XML Serialization Weird Exception

I was testing XML Serialization to assess if it fits my needs. I coded two
methods, one dumping the XML serialized object to a file, and the other that
recreates the object:

static Graph Awake(string filename)
{
System.Xml.Serialization.XmlSerializer s = new
System.Xml.Serialization.XmlSerializer(typeof(Graph));
System.IO.TextReader r = new System.IO.StreamReader(filename);

object res = s.Deserialize(r);
r.Close();

return (Graph) res;
}

static void Hibernate(string filename, Graph graph)
{
System.Xml.Serialization.XmlSerializer s = new
System.Xml.Serialization.XmlSerializer(typeof(Graph));
System.IO.TextWriter w = new System.IO.StreamWriter(filename, false);

s.Serialize(w, graph);

w.Close();
}


If I run those methods separately, they work fine.

However, if I run Hibernate and then Awake, Awake throws an exception...
Furthermore, if I command Hibernate to dump the XML data to a file other
than the one Awake is going to read from, Awake fails again with the same
error.

Any ideas? Bug?

Regards,
Manuel.

HakonB
Wed Feb 16 09:09:47 CST 2005

Could it be because the the reader isn't garbage collected yet and
still holds a reference to the file?

Try to put a w = null after you close the writer and perhaps a
GC.Collect() as well. Or you could open the file with sharing set to
FileShare.Read.

Regards,
HakonB

ManuelVzquez
Wed Feb 16 09:45:06 CST 2005

:(

I forgot to mention I did that. Actually, I have tried lots of hacks to make
this work.
Besides, regardless whether the writer is collected or not, I closed it, so
it should have clear any references to the file/stream.

Thanks,
Manuel.

"HakonB" wrote:

> Could it be because the the reader isn't garbage collected yet and
> still holds a reference to the file?
>
> Try to put a w = null after you close the writer and perhaps a
> GC.Collect() as well. Or you could open the file with sharing set to
> FileShare.Read.
>
> Regards,
> HakonB
>
>

ManuelVzquez
Thu Feb 17 15:53:03 CST 2005

This the message:

There is an error in XML document (4, 16).

at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader
xmlReader, St
ring encodingStyle, XmlDeserializationEvents events)
at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader
xmlReader, St
ring encodingStyle)
at System.Xml.Serialization.XmlSerializer.Deserialize(TextReader
textReader)
at CPN_WF_Test.Class1.Awake(String filename) in
d:\users\manu\programming\tes
ts\cpn wf test\class1.cs:line 17
at CPN_WF_Test.Class1.TestAwake() in d:\users\manu\programming\tests\cpn
wf t
est\class1.cs:line 44
at CPN_WF_Test.Class1.Main(String[] args) in
d:\users\manu\programming\tests\
cpn wf test\class1.cs:line 124

"HakonB" wrote:

> Hello Manuel,
>
> Which exception is thrown?
>
> Regards,
> HakonB
>

ManuelVzquez
Fri Feb 18 16:07:04 CST 2005

I have verified it.
The flush trick didn't make it.

I think this is a BUG. Do you?

Manuel.

"Matt Berther" wrote:

> Hello Manuel,
>
> Have you verified that a complete document is in fact saved when you call
> Hibernate? Between Hibernate and Awake, check and make sure that the complete
> file is written out (Im guessing its not).
>
> You might try something along this line:
>
> static void Hibernate(string filename, Graph graph)
> {
> XmlSerializer s = new XmlSerializer(typeof(Graph));
> TextWriter writer = new StreamWriter(filename, false);
> s.Serialize(writer, graph);
>
> writer.Flush();
> writer.Close();
> }
>
> The trick is probably in the Flush command. I cant count how many times Ive
> been bitten by that.
>
> --
> Matt Berther
> http://www.mattberther.com
>
> > This the message:
> >
> > There is an error in XML document (4, 16).
> >
> > at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader
> > xmlReader, St
> > ring encodingStyle, XmlDeserializationEvents events)
> > at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader
> > xmlReader, St
> > ring encodingStyle)
> > at System.Xml.Serialization.XmlSerializer.Deserialize(TextReader
> > textReader)
> > at CPN_WF_Test.Class1.Awake(String filename) in
> > d:\users\manu\programming\tes
> > ts\cpn wf test\class1.cs:line 17
> > at CPN_WF_Test.Class1.TestAwake() in
> > d:\users\manu\programming\tests\cpn
> > wf t
> > est\class1.cs:line 44
> > at CPN_WF_Test.Class1.Main(String[] args) in
> > d:\users\manu\programming\tests\
> > cpn wf test\class1.cs:line 124
> >
> > "HakonB" wrote:
> >
> >> Hello Manuel,
> >>
> >> Which exception is thrown?
> >>
> >> Regards,
> >> HakonB
>
>
>
>

ManuelVzquez
Sat Feb 19 15:31:06 CST 2005

Mea culpa est.
I found the bug. It's all mine, and I'm ashame having bothered you this long.
It was a global (static) registration scheme that was cleaned after the
Graph object was collected.

I added support for IDisposable interface, called the Dispose method, and
all worked fine.

Sorry,
Manuel.

"Matt Berther" wrote:

> Hello Manuel,
>
> I would propose that you create the smallest duplicatable example of this
> issue and attach all relevant code to your reply to this message. Id be glad
> to look at it more with you.
>
> I can not get the error that you're seeing.
>
> --
> Matt Berther
> http://www.mattberther.com
>
> > I have verified it.
> > The flush trick didn't make it.
> > I think this is a BUG. Do you?
> >
> > Manuel.
> >
> > "Matt Berther" wrote:
> >
> >> Hello Manuel,
> >>
> >> Have you verified that a complete document is in fact saved when you
> >> call Hibernate? Between Hibernate and Awake, check and make sure that
> >> the complete file is written out (Im guessing its not).
> >>
> >> You might try something along this line:
> >>
> >> static void Hibernate(string filename, Graph graph)
> >> {
> >> XmlSerializer s = new XmlSerializer(typeof(Graph));
> >> TextWriter writer = new StreamWriter(filename, false);
> >> s.Serialize(writer, graph);
> >> writer.Flush();
> >> writer.Close();
> >> }
> >> The trick is probably in the Flush command. I cant count how many
> >> times Ive been bitten by that.
> >>
> >> --
> >> Matt Berther
> >> http://www.mattberther.com
> >>> This the message:
> >>>
> >>> There is an error in XML document (4, 16).
> >>>
> >>> at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader
> >>> xmlReader, St
> >>> ring encodingStyle, XmlDeserializationEvents events)
> >>> at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader
> >>> xmlReader, St
> >>> ring encodingStyle)
> >>> at System.Xml.Serialization.XmlSerializer.Deserialize(TextReader
> >>> textReader)
> >>> at CPN_WF_Test.Class1.Awake(String filename) in
> >>> d:\users\manu\programming\tes
> >>> ts\cpn wf test\class1.cs:line 17
> >>> at CPN_WF_Test.Class1.TestAwake() in
> >>> d:\users\manu\programming\tests\cpn
> >>> wf t
> >>> est\class1.cs:line 44
> >>> at CPN_WF_Test.Class1.Main(String[] args) in
> >>> d:\users\manu\programming\tests\
> >>> cpn wf test\class1.cs:line 124
> >>> "HakonB" wrote:
> >>>
> >>>> Hello Manuel,
> >>>>
> >>>> Which exception is thrown?
> >>>>
> >>>> Regards,
> >>>> HakonB
>
>
>
>