XStream
  1. XStream
  2. XSTR-554

XStream fromXml of groovy objects fails within a syncronsized map

          Details

          • Type: Bug Bug
          • Status: Closed Closed
          • Priority: Major Major
          • Resolution: Cannot Reproduce
          • Affects Version/s: 1.1.3
          • Fix Version/s: 1.2
          • Component/s: None
          • Labels:
            None
          • JDK version and platform:
            JDK 1.6.0_11 on Windows XP

            Description

            re-persisting an object with a package level variable after its been loaded by xstream fails with the following exception:

            ---- Debugging information ----
message             : Could not call
java.util.Collections$SynchronizedMap.writeObject() 
cause-message       : null 
cause-exception     : java.lang.reflect.InvocationTargetException 
------------------------------- org.groovymud.shell.telnetd.MudShell 
com.thoughtworks.xstream.converters.ConversionException: Could not call
java.util.Collections$SynchronizedMap.writeObject()
---- Debugging information ----
message             : Could not call
java.util.Collections$SynchronizedMap.writeObject() 
cause-message       : null 
cause-exception     : java.lang.reflect.InvocationTargetException 
-------------------------------
	at
com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:92)
	at
com.thoughtworks.xstream.converters.reflection.SerializableConverter.marshal(SerializableConverter.java:186)
	at
com.thoughtworks.xstream.core.ReferenceByXPathMarshaller.convertAnother(ReferenceByXPathMarshaller.java:36)
	at
com.thoughtworks.xstream.converters.reflection.ReflectionConverter$1.writeField(ReflectionConverter.java:81)
	at
com.thoughtworks.xstream.converters.reflection.ReflectionConverter$1.visit(ReflectionConverter.java:59)
	at
com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:108)
	at
com.thoughtworks.xstream.converters.reflection.ReflectionConverter.marshal(ReflectionConverter.java:44)
	at
com.thoughtworks.xstream.core.ReferenceByXPathMarshaller.convertAnother(ReferenceByXPathMarshaller.java:36)
	at
com.thoughtworks.xstream.converters.reflection.ReflectionConverter$1.writeField(ReflectionConverter.java:81)
	at
com.thoughtworks.xstream.converters.reflection.ReflectionConverter$1.visit(ReflectionConverter.java:59)
	at
com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:108)
	at
com.thoughtworks.xstream.converters.reflection.ReflectionConverter.marshal(ReflectionConverter.java:44)
	at
com.thoughtworks.xstream.core.ReferenceByXPathMarshaller.convertAnother(ReferenceByXPathMarshaller.java:36)
	at com.thoughtworks.xstream.core.TreeMarshaller.start(TreeMarshaller.java:46)
	at
com.thoughtworks.xstream.core.ReferenceByXPathMarshallingStrategy.marshal(ReferenceByXPathMarshallingStrategy.java:17)
	at com.thoughtworks.xstream.XStream.marshal(XStream.java:476)
	at com.thoughtworks.xstream.XStream.marshal(XStream.java:466)
	at com.thoughtworks.xstream.XStream.toXML(XStream.java:458)
	at
org.groovymud.object.registry.MudObjectAttendant.savePlayerData(MudObjectAttendant.java:260)
	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 org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:86)
	at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:230)
	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:912)
	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:756)
	at
org.codehaus.groovy.runtime.InvokerHelper.invokePojoMethod(InvokerHelper.java:766)
	at
org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:754)
	at
org.codehaus.groovy.runtime.ScriptBytecodeAdapter.invokeMethodN(ScriptBytecodeAdapter.java:170)
	at commands.player.save.run(save.groovy:13)
	at groovy.util.GroovyScriptEngine.run(GroovyScriptEngine.java:386)
	at
org.groovymud.shell.command.CommandInterpreter.doCommand(CommandInterpreter.java:165)
	at
org.groovymud.shell.command.CommandInterpreter$1.run(CommandInterpreter.java:113)
	at java.security.AccessController.doPrivileged(Native Method)
	at javax.security.auth.Subject.doAsPrivileged(Subject.java:454)
	at
org.groovymud.shell.command.CommandInterpreter.doShellCommand(CommandInterpreter.java:104)
	at org.groovymud.shell.telnetd.MudShell.handleRequest(MudShell.java:58)
	at org.groovymud.shell.telnetd.MudShell.run(MudShell.java:32)
	at net.wimpi.telnetd.net.Connection.run(Connection.java:119)
Caused by: java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at
com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:88)
	... 39 more
Caused by: com.thoughtworks.xstream.converters.ConversionException: Could
not call java.util.Collections$SynchronizedMap.writeObject()

            the groovy object is in a synchronized map and has a package level variable which, in another exception I do not have to hand, seems to be the cause of the problem.

            Reproduce (using Java, not Groovy - you should load the groovy object using the GroovyScriptEngine):

            1. persist an object using XStream with a synchronized map that contains a groovy object with a package protected variable in it
            2. load that object using fromXML with the same XStream object
            3. try to persist that object using the same XStream object

            Interestingly, if you use a different XStream object, as suggested at

            http://www.bobsgear.com/display/bobsgear/Could+not+get+field+class+error+with+xstream

            ... this works fine. I have worked round this for now with that exact solution.

              People

              • Assignee:
                Jörg Schaible
                Reporter:
                Matthew Corby-Eaglen
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                Watchers:
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                Dates

                • Created:
                  Updated:
                  Resolved: