bean类的属性'fields[0]'无效

我正在和 Spring 天一起工作，我的实体是

myEntity.java

@Entity
public class Ecran {
...
@OneToMany(fetch=FetchType.EAGER, cascade = { CascadeType.ALL } , mappedBy="ecran")
public Set<Fields> fields = new HashSet<>();

...
}

而我正在尝试更改这样的字段的属性

myPage.html

<div th:each="field, itemStat : *{fields}" >

                <div class="row table-responsive-xl mt-3" >
                    <label class="font-weight-medium h5 black-text"  th:text="${field.nom}" for="${field.idJira}"></label>
                    <input type="text" id="${field.id}" class="form-control mb-6" th:field="*{fields[__${itemStat.index}__].value}">
                </div>

            </div>

但它告诉我这个错误

2018-08-20 09：09：36.000 ERROR 13144 --- [nio-8092-exec-1] oaccC [ . [ . [/] . [dispatcherServlet]：Servlet中的Servlet.service（）[dispatcherServlet] with path []抛出异常[请求处理失败;嵌套异常是org.springframework.beans.InvalidPropertyException：bean类的无效属性'fields [0]'[com.kepler.skeleton.domain.model.Ecran]：非法尝试获取属性'fields'引发异常;嵌套异常是org.springframework.beans.InvalidPropertyException：bean类的无效属性'fields [0]'[com.kepler.skeleton.domain.model.Ecran]：无法从大小为0的Set中获取索引为0的元素，使用属性路径'fields [0]']带有根本原因org.springframework.beans.InvalidPropertyException：bean类的无效属性'fields [0]'[com.kepler.skeleton.domain.model.Ecran]：无法获取带索引的元素来自0的Set 0，使用org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyValue（AbstractNestablePropertyAccessor.java:664）〜[spring-beans-5.0.8.RELEASE.jar：5.0]中的属性路径'fields [0]'访问 . 8.RELEASE]在org.springframework.beans.AbstractNestablePropertyAccessor的org.springframework.beans.AbstractNestablePropertyAccessor.getNestedPropertyAccessor（AbstractNestablePropertyAccessor.java:839）〜[spring-beans-5.0.8.RELEASE.jar：5.0.8.RELEASE] . getPropertyAccessorForPropertyPath（AbstractNestablePropertyAccessor.java:816)~ [spring-beans -5.0.8.RELEASE.jar：5.0.8.RELEASE]在org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue（AbstractNestablePropertyAccessor.java:256）〜[spring-beans-5.0.8.RELEASE.jar：5.0.8 . 发布org.springframework.valid.EringProperty.beans.AbstractPropertyAccessor.setPropertyValues（AbstractPropertyAccessor.java:97）〜[spring-beans-5.0.8.RELEASE.jar：5.0.8.RELEASE] org.springframework.validation.DataBinder.applyPropertyValues（在org.springframework.validation.DataBinder.doBind（DataBinder.java:735）〜[spring-context-5.0]的DataBinder.java:839)~ [spring-context-5.0.8.RELEASE.jar：5.0.8.RELEASE] .8.RELEASE.jar：5.0.8.RELEASE]在org.springframework.web.bind.WebDataBinder.doBind（WebDataBinder.java:197）〜[spring-web-5.0.8.RELEASE.jar：5.0.8 . 发布在org.springframework.web.servlet上的org.springframework.web.bind.ServletRequestDataBinder.bind（ServletRequestDataBinder.java:107）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] . mvc.method.annotation.ServletModelAttributeMethodProcessor.bindRequestParameters（S ervletModelAttributeMethodProcessor.java:157)~ [spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE] org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument（ModelAttributeMethodProcessor.java:152)~ [spring -web-5.0.8.RELEASE.jar：5.0.8.RELEASE] at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument（HandlerMethodArgumentResolverComposite.java:124)~ [spring-web-5.0.8.RELEASE . jar：5.0.8.RELEASE] at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues（InvocableHandlerMethod.java:161)~ [spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] at at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest（InvocableHandlerMethod.java:131）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] org.springframework.web.servlet.mvc org.springfr中的.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle（ServletInvocableHandlerMethod.java:102）〜[spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE] org.springframework.web.servlet上的amework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod（RequestMappingHandlerAdapter.java:877)~ [spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE] org.springframework.web.servlet.mvc.method上的.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal（RequestMappingHandlerAdapter.java:783)~ [spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE] . 在org.springframework.web.servlet.DispatcherServlet.doDispatch（DispatcherServlet.java:991）的AbstractHandlerMethodAdapter.handle（AbstractHandlerMethodAdapter.java:87）〜[spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE]〜 [spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE]在org.springframework.web.servlet.DispatcherServlet.doService（DispatcherServlet.java:925)~ [spring-webmvc-5.0.8.RELEASE . jar：5.0.8.RELEASE] atorg.springframework.web.servlet.FrameworkServlet.processRequest（FrameworkServlet.java:974）〜[spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE] org.springframework.web.servlet.FrameworkServlet.doPost （FrameworkServlet.java:877）〜[spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE]在javax.servlet.http.HttpServlet.service（HttpServlet.java:661）〜[tomcat-embed- core-8.5.32.jar：8.5.32] at org.springframework.web.servlet.FrameworkServlet.service（FrameworkServlet.java：851）〜[spring-webmvc-5.0.8.RELEASE.jar：5.0.8.RELEASE ]在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain）的javax.servlet.http.HttpServlet.service（HttpServlet.java:742）〜[tomcat-embed-core-8.5.32.jar：8.5.32] .java：231）〜[tomcat-embed-core-8.5.32.jar：8.5.32]在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed-core- 8.5.32.jar：8.5.32] at org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）〜[tomcat-embed-websocket-8.5.32.jar：8 .5.32] org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-8.5.32.jar：8.5.32] at org.apache.catalina.core.ApplicationFilterChain ordo.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:320）〜[[ . ] spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke（FilterSecurityInterceptor.java:127)~ [spring-security-web -5.0.7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter（FilterSecurityInterceptor.java:91）〜[spring-security-web-5.0.7 . RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7 .RELEASE]在org.springframework.security.web.acce在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy）的ss.ExceptionTranslationFilter.doFilter（ExceptionTranslationFilter.java:119）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] .java：334）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] org.springframework.security.web.session.SessionManagementFilter.doFilter（SessionManagementFilter.java:137)~ [ spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] at org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.0 .7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter（AnonymousAuthenticationFilter.java:111）〜[spring-security-web-5.0.7.RELEASE.jar： 5.0.7.RELEASE]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] at at org.springframework.securi org.springframework.security.web.FilterChainProxy上的ty.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter（RememberMeAuthenticationFilter.java:150）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter（SecurityContextHolderAwareRequestFilter . java：170）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring -security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter（RequestCacheAwareFilter.java:63）〜[spring-security-web-5.0 . 7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.0 . 7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter（AbstractAuthenticationProcessingFilter.java:200）〜[spring-security-web-5.0.7.RELEASE.jar：5.0 .7.RELEASE] org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] at org .springframework.security.web.authentication.logout.LogoutFilter.doFilter（LogoutFilter.java:116）org.springframework.security.web.FilterChainProxy $ [VirtualFilterChain.doFilter]（[...] - [spring-security-web] -5.0.7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal（HeaderWriterFilter.java:66）〜[spring-security-web-5.0.7.RELEASE . jar：5.0.7.RELEASE] org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:107）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] at org . orframe.springframework.security.web.context上的springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334)~ [spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] .SecurityContextPersistenceFilter.doFilter（SecurityContextPersistenceFilter.java:105）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy . java：334）〜[spring-security-web-5 . 0.7.RELEASE.jar：5.0.7.RELEASE] at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal（WebAsyncManagerIntegrationFilter.java:56）〜[spring-security-web-5.0.7.RELEASE .jar：5.0.7.RELEASE] org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:107）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] at org org.springframework.security.web上的.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334)~ [spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE] . 在org.springframework.security.web.FilterChainProxy.doFilter的FilterChainProxy.doFilterInternal（FilterChainProxy.java:215）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE]（FilterChainProxy.java:178 ）〜[spring-security-web-5.0.7.RELEASE.jar：5.0.7.RELEASE]在org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate（DelegatingFilterProxy.java:357）〜[spring-web-5.0 . 8.RELEASE.jar：5.0.8.RELEASE]在org.springfr orme.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain）中的amework.web.filter.DelegatingFilterProxy.doFilter（DelegatingFilterProxy.java:270)~ [spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] .java：193）〜[tomcat-embed-core-8.5.32.jar：8.5.32]在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed-core- 8.5.32.jar:8.5.32]在org.springframework.web.filter.RequestContextFilter.doFilterInternal（RequestContextFilter.java:99）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] at at org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:107）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE] org.apache.catalina.core.ApplicationFilterChain.internalDoFilter （ApplicationFilterChain.java:193）〜[tomcat-embed-core-8.5.32.jar：8.5.32]在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed- core-8.5.32.jar：8.5.32] at org.springframework.web.filter.HttpP在org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:107）的utFormContentFilter.doFilterInternal（HttpPutFormContentFilter.java:109）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE]〜 [spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE]在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-8.5.32 . jar：8.5.32] org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed-core-8.5.32.jar：8.5.32] org.springframework.web . org.springframework.web.filter.OncePerRequestFilter.doFilter上的filter.HiddenHttpMethodFilter.doFilterInternal（HiddenHttpMethodFilter.java:93）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE]（OncePerRequestFilter.java:107 ）〜[spring-web-5.0.8.RELEASE.jar：5.0.8.RELEASE]在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-8.5 . 32.jar：8.5.32]在org.apache.catalina.core.Applicat ionFilterChain.doFilter（ApplicationFilterChain.java:166)~ [tomcat-embed-core-8.5.32.jar：8.5.32] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal（CharacterEncodingFilter.java:200）〜[spring -web-5.0.8.RELEASE.jar：5.0.8.RELEASE]在org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:107）〜[spring-web-5.0.8.RELEASE.jar： 5.0.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-8.5.32.jar：8.5.32]在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed-core-8.5.32.jar ：8.5.32] org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:198）〜[tomcat-embed-core-8.5.32.jar：8.5.32] org.apache.catalina.core .standardContextValve.invoke（StandardContextValve.java:96）[tomcat-embed-core-8.5.32.jar：8.5.32] at org.apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:493）[tomcat- embed-core-8.5.32.jar：8.5.32] at org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:140）[tomcat-embed-core-8.5.32.jar：8.5.32] at org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:81）[tomcat-embed-core-8.5.32.jar：8.5.32] at org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve） .java：87）[tomcat-embed-core-8.5.32.jar：8.5.32] org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:342）[tomcat-embed -core-8.5.32.jar：8.5.32]在org.apache.coyote.http11.Http11Processor.service（Http11Processor.java:800）[tomcat-embed-core-8.5.32.jar：8.5.32] at at org.apache.coyote.AbstractProcessorLight.process（AbstractProcessorLight.java:66）[tomcat-embed-core-8.5.32.jar：8.5.32] at org.apache.coyote.AbstractProtocol $ ConnectionHandler.process（AbstractProtocol.java： 800）[tomcat-embed-core-8.5.32.jar：8.5.32] at org.apache.tomcat.util.net.NioEndpoint $ SocketProcessor.doRun（NioEndpoint.java:1471）[tomcat-embed-core-8.5 .32.jar：8.5.32]在java的org.apache.tomcat.util.net.SocketProcessorBase.run（SocketProcessorBase.java:49）[tomcat-embed-core-8.5.32.jar：8.5.32] . util.concurrent.ThreadPoolExecutor.runWorker（未知来源）[na：1.8.0_111] at java.util.concurrent.ThreadPoolExecutor $ Worker.run（未知来源）[na：1.8.0_111] at org.apache.tomcat.util . threads.TaskThread $ WrappingRunnable.run（TaskThread.java:61）[tomcat-embed-core-8.5.32.jar：8.5.32] at java.lang.Thread.run（Unknown Source）[na：1.8.0_111]