此qustion与分开： Spring doesn't save object to MongoDB correctly
我SampleClass有一个字段 - TreeMap<String, TreeMap<String,String>> map。当我部署应用程序并运行以下代码时：
SampleClass sample = new SampleClass();
mongo.save(sample, "SampleCollection"); //MongoOperations object
我得到以下例外：
Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.ArrayIndexOutOfBoundsException: 0] with root cause
java.lang.ArrayIndexOutOfBoundsException: 0
at org.springframework.data.util.ParameterizedTypeInformation.getComponentType(ParameterizedTypeInformation.java:147)
at org.springframework.data.util.TypeDiscoverer.getActualType(TypeDiscoverer.java:292)
at org.springframework.data.util.ParentTypeAwareTypeInformation.getActualType(ParentTypeAwareTypeInformation.java:29)
at org.springframework.data.mapping.model.AbstractPersistentProperty.getPersistentEntityType(AbstractPersistentProperty.java:125)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.createAndRegisterProperty(AbstractMappingContext.java:469)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.doWith(AbstractMappingContext.java:427)
at org.springframework.util.ReflectionUtils.doWithFields(ReflectionUtils.java:607)
at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:295)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.createAndRegisterProperty(AbstractMappingContext.java:470)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.doWith(AbstractMappingContext.java:427)
at org.springframework.util.ReflectionUtils.doWithFields(ReflectionUtils.java:607)
at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:295)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.createAndRegisterProperty(AbstractMappingContext.java:470)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.doWith(AbstractMappingContext.java:427)
at org.springframework.util.ReflectionUtils.doWithFields(ReflectionUtils.java:607)
at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:295)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.createAndRegisterProperty(AbstractMappingContext.java:470)
at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.doWith(AbstractMappingContext.java:427)
at org.springframework.util.ReflectionUtils.doWithFields(ReflectionUtils.java:607)
at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:295)
at org.springframework.data.mapping.context.AbstractMappingContext.getPersistentEntity(AbstractMappingContext.java:181)
at org.springframework.data.mapping.context.AbstractMappingContext.getPersistentEntity(AbstractMappingContext.java:141)
at org.springframework.data.mapping.context.AbstractMappingContext.getPersistentEntity(AbstractMappingContext.java:67)
at org.springframework.data.mongodb.core.MongoTemplate.getPersistentEntity(MongoTemplate.java:1831)
at org.springframework.data.mongodb.core.MongoTemplate.save(MongoTemplate.java:829)
at com.sample.MongoTest.saveToMongo(MongoTest.java:22)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
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:620)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:683)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1720)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1679)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
此异常仅在部署后抛出一次。我发现当我用TreeMap<String, String>替换字段时它工作正常，没有异常可以观察到。
通常情况下，我认为MongoDB在处理地图地图时遇到了问题（这种情况是treeMaps的treeMap），但事实并非如此。
最大的问题是它有效。我的代码是更大模块的一部分，几天前它已迁移到单独的项目中。当它是模块的一部分时，它工作正常，但现在当它是分离的项目时，它不想工作。
提问时间
我用不同的Mongo后端测试了这段代码，它的行为相同，所以mongo实例没有问题。
修改
当我第二次运行应用程序时（部署后没有发生异常时），它会正确保存数据。但是由于Exception，我不能确定它是否能在生产中正常工作。