Sent: Tuesday, September 24, 2002 7:43
PM
Subject: RE: How to get the error code
during SAX parse?
I am not sure what you mean.
XMLScanner traps the exception when the target file does not exist
(for example). This means that the caller (eg DOMCount) does not get
told the file does not exist - only that 'there was an error' via the call
back.
There is no difference in
the behaviour the caller sees if there error was due to file not existing or
document being malformed in terms of whether or not an exception is thrown or
the callback is called.
In
other words:
- 'fundamental errors
with finding the source data' are reported via the call back 'as parsing
errors' if I understand what you are saying.
- in DOMCount the catches around the call to parse documents will only
catch something if the code was changed to try parsing another document whilst
a parse is in progress or similar.
In the case that the target files does not exist the caller has no way
of knowing what the actual error was without parsing the error message (which
is a bit ugly) ...
Are you
implying that the exception handling in XMLScanner::scanDocument should
actually be removed/altered to allow these 'fundamental' errors to be thrown
back to the caller?
|
| Dean Roddey
<[EMAIL PROTECTED]>
25/09/2002 10:13 AM
Please respond to xerces-c-dev
|
To:
[EMAIL PROTECTED]
cc:
Subject: RE: How to get the
error code during SAX parse? |
As I said, exceptions are not used to report
parsing errors, only fundamental errors with finding the source data, so the
catch after the parse is irrelevant for parsing errors. Look at the error
handler code for the DOMPrint and DOMCount examples.
-------------------------------------
Dean Roddey
The Charmed Quark Controller
[EMAIL PROTECTED]
www.charmedquark.com
-----Original Message-----
From:
[EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, September 24, 2002 4:30 PM
To:
[EMAIL PROTECTED]
Cc:
[EMAIL PROTECTED]
Subject: RE: How to get the error code
during SAX parse?
But I'm saying none of the parsers don't
supply the information I'd like (ie the actual parsing error that occurred)
because the underlying scanner which is used by both DOM and SAX parsers
throws the error away ...
See XMLScanner::scanDocument - the
exception handling that is invoked (if file does not exist for
example).
|
| Dean Roddey
<[EMAIL PROTECTED]>
25/09/2002 09:23 AM
Please respond to xerces-c-dev
|
To:
[EMAIL PROTECTED]
cc:
Subject:
RE: How to get the error code during SAX
parse? |
I can't speak to the SAX2 part, since I've not looked
at that variant. The parser itself does provide the information you want, but
if the SAX2 specification (which the Xerces team does not define) doesn't
provide a way to pass it on, then there's not much the parser can do about it.
-------------------------------------
Dean Roddey
The Charmed Quark
Controller
[EMAIL PROTECTED]
www.charmedquark.com
-----Original Message-----
From:
[EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, September 24, 2002 4:13 PM
To:
[EMAIL PROTECTED]
Subject: RE: How to get the error code
during SAX parse?
Can we get some enlightenment on this (for
the dummies!).
When you say the pluggable error call backs, do
you mean the things you set by calling SAX2XMLReader::setErrorHandler or
SAXParser::setErrorHandler?
If so, then these are passed a
SAXParseException object which does not have an error code.
If not,
which example should we look at?
>From previous discussions,
even if the SAXParseException object contained an error code it would only be
one of
XMLErrs::XMLException_Fatal
XMLErrs::XMLException_Error
XMLErrs::XMLException_Warning
because XMLScanner::scanDocument
basically chucks away the actual error.
So, to get the actual
error code that occurred during a parse you have to hack the Xerces code base
...
Would it make sense if the scanner passed through the actual
error code to XMLScanner::emitError and thence to its error reporter?
Then each of the error reporters for each parser can take the
appropriate action (and one could then simply subclass the relevant parser and
overload the error function to trap the actual error code).
To
me there is a bit of an issue in that it is not easy to take programatic
action according to the parser failure (eg take action depending if document
was well formed but not valid versus malformed versus file does not
exist).
What do people think?
Am I
missing something?
|
| Dean Roddey
<[EMAIL PROTECTED]>
25/09/2002 08:27 AM
Please respond to xerces-c-dev
|
To:
[EMAIL PROTECTED]
cc:
Subject:
RE: How to get the error code during SAX
parse? |
Errors are not reported via
the exceptions, they are reported via pluggable error callbacks. An exception
can only report one error, because it unwinds the stack. The callbacks allow
the parser to continue through more than one error (if you tell it that's ok
to do.) Look at the sample programs, which clearly show how this is
done.
-------------------------------------
Dean Roddey
The Charmed Quark
Controller
[EMAIL PROTECTED]
www.charmedquark.com
-----Original Message-----
From: Scot
Nielsen [mailto:[EMAIL PROTECTED]]
Sent: Tuesday,
September 24, 2002 3:09 PM
To: 'Xerces-Dev
(E-mail)'
Subject: How to get the error code during SAX
parse?
Can someone enlighten me please?
There's no error code value in the SaxParseException class...
Are all error codes for internal
use only?
Many thanks, Scot
Nielsen
