Xstream 对象转xml 出现Cannot reference implicit element

调用 xStream 的 toXML方法，就出现如下错误，汗啊
toXML 传入的是一个action：

com.thoughtworks.xstream.converters.ConversionException: Could not call java.util.concurrent.ConcurrentHashMap.writeObject() : Could not call java.util.Collections$SynchronizedList.writeObject() : Cannot reference implicit element
---- Debugging information ----
implicit-element : []

referencing-element : /com.travelsky.tdp.pkgStock.view.travelb2b.PproductInfoAction/container/factories/entry/com.opensymphony.xwork2.inject.ContainerBuilder_-4/outer-class/factories/entry[2]/com.opensymphony.xwork2.inject.Scope_-2_-1/instance/reflectionProvider/ognlUtil/defaultConverter/typeConverter/defaultTypeConverter/objectFactory/appContext/servletContext/context/attributes/java.util.concurrent.ConcurrentHashMap/org.apache.catalina.util.DefaultAnnotationProcessor/context/bindings/entry/org.apache.naming.NamingEntry/value/bindings/entry/org.apache.naming.NamingEntry/value/cachedChannelsTransactional/dynamic-proxy/handler/target/_connection/_workService/executor/workers/java.util.concurrent.ThreadPoolExecutor_-Worker/thread/group/threads/net.sf.ehcache.store.DiskStore_-SpoolAndExpiryThread/outer-class/freeSpace/java.util.Collections_-SynchronizedCollection/default/mutex

message : Could not call java.util.Collections$SynchronizedList.writeObject()
cause-exception : com.thoughtworks.xstream.core.AbstractReferenceMarshaller$ReferencedImplicitElementException

cause-message : Cannot reference implicit element

message : Could not call java.util.concurrent.ConcurrentHashMap.writeObject()
cause-exception : com.thoughtworks.xstream.converters.ConversionException
cause-message : Could not call java.util.Collections$SynchronizedList.writeObject() : Cannot reference implicit element
---- Debugging information ----
implicit-element : []

referencing-element : /com.travelsky.tdp.pkgStock.view.travelb2b.PproductInfoAction/container/factories/entry/com.opensymphony.xwork2.inject.ContainerBuilder_-4/outer-class/factories/entry[2]/com.opensymphony.xwork2.inject.Scope_-2_-1/instance/reflectionProvider/ognlUtil/defaultConverter/typeConverter/defaultTypeConverter/objectFactory/appContext/servletContext/context/attributes/java.util.concurrent.ConcurrentHashMap/org.apache.catalina.util.DefaultAnnotationProcessor/context/bindings/entry/org.apache.naming.NamingEntry/value/bindings/entry/org.apache.naming.NamingEntry/value/cachedChannelsTransactional/dynamic-proxy/handler/target/_connection/_workService/executor/workers/java.util.concurrent.ThreadPoolExecutor_-Worker/thread/group/threads/net.sf.ehcache.store.DiskStore_-SpoolAndExpiryThread/outer-class/freeSpace/java.util.Collections_-SynchronizedCollection/default/mutex

at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:103)
at com.thoughtworks.xstream.converters.reflection.SerializableConverter.doMarshal(SerializableConverter.java:215)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.MapConverter.marshal(MapConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.MapConverter.marshal(MapConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.core.TreeMarshaller.start(TreeMarshaller.java:98)
at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.marshal(AbstractTreeMarshallingStrategy.java:38)
at com.thoughtworks.xstream.XStream.marshal(XStream.java:837)
at com.thoughtworks.xstream.XStream.marshal(XStream.java:826)
at com.thoughtworks.xstream.XStream.toXML(XStream.java:815)
at com.travelsky.tdp.pkgStock.logic.util.FM_XMLTools.Object2Xml(FM_XMLTools.java:39)
at com.travelsky.tdp.pkgStock.rest.ContentTypeInterceptor.handleResult(ContentTypeInterceptor.java:67)
at com.travelsky.tdp.pkgStock.rest.ContentTypeInterceptor.intercept(ContentTypeInterceptor.java:54)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:246)
at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:563)
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:99)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at cn.org.rapid_framework.web.scope.FlashFilter.doFilterInternal(FlashFilter.java:28)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at javacommon.filter.LoggerMDCFilter.doFilterInternal(LoggerMDCFilter.java:54)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:877)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:594)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1675)
at java.lang.Thread.run(Thread.java:619)

Caused by: com.thoughtworks.xstream.converters.ConversionException: Could not call java.util.Collections$SynchronizedList.writeObject() : Cannot reference implicit element
---- Debugging information ----
implicit-element : []

referencing-element : /com.travelsky.tdp.pkgStock.view.travelb2b.PproductInfoAction/container/factories/entry/com.opensymphony.xwork2.inject.ContainerBuilder_-4/outer-class/factories/entry[2]/com.opensymphony.xwork2.inject.Scope_-2_-1/instance/reflectionProvider/ognlUtil/defaultConverter/typeConverter/defaultTypeConverter/objectFactory/appContext/servletContext/context/attributes/java.util.concurrent.ConcurrentHashMap/org.apache.catalina.util.DefaultAnnotationProcessor/context/bindings/entry/org.apache.naming.NamingEntry/value/bindings/entry/org.apache.naming.NamingEntry/value/cachedChannelsTransactional/dynamic-proxy/handler/target/_connection/_workService/executor/workers/java.util.concurrent.ThreadPoolExecutor_-Worker/thread/group/threads/net.sf.ehcache.store.DiskStore_-SpoolAndExpiryThread/outer-class/freeSpace/java.util.Collections_-SynchronizedCollection/default/mutex

message : Could not call java.util.Collections$SynchronizedList.writeObject()
cause-exception : com.thoughtworks.xstream.core.AbstractReferenceMarshaller$ReferencedImplicitElementException

cause-message : Cannot reference implicit element

at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:103)
at com.thoughtworks.xstream.converters.reflection.SerializableConverter.doMarshal(SerializableConverter.java:215)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:56)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.ArrayConverter.marshal(ArrayConverter.java:45)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.marshal(CollectionConverter.java:55)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.extended.DynamicProxyConverter.marshal(DynamicProxyConverter.java:60)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.marshal(CollectionConverter.java:55)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.MapConverter.marshal(MapConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.MapConverter.marshal(MapConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshallField(AbstractReflectionConverter.java:157)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.writeField(AbstractReflectionConverter.java:148)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$2.visit(AbstractReflectionConverter.java:118)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:129)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doMarshal(AbstractReflectionConverter.java:100)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:68)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.reflection.SerializableConverter$1.writeToStream(SerializableConverter.java:104)
at com.thoughtworks.xstream.core.util.CustomObjectOutputStream.writeObjectOverride(CustomObjectOutputStream.java:84)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:322)
at java.util.concurrent.ConcurrentHashMap.writeObject(ConcurrentHashMap.java:1247)
at sun.reflect.GeneratedMethodAccessor282.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:99)
... 176 more

Caused by: com.thoughtworks.xstream.core.AbstractReferenceMarshaller$ReferencedImplicitElementException: Cannot reference implicit element
---- Debugging information ----
implicit-element : []

referencing-element : /com.travelsky.tdp.pkgStock.view.travelb2b.PproductInfoAction/container/factories/entry/com.opensymphony.xwork2.inject.ContainerBuilder_-4/outer-class/factories/entry[2]/com.opensymphony.xwork2.inject.Scope_-2_-1/instance/reflectionProvider/ognlUtil/defaultConverter/typeConverter/defaultTypeConverter/objectFactory/appContext/servletContext/context/attributes/java.util.concurrent.ConcurrentHashMap/org.apache.catalina.util.DefaultAnnotationProcessor/context/bindings/entry/org.apache.naming.NamingEntry/value/bindings/entry/org.apache.naming.NamingEntry/value/cachedChannelsTransactional/dynamic-proxy/handler/target/_connection/_workService/executor/workers/java.util.concurrent.ThreadPoolExecutor_-Worker/thread/group/threads/net.sf.ehcache.store.DiskStore_-SpoolAndExpiryThread/outer-class/freeSpace/java.util.Collections_-SynchronizedCollection/default/mutex

at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:58)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:78)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:63)
at com.thoughtworks.xstream.converters.reflection.SerializableConverter$1.defaultWriteObject(SerializableConverter.java:176)
at com.thoughtworks.xstream.core.util.CustomObjectOutputStream.defaultWriteObject(CustomObjectOutputStream.java:80)
at java.util.Collections$SynchronizedCollection.writeObject(Collections.java:1602)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:99)
... 350 more

<?xml version="1.0" encoding="UTF-8" ?>

null

2014-05-14 14:34:14,680 [1167244/[SHA325]stest/127.0.0.1/20bb88da3c7442988693c52d3eb8dc6f - /fproduct/travelb2b/pproduct-info!list.shtml] ERROR org.apache.struts2.dispatcher.Dispatcher - Exception occurred during processing request: getWriter() has already been called for this response
java.lang.IllegalStateException: getWriter() has already been called for this response
at org.apache.catalina.connector.Response.getOutputStream(Response.java:580) ~[catalina.jar:6.0.35]
at org.apache.catalina.connector.ResponseFacade.getOutputStream(ResponseFacade.java:183) ~[catalina.jar:6.0.35]
at com.travelsky.tdp.pkgStock.rest.ContentTypeInterceptor.handleResult(ContentTypeInterceptor.java:76) ~[ContentTypeInterceptor.class:na]
at com.travelsky.tdp.pkgStock.rest.ContentTypeInterceptor.intercept(ContentTypeInterceptor.java:54) ~[ContentTypeInterceptor.class:na]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:246) ~[xwork-core-2.3.15.1.jar:2.3.15.1]
at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54) ~[struts2-core-2.3.15.1.jar:2.3.15.1]
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:563) ~[struts2-core-2.3.15.1.jar:2.3.15.1]
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77) [struts2-core-2.3.15.1.jar:2.3.15.1]
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:99) [struts2-core-2.3.15.1.jar:2.3.15.1]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:6.0.35]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:6.0.35]
at cn.org.rapid_framework.web.scope.FlashFilter.doFilterInternal(FlashFilter.java:28) [rapid-core-4.0.3.jar:na]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) [spring-web-3.0.5.RELEASE.jar:3.0.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:6.0.35]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:6.0.35]
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) [spring-orm-3.0.5.RELEASE.jar:3.0.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) [spring-web-3.0.5.RELEASE.jar:3.0.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:6.0.35]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:6.0.35]
at javacommon.filter.LoggerMDCFilter.doFilterInternal(LoggerMDCFilter.java:54) [stock-core-rapidframework-1.1-SNAPSHOT.jar:na]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) [spring-web-3.0.5.RELEASE.jar:3.0.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:6.0.35]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:6.0.35]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) [spring-web-3.0.5.RELEASE.jar:3.0.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) [spring-web-3.0.5.RELEASE.jar:3.0.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:6.0.35]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:6.0.35]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) [catalina.jar:6.0.35]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) [catalina.jar:6.0.35]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) [catalina.jar:6.0.35]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [catalina.jar:6.0.35]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [catalina.jar:6.0.35]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) [catalina.jar:6.0.35]
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:877) [tomcat-coyote.jar:6.0.35]
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:594) [tomcat-coyote.jar:6.0.35]
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1675) [tomcat-coyote.jar:6.0.35]
at java.lang.Thread.run(Thread.java:619) [na:1.6.0_10-rc2]
2014-5-14 14:34:14 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet default threw exception
java.lang.IllegalStateException
at org.apache.catalina.connector.ResponseFacade.sendError(ResponseFacade.java:407)
at org.apache.struts2.dispatcher.Dispatcher.sendError(Dispatcher.java:906)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:586)
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:99)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at cn.org.rapid_framework.web.scope.FlashFilter.doFilterInternal(FlashFilter.java:28)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at javacommon.filter.LoggerMDCFilter.doFilterInternal(LoggerMDCFilter.java:54)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:877)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:594)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1675)
at java.lang.Thread.run(Thread.java:619)

（哥们没有提供源代码）提供点解决此问题的思路（希望能帮助到你）：
public void print2Screen(HttpServletResponse resp,String encodeString,String[] htmlCommands) throws IOException{
resp.setCharacterEncoding(encodeString);
ServletOutputStream httpOutput= [color=red]resp.getOutputStream();[/color]
for(String temp:htmlCommands)
[color=red] httpOutput.write(temp.getBytes());[/color] }

深层原理:
1.Servlet规范说明，不能既调用 response.getOutputStream()，又调用response.getWriter()，无论先调用哪一个，在调用第二个时候应会抛出 IllegalStateException.
2.servlet代码中有out.write(””)，这个和JSP中缺省调用的response.getOutputStream()产生冲突.
因为在jsp中，out变量是通过response.getWriter得到的，在程序中既用了 response.getOutputStream，又用了out变量，故出现以上错误。

解决:
法一:在JSP文件中,加入下面两句
<%
out.clear();
out = pageContext.pushBody();
%>

此法的缺陷:
很多开发项目并不是JSP前端,如freemarker,velocity等
造成问题的"response.getOutputStream()"并未被写在JSP里,而是写在servlet/action里

法二: 在action中,不要return 回具体的result文件,而是return null
//return SUCCESS;
[color=red] return null;[/color]

还有一种可能是在数据传递的时候没有序列化要以对象模型的实体类

属性不能解析（反射），注解的方式吗，你没有代码，这个问题真不知道具体在哪里，只能自己找了，给你一篇文章看下试试：http://www.oschina.net/code/snippet_116183_14202

这个是因为有List属性，但是没有annotation说明List怎么转换

可以将所有的List属性都默认设置= new ArrayList(); 这样再试试，不要有为Null的List。