当我有以下实体时-
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "question", nullable = false, referencedColumnName="id")
我得到以下错误。但是，在仅将@ManyToOne关联作为EAGER之后，将双向@OneToMany保留为LAZY后，该错误消失了。
如何通过带有Spring DATA REST的LAZY @ManyToOne使其工作
java.lang.IllegalArgumentException: Id must be assignable to Serializable! Object of class [null] must be an instance of interface java.io.Serializable
at org.springframework.util.Assert.isInstanceOf(Assert.java:339)
at org.springframework.data.rest.webmvc.support.RepositoryEntityLinks.linkToSingleResource(RepositoryEntityLinks.java:160)
at org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler.getSelfLinkFor(PersistentEntityResourceAssembler.java:203)
at org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler.wrap(PersistentEntityResourceAssembler.java:107)
at org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler.toResource(PersistentEntityResourceAssembler.java:84)
at org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController$1.apply(RepositoryPropertyReferenceController.java:141)
at org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController$1.apply(RepositoryPropertyReferenceController.java:110)
at org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.doWithReferencedProperty(RepositoryPropertyReferenceController.java:464)
at org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.followPropertyReference(RepositoryPropertyReferenceController.java:148)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:769)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1125)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1059)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
at org.eclipse.jetty.server.Server.handle(Server.java:497)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:248)
at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:610)
at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:539)
at java.lang.Thread.run(Thread.java:745)
URL错误：/ api / users / 2 / question
{
"cause" : null,
"message" : "Id must be assignable to Serializable! Object of class [null] must be an instance of interface java.io.Serializable"
}
最佳答案
现在，该问题似乎已在1.8 M1版本中解决。
如JIRA中所述，
“请务必添加以将Jackson Hibernate 4模块添加到
让杰克逊适当地代理。”
关于java - ID必须可分配给Serialize With With LAZY @ManyToOne，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/26322985/