具有 MySql ManyToMany 关系的 Spring Boot 无法持久保存到数据库，说“java.sql.SQLException：SQL 字符串不能为 NULL”
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【中文标题】具有 MySql ManyToMany 关系的 Spring Boot 无法持久保存到数据库，说“java.sql.SQLException：SQL 字符串不能为 NULL”【英文标题】：Spring Boot with MySql ManyToMany relationship cannot persist to database, says "java.sql.SQLException: SQL String can not be NULL" 【发布时间】：2017-04-06 00:50:56 【问题描述】：所以我在我的项目中使用了 hsqldb，一切正常。然后我将数据库切换到 mysql，问题开始出现。尝试发布新对象时，我在控制台中收到此错误：
Hibernate: null
2016-11-22 12:48:23.959 WARN 9460 --- [nio-8080-exec-1] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Error: 0, SQLState: S1009
2016-11-22 12:48:23.960 ERROR 9460 --- [nio-8080-exec-1] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL String can not be NULL
2016-11-22 12:48:23.995 ERROR 9460 --- [nio-8080-exec-1] 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.orm.jpa.JpaSystemException: could not prepare statement; nested exception is org.hibernate.exception.GenericJDBCException: could not prepare statement] with root cause
java.sql.SQLException: SQL String can not be NULL
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:963) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:896) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:885) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.PreparedStatement.<init>(PreparedStatement.java:819) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.JDBC4PreparedStatement.<init>(JDBC4PreparedStatement.java:45) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.JDBC42PreparedStatement.<init>(JDBC42PreparedStatement.java:39) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_91]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_91]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_91]
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_91]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.PreparedStatement.getInstance(PreparedStatement.java:761) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.clientPrepareStatement(ConnectionImpl.java:1471) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4167) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4071) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_91]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_91]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_91]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_91]
at org.apache.tomcat.jdbc.pool.ProxyConnection.invoke(ProxyConnection.java:126) ~[tomcat-jdbc-8.5.5.jar:na]
at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:108) ~[tomcat-jdbc-8.5.5.jar:na]
at org.apache.tomcat.jdbc.pool.DisposableConnectionFacade.invoke(DisposableConnectionFacade.java:81) ~[tomcat-jdbc-8.5.5.jar:na]
at com.sun.proxy.$Proxy63.prepareStatement(Unknown Source) ~[na:na]
at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$1.doPrepare(StatementPreparerImpl.java:87) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$StatementPreparationTemplate.prepareStatement(StatementPreparerImpl.java:172) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.engine.jdbc.internal.StatementPreparerImpl.prepareStatement(StatementPreparerImpl.java:72) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.id.SequenceGenerator.generateHolder(SequenceGenerator.java:114) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.id.SequenceHiLoGenerator.generate(SequenceHiLoGenerator.java:62) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:101) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.jpa.event.internal.core.JpaPersistEventListener.saveWithGeneratedId(JpaPersistEventListener.java:67) ~[hibernate-entitymanager-5.0.2.Final.jar:5.0.2.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:189) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:132) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:58) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:775) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:748) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:753) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1146) ~[hibernate-entitymanager-5.0.2.Final.jar:5.0.2.Final]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_91]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_91]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_91]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_91]
at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:347) ~[spring-orm-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at com.sun.proxy.$Proxy82.persist(Unknown Source) ~[na:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_91]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_91]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_91]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_91]
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:298) ~[spring-orm-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at com.sun.proxy.$Proxy82.persist(Unknown Source) ~[na:na]
at PersonDao.tryAddUser(PersonDao.java:40) ~[classes/:na]
at eePersonDao$$FastClassBySpringCGLIB$$5a43fcfe.invoke(<generated>) ~[classes/:na]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:720) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136) ~[spring-tx-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at dao.PersonDao$$EnhancerBySpringCGLIB$$a4de6892.tryAddUser(<generated>) ~[classes/:na]
at controller.TestController.addUser(TestController.java:47) ~[classes/:na]
at controller.TestController$$FastClassBySpringCGLIB$$5dbd977d.invoke(<generated>) ~[classes/:na]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:720) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99) ~[spring-tx-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281) ~[spring-tx-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) ~[spring-tx-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655) ~[spring-aop-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at controller.TestController$$EnhancerBySpringCGLIB$$59a5ee5d.addUser(<generated>) ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_91]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_91]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_91]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_91]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:114) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:208) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177) ~[spring-security-web-4.1.3.RELEASE.jar:4.1.3.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:89) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:108) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:784) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:802) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1410) [tomcat-embed-core-8.5.5.jar:8.5.5]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.5.jar:8.5.5]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_91]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_91]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.5.jar:8.5.5]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_91]
2016-11-22 12:52:01.902 DEBUG 9460 --- [nio-8080-exec-2] org.hibernate.SQL : null
Hibernate: null
2016-11-22 12:52:02.032 WARN 9460 --- [nio-8080-exec-2] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Error: 0, SQLState: S1009
2016-11-22 12:52:02.067 ERROR 9460 --- [nio-8080-exec-2] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL String can not be NULL
2016-11-22 12:52:02.441 ERROR 9460 --- [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.orm.jpa.JpaSystemException: could not prepare statement; nested exception is org.hibernate.exception.GenericJDBCException: could not prepare statement] with root cause
我的应用程序.properties
spring.datasource.url = jdbc:mysql://localhost:3306/mydb
spring.datasource.username = user
spring.datasource.password = pass
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
spring.jpa.show-sql = true
我的 Person.class
@Entity
@Table(name="PERSON")
public class Person
@Id
@SequenceGenerator(name = "my_seq", sequenceName = "seq1", allocationSize = 1)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "my_seq")
private long id;
@Column(name = "username", unique=true, nullable = false)
private String username;
private String password;
private Date expirationdate;
private String comment;
@ManyToMany
@JoinTable(name = "USER_RIGHTS", joinColumns = @JoinColumn(name = "username"), inverseJoinColumns = @JoinColumn(name = "name"))
private List<Rights> rights = new ArrayList<>();
public Person()
Getters/setter below...
My Rights.class
@Entity
public class Rights
@Id
@SequenceGenerator(name = "my_seq", sequenceName = "seq1", allocationSize = 1)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "my_seq")
private long id;
private String name;
private String hash;
private String rightsdate;
private long algorithmno;
private String comment;
@ManyToMany(mappedBy = "rights")
private List<Person> persons = new ArrayList<>();
public Rights()
getters/setters below..
测试控制器
@Transactional
@RequestMapping(method = RequestMethod.GET, value = "/user")
public String addUser()
Person p1 = new Person();
p1.setUsername("User1");
p1.setPassword("Pass1");
p1.setComment("1");
p.tryAddUser(p1);
return "User added";
人道
@PersistenceContext
private EntityManager em;
public boolean tryAddUser(Person person)
try
em.persist(person);
return true;
catch (NullPointerException e)
System.out.println("Could not add user " + person);
return false;
邮递员
"timestamp": 1479811922606,
"status": 500,
"error": "Internal Server Error",
"exception": "org.springframework.orm.jpa.JpaSystemException",
"message": "could not prepare statement; nested exception is org.hibernate.exception.GenericJDBCException: could not prepare statement",
"path": "/test/user"
Pom 依赖项（自从开始尝试一切以使其正常工作以来，我知道的太多了）
<dependencies>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-mail</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.10</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.hsqldb</groupId>
<artifactId>hsqldb</artifactId>
<version>2.3.3</version>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt</artifactId>
<version>$jjwt.version</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>5.0.2.Final</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-dbcp</artifactId>
<version>7.0.47</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.2.4.Final</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.8.0</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>$spring.version</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
配置类
@Configuration
@EnableAutoConfiguration
@ComponentScan
public class Application
public static void main(String[] args)
ApplicationContext ctx = SpringApplication.run(Application.class, args);
当尝试持久化任何其他没有 manytomany 的对象时，它工作得很好。
可能是什么问题
【问题讨论】：
也添加配置类 添加配置类 您是否尝试过实体@Id @GeneratedValue(strategy=GenerationType.IDENTITY) 每个实体的身份并在此处查看 您是否尝试过实体@Id @GeneratedValue(strategy=GenerationType.IDENTITY) 每个实体的身份，并在此处查看***.com/questions/26881739/… 试过 @Id @GeneratedValue(strategy=GenerationType.IDENTITY) ;然后它说没有设置ID。之后它尝试将 id 提供给 person，但随后它说“org.hibernate.PersistentObjectException：分离的实体传递给持久化：” 【参考方案1】：所以我只是让它沉没一天，然后做一些其他的事情。今天头脑清楚的把GeneratedValue改为：
@Id
@SequenceGenerator(name = "my_seq", sequenceName = "seq1", allocationSize = 1)
@GeneratedValue(strategy = GenerationType.IDENTITY*, generator = "my_seq")
然后由于某种我不知道的原因它起作用了！昨天它做了“org.hibernate.PersistentObjectException：分离的实体传递给坚持：”
当我尝试同样的事情时。
所以现在一切都解决了。所以Hibernate不支持strategy = GenerationType.SEQUENCE。
【讨论】：
【参考方案2】：我通过从类中删除 @SequenceGenerator 注释解决了这个问题
和@GenericGenerator，@GeneratedValue 来自id。
还将@GeneratedValue(strategy = GenerationType.AUTO) 添加到id。
【讨论】：
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