mybatis和jpa都是需要实体操作数据库的吗？

现在需要写个系统，但是公司要求用存储过程，直接拿参数请求存储过程 hibernate可以实现 mybatis和jpa可以吗？ 还有一个问题是，数据库表正在使用，直接添加表的字段会不会对程序造成影响？

Spring boot + Spring Data JPA + Hibernate缓存问题

如题，项目框架为Spring boot + Spring Data JPA + Hibernate，hibernate中有Query.list()和query.iterator()方法，其中query.iterator()方法去查询时会用到缓存，返回的参数类型是Iterator,如果使用Spring Data JPA+hibernate如何实现查询一个list使用到缓存呢，JPA中的PagingAndSortingRepository接口中的findAll()方法返回的Iterator类型好像和query.iterator()的效果不一样，哪个哥们可以解答下，万分感激！

spring boot jpa 多表联查

spring boot JPA 中多表联查怎么搞？关联查A表和B表中的字段，怎么返回结果集？

Spring Boot 使用JPA连接MySQL数据库报错 is not mapped

小白向各位大侠求助： 创建Spring Boot 工程时，使用JPA连接MySQL数据库，查询时报错，报错信息如下： ``` 2018-06-04 06:34:44.959 ERROR 6116 --- [nio-8080-exec-2] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.dao.InvalidDataAccessApiUsageException: org.hibernate.hql.internal.ast.QuerySyntaxException: Person is not mapped [select t from Person t]; nested exception is java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: Person is not mapped [select t from Person t]] with root cause org.hibernate.hql.internal.ast.QuerySyntaxException: Person is not mapped at org.hibernate.hql.internal.ast.util.SessionFactoryHelper.requireClassPersister(SessionFactoryHelper.java:169) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.ast.tree.FromElementFactory.addFromElement(FromElementFactory.java:91) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.ast.tree.FromClause.addFromElement(FromClause.java:79) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.ast.HqlSqlWalker.createFromElement(HqlSqlWalker.java:326) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElement(HqlSqlBaseWalker.java:3706) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElementList(HqlSqlBaseWalker.java:3595) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromClause(HqlSqlBaseWalker.java:720) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:576) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:313) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:261) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:266) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:189) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:141) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:115) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:77) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:153) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan(AbstractSharedSessionContract.java:553) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:662) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at org.hibernate.internal.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:23) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_131] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_131] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_131] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_131] at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:350) ~[spring-orm-5.0.6.RELEASE.jar:5.0.6.RELEASE] at com.sun.proxy.$Proxy76.createQuery(Unknown Source) ~[na:na] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_131] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_131] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_131] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_131] at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:304) ~[spring-orm-5.0.6.RELEASE.jar:5.0.6.RELEASE] at com.sun.proxy.$Proxy76.createQuery(Unknown Source) ~[na:na] at com.neuqsoft.demo.repository.impl.PersonDaoImpl.findAll(PersonDaoImpl.java:52) ~[classes/:na] at com.neuqsoft.demo.repository.impl.PersonDaoImpl$$FastClassBySpringCGLIB$$7895840c.invoke(<generated>) ~[classes/:na] at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) ~[spring-core-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:746) ~[spring-aop-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688) ~[spring-aop-5.0.6.RELEASE.jar:5.0.6.RELEASE] at com.neuqsoft.demo.repository.impl.PersonDaoImpl$$EnhancerBySpringCGLIB$$182f86eb.findAll(<generated>) ~[classes/:na] at com.neuqsoft.demo.service.PersonService.findAll(PersonService.java:50) ~[classes/:na] at com.neuqsoft.demo.controller.PersonController.getPseronList(PersonController.java:59) ~[classes/:na] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_131] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_131] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_131] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_131] at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851) ~[spring-webmvc-5.0.6.RELEASE.jar:5.0.6.RELEASE] at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.6.RELEASE.jar:5.0.6.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468) [tomcat-embed-core-8.5.31.jar:8.5.31] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.31.jar:8.5.31] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_131] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_131] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.31.jar:8.5.31] at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131] ``` 实体文件： ``` @Entity @Table(name = "person") public class Person { @Id @GeneratedValue(strategy = GenerationType.AUTO) private String id; @Column(name="name") private String name; @Column(name="sex") private String sex; @Column(name="tel") private String tel; @Column(name="address") private String address; @Column(name="age") private String age; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public String getTel() { return tel; } public void setTel(String tel) { this.tel = tel; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public String getAge() { return age; } public void setAge(String age) { this.age = age; } } ``` 数据库表：  DAO文件： ``` package com.neuqsoft.demo.repository.impl; import java.util.List; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Repository; import com.neuqsoft.demo.entity.Person; import com.neuqsoft.demo.repository.PersonDao; @Repository public class PersonDaoImpl implements PersonDao { @Autowired @PersistenceContext private EntityManager entityManager; @Override public List<Person> findAll() { return this.entityManager.createQuery("select t from Person t").getResultList(); } } ``` Pom.xml ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.neuqsoft</groupId> <artifactId>DemoJPAForSpringBoot</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>war</packaging> <name>DemoJPAForSpringBoot</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.2.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!-- custom renw --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.0</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ``` application.properties： ``` #mysql #datasource spring.datasource.driver-class-name=com.mysql.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost:3306/forspringboot?useSSL=false spring.datasource.username=root spring.datasource.password=1qaz!QAZ spring.jpa.show-sql= true ```

Spring Data jpa+Mongodb查询全部数据出错

代码： List<Comment> comments = commentDao.findAll(); findAll为继承自MongoRepository的方法 报错： Caused by: com.mongodb.MongoQueryException: Query failed with error code 2 and error message 'Field 'locale' is invalid in: { locale: "comment" }' on server localhost:27017 at com.mongodb.operation.FindOperation$1.call(FindOperation.java:735) at com.mongodb.operation.FindOperation$1.call(FindOperation.java:725) at com.mongodb.operation.OperationHelper.withReadConnectionSource(OperationHelper.java:463) at com.mongodb.operation.FindOperation.execute(FindOperation.java:725) at com.mongodb.operation.FindOperation.execute(FindOperation.java:89) at com.mongodb.client.internal.MongoClientDelegate$DelegateOperationExecutor.execute(MongoClientDelegate.java:189) at com.mongodb.client.internal.MongoIterableImpl.execute(MongoIterableImpl.java:143) at com.mongodb.client.internal.MongoIterableImpl.iterator(MongoIterableImpl.java:92) at org.springframework.data.mongodb.core.MongoTemplate.executeFindMultiInternal(MongoTemplate.java:2793) ... 86 more 试过换工程、换数据库、换表、换版本，依旧没有解决，而且几乎搜不到这个错误。

spring data jpa 拦截

spring boot项目，数据层spring data jpa 现在想在数据层把个人信息的敏感字段加密？因为项目过大，如何事项在查询语句执行之前增加拦截，将查询参数进行加密，及获取数据后将查询数据进行解密。

Spring Boot Jpa 多表关联查询问题

jpa单表分页查询很简单一个自带的findall方法就搞定。那么类似下面的多表关联分页查询该如何解决呢？ SELECT t.id,t.co_name,e.experiment_code,e.experiment_name FROM tb_component t, tb_component_flow tf, tb_experiment_apply e WHERE t.id = tf.component_id AND tf.experiment_apply_id = e.id AND e.experiment_name LIKE '%实验%' _***跪求大佬们在线指点。**

spring data jpa 第一行代码我save了某一个表的数据，看到数据库数据变了。

spring data jpa 第一行代码我save了某一个表的数据，看到数据库数据变了。 我第二行去查询这个表的数据，得到的却是没保存数据之前的数据。 再刷新页面就得到了现在数据库的数据是咋回事呢

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/201708/22/1503380462_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

spring boot 集成activiti如何能在启动时不配置数据库参数

<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>leave</artifactId> <version>0.0.1-SNAPSHOT</version> <name>leave</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.activiti</groupId> <artifactId>activiti-spring-boot-starter-basic</artifactId> <version>6.0.0</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web-services</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ------上面是spring boot 的pom.xml 在application.properties配置好数据库参数就可以正常运行。我的想法是在程序启动的时候不连接数据库，在程序运行的过程中按需连接到数据库，但我删除了数据可参数的时候就报错了！！！信息如下： Description: Cannot determine embedded database driver class for database type NONE Action: If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active). 在网上找到的解决方案是添加注解(分别如下尝试都出错)： 1.------------------------- @EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class,HibernateJpaAutoConfiguration.class}) @SpringBootApplication 2.--------------------------------------- @SpringBootApplication(exclude={DataSourceAutoConfiguration.class}) 3.------------------------------------ @SpringBootApplication(exclude = {DataSourceAutoConfiguration.class,DataSourceTransactionManagerAutoConfiguration.class,HibernateJpaAutoConfiguration.class}) 错误信息如下： Description: Parameter 0 of method springProcessEngineConfiguration in org.activiti.spring.boot.JpaProcessEngineAutoConfiguration$JpaConfiguration required a bean of type 'javax.sql.DataSource' that could not be found. - Bean method 'dataSource' not loaded because @ConditionalOnProperty (spring.datasource.jndi-name) did not find property 'jndi-name' - Bean method 'dataSource' not loaded because @ConditionalOnBean (types: org.springframework.boot.jta.XADataSourceWrapper; SearchStrategy: all) did not find any beans Action: Consider revisiting the conditions above or defining a bean of type 'javax.sql.DataSource' in your configuration

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]

jpa通过连接池连接数据库 怎样算是一次连接

在使用jpa操作mysql数据库时 <br> jpa通过连接池连接数据库 怎样算是一次连接？ 连接什么时候结束？

Jpa查询数据库操作，希望各位大牛看看帮帮忙。

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