:8.5.11] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:798) [tomcat-coyote.jar:8.5.11] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1434) [tomcat-coyote.jar:8.5.11] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:8.5.11] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_102] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_102] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:8.5.11] at java.lang.Thread.run(Thread.java:745) [na:1.8.0_102] ![图片说明](https://img-ask.csdn.net/upload/201708/22/1503380371_349769.png)![![图片说明](https://img-ask.csdn.net/upload/201708/22/1503380520_871584.png)图片说明](https://img-ask.csdn.net/upload/201708/22/1503380462_232925.png)
spring boot jpa 动态参数传表名,执行时自动添加单引号
spring boot jpa 动态参数传表名,执行时自动添加单引号怎么办
play-spring-jpa 连接数据库出错
persistence.xml中配置 <persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" version="2.0"> <persistence-unit name="default" transaction-type="JTA"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <jta-data-source>DefaultDS</jta-data-source> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/> <property name="hibernate.hbm2ddl.auto" value="update"/> </properties> </persistence-unit> </persistence> 报错内容 play.api.UnexpectedException: Unexpected exception[UnsatisfiedDependencyExceptio n: Error creating bean with name 'application' defined in file [D:\play-spring-d ata-jpa\target\scala-2.10\classes\controllers\Application.class]: Unsatisfied de pendency expressed through constructor argument with index 0 of type [models.Per sonRepository]: : Error creating bean with name 'personRepository': Cannot creat e inner bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEntityMan agerCreator] while setting bean property 'entityManager'; nested exception is or g.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'entityManagerFactory' w hile setting constructor argument; nested exception is org.springframework.beans .factory.BeanCreationException: Error creating bean with name 'entityManagerFact ory' defined in class Global$SpringDataJpaConfiguration: Instantiation of bean f ailed; nested exception is org.springframework.beans.factory.BeanDefinitionStore Exception: Factory method [public javax.persistence.EntityManagerFactory Global$ SpringDataJpaConfiguration.entityManagerFactory()] threw exception; nested excep tion is javax.persistence.PersistenceException: [PersistenceUnit: default] Unabl e to build EntityManagerFactory; nested exception is org.springframework.beans.f actory.BeanCreationException: Error creating bean with name 'personRepository': Cannot create inner bean '(inner bean)' of type [org.springframework.orm.jpa.Sha redEntityManagerCreator] while setting bean property 'entityManager'; nested exc eption is org.springframework.beans.factory.BeanCreationException: Error creatin g bean with name '(inner bean)#1': Cannot resolve reference to bean 'entityManag erFactory' while setting constructor argument; nested exception is org.springfra mework.beans.factory.BeanCreationException: Error creating bean with name 'entit yManagerFactory' defined in class Global$SpringDataJpaConfiguration: Instantiati on of bean failed; nested exception is org.springframework.beans.factory.BeanDef initionStoreException: Factory method [public javax.persistence.EntityManagerFac tory Global$SpringDataJpaConfiguration.entityManagerFactory()] threw exception; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: de fault] Unable to build EntityManagerFactory] at play.core.ReloadableApplication$$anonfun$get$1$$anonfun$apply$1$$anon fun$1.apply(ApplicationProvider.scala:148) ~[play_2.10.jar:2.2.3] at play.core.ReloadableApplication$$anonfun$get$1$$anonfun$apply$1$$anon fun$1.apply(ApplicationProvider.scala:112) ~[play_2.10.jar:2.2.3] at scala.Option.map(Option.scala:145) ~[scala-library.jar:na] at play.core.ReloadableApplication$$anonfun$get$1$$anonfun$apply$1.apply (ApplicationProvider.scala:112) ~[play_2.10.jar:2.2.3] at play.core.ReloadableApplication$$anonfun$get$1$$anonfun$apply$1.apply (ApplicationProvider.scala:110) ~[play_2.10.jar:2.2.3] at scala.util.Success.flatMap(Try.scala:200) ~[scala-library.jar:na] Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Err or creating bean with name 'application' defined in file [D:\play-spring-data-jp a\target\scala-2.10\classes\controllers\Application.class]: Unsatisfied dependen cy expressed through constructor argument with index 0 of type [models.PersonRep ository]: : Error creating bean with name 'personRepository': Cannot create inne r bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEntityManagerCr eator] while setting bean property 'entityManager'; nested exception is org.spri ngframework.beans.factory.BeanCreationException: Error creating bean with name ' (inner bean)#1': Cannot resolve reference to bean 'entityManagerFactory' while s etting constructor argument; nested exception is org.springframework.beans.facto ry.BeanCreationException: Error creating bean with name 'entityManagerFactory' d efined in class Global$SpringDataJpaConfiguration: Instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanDefinitionStoreExcept ion: Factory method [public javax.persistence.EntityManagerFactory Global$Spring DataJpaConfiguration.entityManagerFactory()] threw exception; nested exception i s javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to b uild EntityManagerFactory; nested exception is org.springframework.beans.factory .BeanCreationException: Error creating bean with name 'personRepository': Cannot create inner bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEnt ityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'entityManagerFact ory' while setting constructor argument; nested exception is org.springframework .beans.factory.BeanCreationException: Error creating bean with name 'entityManag erFactory' defined in class Global$SpringDataJpaConfiguration: Instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanDefinitio nStoreException: Factory method [public javax.persistence.EntityManagerFactory G lobal$SpringDataJpaConfiguration.entityManagerFactory()] threw exception; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory at org.springframework.beans.factory.support.ConstructorResolver.createA rgumentArray(ConstructorResolver.java:730) ~[spring-beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.ConstructorResolver.autowir eConstructor(ConstructorResolver.java:196) ~[spring-beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1045) ~[spri ng-beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:949) ~[spring -beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487) ~[spring-beans .jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans.j ar:3.2.3.RELEASE] Caused by: org.springframework.beans.factory.BeanCreationException: Error creati ng bean with name 'personRepository': Cannot create inner bean '(inner bean)' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bea n property 'entityManager'; nested exception is org.springframework.beans.factor y.BeanCreationException: Error creating bean with name '(inner bean)#1': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argum ent; nested exception is org.springframework.beans.factory.BeanCreationException : Error creating bean with name 'entityManagerFactory' defined in class Global$S pringDataJpaConfiguration: Instantiation of bean failed; nested exception is org .springframework.beans.factory.BeanDefinitionStoreException: Factory method [pub lic javax.persistence.EntityManagerFactory Global$SpringDataJpaConfiguration.ent ityManagerFactory()] threw exception; nested exception is javax.persistence.Pers istenceException: [PersistenceUnit: default] Unable to build EntityManagerFactor y at org.springframework.beans.factory.support.BeanDefinitionValueResolver .resolveInnerBean(BeanDefinitionValueResolver.java:282) ~[spring-beans.jar:3.2.3 .RELEASE] at org.springframework.beans.factory.support.BeanDefinitionValueResolver .resolveValueIfNecessary(BeanDefinitionValueResolver.java:126) ~[spring-beans.ja r:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1387) ~[spri ng-beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.populateBean(AbstractAutowireCapableBeanFactory.java:1128) ~[spring-bean s.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519) ~[spring-beans .jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans.j ar:3.2.3.RELEASE] Caused by: org.springframework.beans.factory.BeanCreationException: Error creati ng bean with name '(inner bean)#1': Cannot resolve reference to bean 'entityMana gerFactory' while setting constructor argument; nested exception is org.springfr amework.beans.factory.BeanCreationException: Error creating bean with name 'enti tyManagerFactory' defined in class Global$SpringDataJpaConfiguration: Instantiat ion of bean failed; nested exception is org.springframework.beans.factory.BeanDe finitionStoreException: Factory method [public javax.persistence.EntityManagerFa ctory Global$SpringDataJpaConfiguration.entityManagerFactory()] threw exception; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: d efault] Unable to build EntityManagerFactory at org.springframework.beans.factory.support.BeanDefinitionValueResolver .resolveReference(BeanDefinitionValueResolver.java:329) ~[spring-beans.jar:3.2.3 .RELEASE] at org.springframework.beans.factory.support.BeanDefinitionValueResolver .resolveValueIfNecessary(BeanDefinitionValueResolver.java:107) ~[spring-beans.ja r:3.2.3.RELEASE] at org.springframework.beans.factory.support.ConstructorResolver.resolve ConstructorArguments(ConstructorResolver.java:615) ~[spring-beans.jar:3.2.3.RELE ASE] at org.springframework.beans.factory.support.ConstructorResolver.instant iateUsingFactoryMethod(ConstructorResolver.java:441) ~[spring-beans.jar:3.2.3.RE LEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:10 25) ~[spring-beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:921) ~[spring -beans.jar:3.2.3.RELEASE] Caused by: org.springframework.beans.factory.BeanCreationException: Error creati ng bean with name 'entityManagerFactory' defined in class Global$SpringDataJpaCo nfiguration: Instantiation of bean failed; nested exception is org.springframewo rk.beans.factory.BeanDefinitionStoreException: Factory method [public javax.pers istence.EntityManagerFactory Global$SpringDataJpaConfiguration.entityManagerFact ory()] threw exception; nested exception is javax.persistence.PersistenceExcepti on: [PersistenceUnit: default] Unable to build EntityManagerFactory at org.springframework.beans.factory.support.ConstructorResolver.instant iateUsingFactoryMethod(ConstructorResolver.java:581) ~[spring-beans.jar:3.2.3.RE LEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:10 25) ~[spring-beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:921) ~[spring -beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487) ~[spring-beans .jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans.j ar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory$1.getOb ject(AbstractBeanFactory.java:295) ~[spring-beans.jar:3.2.3.RELEASE] Caused by: org.springframework.beans.factory.BeanDefinitionStoreException: Facto ry method [public javax.persistence.EntityManagerFactory Global$SpringDataJpaCon figuration.entityManagerFactory()] threw exception; nested exception is javax.pe rsistence.PersistenceException: [PersistenceUnit: default] Unable to build Entit yManagerFactory at org.springframework.beans.factory.support.SimpleInstantiationStrategy .instantiate(SimpleInstantiationStrategy.java:181) ~[spring-beans.jar:3.2.3.RELE ASE] at org.springframework.beans.factory.support.ConstructorResolver.instant iateUsingFactoryMethod(ConstructorResolver.java:570) ~[spring-beans.jar:3.2.3.RE LEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:10 25) ~[spring-beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:921) ~[spring -beans.jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487) ~[spring-beans .jar:3.2.3.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBean Factory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans.j ar:3.2.3.RELEASE] Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Un able to build EntityManagerFactory at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Con figuration.java:915) ~[hibernate-entitymanager-3.6.10.Final.jar:3.6.10.Final] at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(Hib ernatePersistence.java:57) ~[hibernate-entitymanager-3.6.10.Final.jar:3.6.10.Fin al] at javax.persistence.Persistence.createEntityManagerFactory(Persistence. java:63) ~[hibernate-jpa-2.0-api.jar:1.0.1.Final] at javax.persistence.Persistence.createEntityManagerFactory(Persistence. java:47) ~[hibernate-jpa-2.0-api.jar:1.0.1.Final] at Global$SpringDataJpaConfiguration.entityManagerFactory(Global.java:76 ) ~[na:na] at Global$SpringDataJpaConfiguration$$EnhancerByCGLIB$$715a97cd.CGLIB$en tityManagerFactory$0(<generated>) ~[na:na] Caused by: org.hibernate.HibernateException: The chosen transaction strategy req uires access to the JTA TransactionManager at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java: 390) ~[hibernate-core-3.6.10.Final.jar:3.6.10.Final] at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.jav a:1872) ~[hibernate-core-3.6.10.Final.jar:3.6.10.Final] at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Con figuration.java:906) ~[hibernate-entitymanager-3.6.10.Final.jar:3.6.10.Final] at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(Hib ernatePersistence.java:57) ~[hibernate-entitymanager-3.6.10.Final.jar:3.6.10.Fin al] at javax.persistence.Persistence.createEntityManagerFactory(Persistence. java:63) ~[hibernate-jpa-2.0-api.jar:1.0.1.Final] at javax.persistence.Persistence.createEntityManagerFactory(Persistence. java:47) ~[hibernate-jpa-2.0-api.jar:1.0.1.Final]
Spring Data JPA 中的findOne方法如何使用string类型作参数
## 先上图 ![图片说明](https://img-ask.csdn.net/upload/202001/20/1579504915_6319.png) 我在使用SpringBoot 实战这本书学习时,手写其中的案例。 却发现Spring Data JPA中的findOne方法不能接收一个username这个String类型的参数。(ReaderRepository是一个JPA的接口) 求大神指定解决方法。
spring boot 集成activiti如何能在启动时不配置数据库参数
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