Title: Message
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Hi David
Brian is right. In fact dom4j cannot determine by
itself when the end of a document occurs since an XML document can contain other
stuff after the end tag, e.g. comments or processing instructions.
<!-- this is a valid XML document
-->
<something>
hello
</something>
<!-- this is a comment -->
<?stylesheet file="foo.xslt"?>
As Brian says, using some kind of protocol is
required to determine the length of the XML file - such as using a content
length in the HTTP protocol. This simple mechanism can be implemented on top of
sockets using streams.
If in doubt though, use HTTP (or Servlets) to do
all this for you.
James
----- Original Message -----
Sent: Tuesday, March 26, 2002 9:59
PM
Subject: Re: [dom4j-user] Help reading
xml from socket
David,
This is a common problem people
encounter when working with sockets and probably not a dom4j issue.
The socket essentially stays open and there will not be a way to
determine when the client is done sending data unless you investigate the data
itself. Flush() was a good try but it will not solve this problem.
I doubt that dom4j is doing a lot of intelligence to find out when
the whole document has been collected (i.e. looking for the end of the root
tag, etc) You may want to consider implementing the HTTP protocol and sending
the data off after you collect it. HTTP has a content-length header
variable so you know when to stop reading. Or, you could look for the
start and end tags occuring in the data yourself and then send the collected
data on to dom4j.
Outside of your problem, for what it is worth- piping
data right from a socket into dom4j is probably not the best design- I'd focus
on collecting the data first like I mentioned above and then continuing.
This will give you an adequate abstraction layer for better error
handling and so forth. The current design is too tied to the network
layer for my preference.
Good luck!
Brian
David Hooker
wrote:
000801c1d50c$e495c930$6901a8c0@DHOOKER type="cite">
I have a socket
from which I'm receiving xml. I need to create a Document object from
this. Once the xml comes in, I need to leave the socket open for other
data to come in. Here's the receiving code:
private Document getDocumentFromStream(InputStream
xmlStream)
{
Document doc =
null;
SAXReader reader = new
SAXReader();
reader.setValidation(false);
try
{
doc
= reader.read(xmlStream);
}
catch(DocumentException
de)
{
System.out.println("error");
}
return
doc;
}
Now, the sender
is calling flush() on the stream after it sends the xml,
but it isn't closing the socket. Does the SAXReader know when the end
of the xml data is so that it can construct and return the Document -
without me having to close the stream to signal it that there is no more
data?
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