Hi Jörg,
Ok, I wrote a small self-contained class to illustrate the issue:
import java.io.EOFException;
import java.io.ObjectInputStream;
import java.util.LinkedList;
import java.util.List;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.thoughtworks.xstream.XStream;
public class TestXStreamReferencing
{
//~ Statics
------------------------------------------------------------------
static private final Logger LOG =
LoggerFactory.getLogger(TestXStreamReferencing.class);
//~ Methods
------------------------------------------------------------------
public static void main(String[] args)
{
try
{
String xml = StringUtils.join(new String[] {
"<list>",
" <typeA/>",
" <typeA/>",
" <typeB>",
" <items>",
" <typeA reference=\"../../../typeA[2]\"/>",
" </items>",
" </typeB>",
"</list>"
}, "\n");
// Read objects.
XStream xsUsersAndGroups = new XStream();
xsUsersAndGroups.alias("typeA", TypeA.class);
xsUsersAndGroups.alias("typeB", TypeB.class);
ObjectInputStream isUsersAndGroups =
xsUsersAndGroups.createObjectInputStream(IOUtils.toInputStream(xml));
try
{
while (true)
{
Object nextObject = isUsersAndGroups.readObject();
LOG.info("read: {}", nextObject);
}
}
catch (EOFException e)
{
}
}
catch (Throwable t)
{
LOG.error(t.getMessage(), t);
}
}
//~ Inner Classes
------------------------------------------------------------
static class TypeA
{
}
static class TypeB
{
//~ Members
----------------------------------------------------------------
private List<TypeA> items;
//~ Constructors
-----------------------------------------------------------
public TypeB()
{
this.items = new LinkedList<TypeA>();
}
//~ Methods
----------------------------------------------------------------
public List<TypeA> getItems()
{
return items;
}
public void setItems(List<TypeA> items)
{
this.items = items;
}
}
}
And the error I get:
ERROR [main] (TestXStreamReferencing.java:64) - Invalid reference
---- Debugging information ----
reference : ../../../typeA[2]
class : java.util.ArrayList
required-type : java.util.ArrayList
converter-type :
com.thoughtworks.xstream.converters.collections.CollectionConverter
path : /typeB/items/typeA
line number : 6
class[1] : com.wft.lcods.tool.TestXStreamReferencing$TypeB
converter-type[1] :
com.thoughtworks.xstream.converters.reflection.ReflectionConverter
version : null
-------------------------------
com.thoughtworks.xstream.converters.ConversionException: Invalid reference
---- Debugging information ----
reference : ../../../typeA[2]
class : java.util.ArrayList
required-type : java.util.ArrayList
converter-type :
com.thoughtworks.xstream.converters.collections.CollectionConverter
path : /typeB/items/typeA
line number : 6
class[1] : com.wft.lcods.tool.TestXStreamReferencing$TypeB
converter-type[1] :
com.thoughtworks.xstream.converters.reflection.ReflectionConverter
version : null
-------------------------------
at
com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:57)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at
com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.readItem(AbstractCollectionConverter.java:71)
at
com.thoughtworks.xstream.converters.collections.CollectionConverter.addCurrentElementToCollection(CollectionConverter.java:79)
at
com.thoughtworks.xstream.converters.collections.CollectionConverter.populateCollection(CollectionConverter.java:72)
at
com.thoughtworks.xstream.converters.collections.CollectionConverter.populateCollection(CollectionConverter.java:66)
at
com.thoughtworks.xstream.converters.collections.CollectionConverter.unmarshal(CollectionConverter.java:61)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at
com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at
com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshallField(AbstractReflectionConverter.java:355)
at
com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doUnmarshal(AbstractReflectionConverter.java:306)
at
com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:234)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at
com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at
com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:134)
at
com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:32)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1052)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1024)
at com.thoughtworks.xstream.XStream$2.readFromStream(XStream.java:1716)
at
com.thoughtworks.xstream.core.util.CustomObjectInputStream.readObjectOverride(CustomObjectInputStream.java:104)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:363)
at
com.wft.lcods.tool.TestXStreamReferencing.main(TestXStreamReferencing.java:53)
Thanks for your help!
Michael
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