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<IMG border="0" height="14" hspace="0" src="resources/close.gif" vspace="0" width="120"><BR></TD><TD align="left" valign="top" width="500"><TABLE border="0" cellpadding="3" cellspacing="0"><TR><TD><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Questions</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif"><UL><LI><A href="#faq-1">Does Xerces-C++ support Schema?</A></LI><LI><A href="#faq-2">Why Xerces-C++ does not support this particular Schema feature?</A></LI><LI><A href="#faq-3">Why does my application crash when instantiating the parser?</A></LI><LI><A href="#faq-4">Is it OK to call the XMLPlatformUtils::Initialize/Terminate pair of routines multiple times in one program?</A></LI><LI><A href="#faq-5">Why does my application crash or hang if XMLPlatformUtils::Initialize()/Terminate() pair is called more than once?</A></LI><LI><A href="#faq-6">Why does my application crash after calling XMLPlatformUtils::Terminate()?</A></LI><LI><A href="#faq-7">I'm suddenly getting segfaults with Xerces-C 2.3.0; why might this be?</A></LI><LI><A href="#faq-8">Is Xerces-C++ thread-safe?</A></LI><LI><A href="#faq-9">I am seeing memory leaks in Xerces-C++. Are they real?</A></LI><LI><A href="#faq-10">I find memory leaks in Xerces-C++. How do I eliminate it?</A></LI><LI><A href="#faq-11">Can Xerces-C++ create an XML skeleton based on a DTD</A></LI><LI><A href="#faq-12">Can I use Xerces-C++ to perform write validation</A></LI><LI><A href="#faq-13">Can I validate the data contained in a DOM tree?</A></LI><LI><A href="#faq-14">How to write out a DOM tree into a string or an XML file?</A></LI><LI><A href="#faq-15">Why does DOMNode::cloneNode() not clone the pointer assigned to a DOMNode via DOMNode::setUserData()?</A></LI><LI><A href="#faq-16">How are entity reference nodes handled in DOM?</A></LI><LI><A href="#faq-17">What kinds of URLs are currently supported in Xerces-C++?</A></LI><LI><A href="#faq-18">How can I add support for URLs with HTTP/FTP protocols?</A></LI><LI><A href="#faq-19">Can I use Xerces-C++ to parse HTML?</A></LI><LI><A href="#faq-20">I keep getting an error: &quot;invalid UTF-8 character&quot;. What's wrong?</A></LI><LI><A href="#faq-21">What encodings are supported by Xerces-C / XML4C?</A></LI><LI><A href="#faq-22">What character encoding should I use when creating XML documents?</A></LI><LI><A href="#faq-23">Is EBCDIC supported?</A></LI><LI><A href="#faq-24">Why does deleting a transcoded string result in assertion on windows?</A></LI><LI><A href="#faq-25">How do I transcode to/from something besides the local code page?</A></LI><LI><A href="#faq-26">Why does setProperty not work?</A></LI><LI><A href="#faq-27">Why does getProperty not work?</A></LI><LI><A href="#faq-28">Why does the parser still try to locate the DTD even validation is turned off and how to ignore external DTD reference?</A></LI><LI><A href="#faq-29">Why do I get segmentation fault when running on Redhat Linux?</A></LI><LI><A href="#faq-30">Why does the XML data generated by the DOMWriter does not match my original XML input?</A></LI><LI><A href="#faq-31">Why does my application crash when deleting the parser after releasing a document?</A></LI><LI><A href="#faq-32">Why do we have two versions of some XMLString methods (one with memory manager and one without)?</A></LI></UL></FONT></TD></TR></TABLE><BR><BR><A name="faq-1"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B> Does Xerces-C++ support Schema?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Yes. The Xerces-C++ 2.8.0 contains an implementation
of the W3C XML Schema Language, a recommendation of the Worldwide Web Consortium
available in three parts:
<A href="http://www.w3.org/TR/xmlschema-0/">XML Schema: Primer</A> and
<A href="http://www.w3.org/TR/xmlschema-1/">XML Schema: Structures</A> and
<A href="http://www.w3.org/TR/xmlschema-2/">XML Schema: Datatypes</A>.
We consider this implementation complete. See
<A href="schema.html#limitation">the Schema page</A> for limitations.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-2"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B> Why Xerces-C++ does not support this particular Schema feature?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The Xerces-C++ 2.8.0 contains an implementation
of the W3C XML Schema Language, a recommendation of the Worldwide Web Consortium
available in three parts:
<A href="http://www.w3.org/TR/xmlschema-0/">XML Schema: Primer</A> and
<A href="http://www.w3.org/TR/xmlschema-1/">XML Schema: Structures</A> and
<A href="http://www.w3.org/TR/xmlschema-2/">XML Schema: Datatypes</A>.
We consider this implementation complete. See
<A href="schema.html#limitation">the Schema page</A> for limitations.</P>
<P>If you find any Schema feature which is specified in the W3C XML Schema Language
Recommendation does not work with Xerces-C++ 2.8.0, we encourage
the submission of bugs as described in
<A href="bug-report.html">Bug Reporting</A> page.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-3"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does my application crash when instantiating the parser?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>In order to work with the Xerces-C++ parser, you have to first
initialize the XML subsystem. The most common mistake is to forget this
initialization. Before you make any calls to Xerces-C++ APIs, you must
call XMLPlatformUtils::Initialize(): </P>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
try {
XMLPlatformUtils::Initialize();
}
catch (const XMLException&amp; toCatch) {
// Do your failure processing here
}</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
<P>This initializes the Xerces system and sets its internal
variables. Note that you must the include <CODE><FONT face="courier, monospaced">xercesc/util/PlatformUtils.hpp</FONT></CODE> file for this to work.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-4"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Is it OK to call the XMLPlatformUtils::Initialize/Terminate pair of routines multiple times in one program?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Yes. Since Xerces-C++ 1.5.2, the code has been enhanced so that
calling XMLPlatformUtils::Initialize/Terminate pair of routines
multiple times in one process is now allowed.
</P>
<P>But the application needs to guarantee that only one thread has entered either the
method XMLPlatformUtils::Initialize() or the method XMLPlatformUtils::Terminate() at any
one time.</P>
<P>If you are calling XMLPlatformUtils::Initialize() a number of times, and then follow with
XMLPlatformUtils::Terminate() the same number of times, only the first XMLPlatformUtils::Initialize()
will do the initialization, and only the last XMLPlatformUtils::Terminate() will clean up
the memory. The other calls are ignored.
</P>
<P>To ensure all the memory held by the parser are freed, the number of XMLPlatformUtils::Terminate() calls
should match the number of XMLPlatformUtils::Initialize() calls.
</P>
<P>
Consider the following code snippets (for illustration simplicity the following
sample code is not coded in try/catch clause):
</P>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
// The XMLPlatformUtils::Initialize/Terminate calls are paired.
{
// Initialize the parser
XMLPlatformUtils::Initialize();
SAXParser* parser = new SAXParser;
parser-&gt;parse(xmlFile);
delete parser;
// Free all memory that was being held by the parser
XMLPlatformUtils::Terminate();
// Initialize the parser
XMLPlatformUtils::Initialize();
parser = new SAXParser;
parser-&gt;parse(xmlFile);
delete parser;
// Free all memory that was being held by the parser
XMLPlatformUtils::Terminate();
}
</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
// calls XMLPlatformUtils::Initialize() three times
// then calls XMLPlatformUtils::Terminate() numerous times
{
// Initialize the parser
XMLPlatformUtils::Initialize();
// The next two calls are no-op
XMLPlatformUtils::Initialize();
XMLPlatformUtils::Initialize();
SAXParser* parser = new SAXParser;
parser-&gt;parse(xmlFile);
delete parser;
// The first two XMLPlatformUtils::Terminate() calls are no-op
XMLPlatformUtils::Terminate();
XMLPlatformUtils::Terminate();
// This third XMLPlatformUtils::Terminate() will free all memory that was being held by the parser
XMLPlatformUtils::Terminate();
// This extra fourth XMLPlatformUtils::Terminate() call is no-op.
// However calling XMLPlatformUtils::Terminate() without a matching XMLPlatformUtils::Initialize()
// is dangerous and should be avoided.
XMLPlatformUtils::Terminate();
}
</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</FONT></TD></TR></TABLE><BR><A name="faq-5"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does my application crash or hang if XMLPlatformUtils::Initialize()/Terminate() pair is called more than once?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Please make sure you are using the Xerces-C++ 1.5.2 or up.
</P>
<P>Earlier version of Xerces-C++ does not allow XMLPlatformUtils::Initialize()/Terminate()
pair to be called more than once or has a problem.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-6"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does my application crash after calling XMLPlatformUtils::Terminate()?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Please make sure the XMLPlatformUtils::Terminate() is the last Xerces-C++ function to be called
in your program. NO explicit nor implicit Xerces-C++ destructor (those local data that are
destructed when going out of scope) should be called after XMLPlatformUtils::Terminate().
</P>
<P>
For example consider the following code snippets which is incorrect
(for illustration simplicity the following sample code is not coded in try/catch clause):
</P>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
1: {
2: XMLPlatformUtils::Initialize();
3: DOMString c(&quot;hello&quot;);
4: XMLPlatformUtils::Terminate();
5: }
</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
<P>The DOMString object &quot;c&quot; is destructed when going out of scope at line 5 before the closing
brace. As a result, DOMString destructor is called at line 5 after
XMLPlatformUtils::Terminate() which is wrong. Correct code should be:
</P>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
1: {
2: XMLPlatformUtils::Initialize();
2a: {
3: DOMString c(&quot;hello&quot;);
3a: }
4: XMLPlatformUtils::Terminate();
5: }
</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
<P>The extra pair of braces (line 2a and 3a) ensures that all implicit destructors are called
before terminating Xerces-C++.</P>
<P>In addition the application also needs to guarantee that only one thread has entered either the
method XMLPlatformUtils::Initialize() or the method XMLPlatformUtils::Terminate() at any
one time.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-7"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>I'm suddenly getting segfaults with Xerces-C 2.3.0;
why might this be?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The introduction of pluggable memory management into
Xerces-C, one of the main features of 2.3.0, means that
application writers have to be more conscious about
destructors being invoked implicitly after a call to
XMLPlatformUtils::Terminate(). For example, the
following code is guaranteed to produce a segmentation
fault under Xerces-C 2.3.0, while it happened to work
under previous versions (in fact, this was how our
SAXPrint sample was formerly written;
try-catch blocks removed for brevity):
</P>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
void myParsingFunction()
{
XMLPlatformUtils::Initialize();
SAXParser parser;
//parser.various method calls
XMLPlatformUtils::Terminate();
} // seg fault here!
</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
<P>The reason this will produce a segmentation fault is
that any dynamic memory the SAXParser (or any other of
Xerces's parsers) needs to allocate is now allocated
by default by a static object owned by XMLPlatformUtils.
When the XMLPlatformUtils::Terminate() call is made, this
object is destroyed--and, consequently, so are all the
objects that it directly created. This includes all the
objects dynamically allocated by the SAXParser. When the
parser object goes out of scope, its destructor is
invoked, and this attempts to destroy all the objects
that it created--which have of course just been destroyed
by the static MemoryManager in XMLPlatformUtils.
</P>
<P>
To avoid this, one must either explicitly scope the
parser object inside calls to
XMLPlatformUtils::Initialize() and
XMLPlatformUtils::Terminate(), or dynamically allocate
the parser object and destroy it explicitly before the
call to XMLPlatformUtils::Terminate() is made.
</P>
<P>Another way of producing segmentation faults--that again,
unfortunately, was employed by some of our
samples--is to have calls to XMLPlatformUtils::Terminate()
in a catch block that catches any of Xerces's exceptions.
Since the destructor of the exception will implicitly be
invoked upon exit from the catch block, and since some of
the exceptions' destructors call on Xerces's
default memory manager to destroy dynamically-allocated
objects, their destruction will provoke a segmentation
fault even if a return statement is placed in the catch
block since the default memory manager will no longer exist.
This practice is now avoided in all our samples.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-8"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Is Xerces-C++ thread-safe?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>This is not a question that has a simple yes/no answer. Here are the
rules for using Xerces-C++ in a multi-threaded environment:</P>
<P>Within an address space, an instance of the parser may be used without
restriction from a single thread, or an instance of the parser can be accessed
from multiple threads, provided the application guarantees that only one thread
has entered a method of the parser at any one time.</P>
<P>When two or more parser instances exist in a process, the instances can
be used concurrently, without external synchronization. That is, in an
application containing two parsers and two threads, one parser can be running
within the first thread concurrently with the second parser running within the
second thread.</P>
<P>The same rules apply to Xerces-C++ DOM documents. Multiple document
instances may be concurrently accessed from different threads, but any given
document instance can only be accessed by one thread at a time.</P>
<P>DOMStrings allow multiple concurrent readers. All DOMString const
methods are thread safe, and can be concurrently entered by multiple threads.
Non-const DOMString methods, such as <CODE><FONT face="courier, monospaced">appendData()</FONT></CODE>, are not thread safe and the application must guarantee that no other
methods (including const methods) are executed concurrently with them.</P>
<P>The application also needs to guarantee that only one thread has entered either the
method XMLPlatformUtils::Initialize() or the method XMLPlatformUtils::Terminate() at any
one time.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-9"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>I am seeing memory leaks in Xerces-C++. Are they real?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The Xerces-C++ library allocates and caches some commonly reused
items. The storage for these may be reported as memory leaks by some heap
analysis tools; to avoid the problem, call the function <CODE><FONT face="courier, monospaced">XMLPlatformUtils::Terminate()</FONT></CODE> before your application exits. This will free all memory that was being
held by the library.</P>
<P>For most applications, the use of <CODE><FONT face="courier, monospaced">Terminate()</FONT></CODE> is optional. The system will recover all memory when the application
process shuts down. The exception to this is the use of Xerces-C++ from DLLs
that will be repeatedly loaded and unloaded from within the same process. To
avoid memory leaks with this kind of use, <CODE><FONT face="courier, monospaced">Terminate()</FONT></CODE> must be called before unloading the Xerces-C++ library</P>
<P>To ensure all the memory held by the parser are freed, the number of XMLPlatformUtils::Terminate() calls
should match the number of XMLPlatformUtils::Initialize() calls.
</P>
<P>If you are using XML4C where ICU is used, you may call ICU function u_cleanup() to clean up
ICU static data. Please see <A href="http://icu-project.org/">ICU documentation</A>
for details.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-10"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>I find memory leaks in Xerces-C++. How do I eliminate it?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The &quot;leaks&quot; that are reported through a leak-detector or heap-analysis
tools aren't really leaks in most application, in that the memory usage does
not grow over time as the XML parser is used and re-used.</P>
<P>What you are seeing as leaks are actually lazily evaluated data
allocated into static variables. This data gets released when the application
ends. You can make a call to <CODE><FONT face="courier, monospaced">XMLPlatformUtil::terminate()</FONT></CODE> to release all the lazily allocated variables before you exit your
program.</P>
<P>To ensure all the memory held by the parser are freed, the number of XMLPlatformUtils::Terminate() calls
should match the number of XMLPlatformUtils::Initialize() calls.
</P>
<P>If you are using XML4C where ICU is used, you may call ICU function u_cleanup() to clean up
ICU static data. Please see <A href="http://icu-project.org/">ICU documentation</A>
for details.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-11"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Is there a function that I have totally missed that creates
an XML file from a DTD, (obviously with the values missing, a skeleton, as it
were)?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>No. This is not supported.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-12"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Can I use Xerces-C++ to perform &quot;write validation&quot; (which is having an
appropriate Grammar and being able to add elements to the DOM whilst validating
against the grammar)?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>No. This is not supported.</P>
<P>The best you can do for now is to create the DOM document, write it back
as XML and re-parse it.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-13"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Is there a facility in Xerces-C++ to validate the data contained in a
DOM tree? That is, without saving and re-parsing the source document?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>No. The best option for now is to generate XML source from the DOM and feed that back
into the parser.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-14"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>How to write out a DOM tree into a string or an XML file?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Please make sure you are using Xerces-C++ 2.8.0 or up.</P>
<P>You can use
the DOMWriter::writeToString, or DOMWriter::writeNode to serialize a DOM tree.
Please refer to the sample DOMPrint or the API documentation for more details of
DOMWriter.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-15"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does DOMNode::cloneNode() not clone the pointer assigned to a DOMNode via DOMNode::setUserData()?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Xerces-C++ supports the DOMNode::userData specified
in <A href="http://www.w3.org/TR/2003/WD-DOM-Level-3-Core-20030226/DOM3-Core.html#core-ID-3A0ED0A4">
the DOM level 3 Node interface</A>. As
is made clear in the description of the behaviour of
<CODE><FONT face="courier, monospaced">cloneNode()</FONT></CODE>, userData that has been set on the
Node is not cloned. Thus, if the userData is to be copied
to the new Node, this copy must be effected manually.
Note further that the operation of <CODE><FONT face="courier, monospaced">importNode()</FONT></CODE>
is specified similarly.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-16"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>How are entity reference nodes handled in DOM?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>If you are using the native DOM classes, the function <CODE><FONT face="courier, monospaced">setCreateEntityReferenceNodes</FONT></CODE>
controls how entities appear in the DOM tree. When
setCreateEntityReferenceNodes is set to true (the default), an occurrence of an
entity reference in the XML document will be represented by a subtree with an
EntityReference node at the root whose children represent the entity expansion.
Entity expansion will be a DOM tree representing the structure of the entity
expansion, not a text node containing the entity expansion as text.</P>
<P>If setCreateEntityReferenceNodes is false, an entity reference in the XML
document is represented by only the nodes that represent the entity expansion.
The DOM tree will not contain any entityReference nodes.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-17"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>What kinds of URLs are currently supported in Xerces-C++?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The <CODE><FONT face="courier, monospaced">XMLURL</FONT></CODE> class provides for limited URL support. It understands the <CODE><FONT face="courier, monospaced">file://, http://</FONT></CODE>, and <CODE><FONT face="courier, monospaced">ftp://</FONT></CODE> URL types, and is capable or parsing them into their constituent
components, and normalizing them. It also supports the commonly required action
of conglomerating a base and relative URL into a single URL. In other words, it
performs the limited set of functions required by an XML parser.</P>
<P>Another thing that URLs commonly do are to create an input stream that
provides access to the entity referenced. The parser, as shipped, only supports
this functionality on URLs in the form <CODE><FONT face="courier, monospaced">file:///</FONT></CODE> and <CODE><FONT face="courier, monospaced">file://localhost/</FONT></CODE>, i.e. only when the URL refers to a local file.</P>
<P>You may enable support for HTTP and FTP URLs by implementing and
installing a NetAccessor object. When a NetAccessor object is installed, the
URL class will use it to create input streams for the remote entities referred
to by such URLs.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-18"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>How can I add support for URLs with HTTP/FTP protocols?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Support for the http: protocol is now included by default on all
platforms.</P>
<P>To address the need to make remote connections to resources specified
using additional protocols, ftp for example, Xerces-C++ provides the <CODE><FONT face="courier, monospaced">NetAccessor</FONT></CODE> interface. The header file is <CODE><FONT face="courier, monospaced">src/xercesc/util/XMLNetAccessor.hpp</FONT></CODE>. This interface allows you to plug in your own implementation of URL
networking code into the Xerces-C++ parser.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-19"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Can I use Xerces-C++ to parse HTML?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Yes, but only if the HTML follows the rules given in the
<A href="http://www.w3.org/TR/REC-xml">XML specification</A>. Most HTML,
however, does not follow the XML rules, and will generate XML well-formedness
errors.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-20"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>I keep getting an error: &quot;invalid UTF-8 character&quot;. What's wrong?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Most commonly, the XML <CODE><FONT face="courier, monospaced">encoding =</FONT></CODE> declaration is either incorrect or missing. Without a declaration, XML
defaults to the use utf-8 character encoding, which is not compatible with the
default text file encoding on most systems.</P>
<P>The XML declaration should look something like this:</P>
<P><CODE><FONT face="courier, monospaced">&lt;?xml version=&quot;1.0&quot; encoding=&quot;iso-8859-1&quot;?&gt;</FONT></CODE></P>
<P>Make sure to specify the encoding that is actually used by file. The
encoding for &quot;plain&quot; text files depends both on the operating system and the
locale (country and language) in use.</P>
<P>Another common source of problems is that some characters are not
allowed in XML documents, according to the XML spec. Typical disallowed
characters are control characters, even if you escape them using the Character
Reference form. See the <A href="http://www.w3.org/TR/REC-xml#charsets">XML
spec</A>, sections 2.2 and 4.1 for details. If the parser is generating an <CODE><FONT face="courier, monospaced">Invalid character (Unicode: 0x???)</FONT></CODE> error, it is very likely that there's a character in there that you
can't see. You can generally use a UNIX command like &quot;od -hc&quot; to find it.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-21"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>What encodings are supported by Xerces-C / XML4C?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Xerces-C has intrinsic support for ASCII, UTF-8, UTF-16 (Big/Small
Endian), UCS4 (Big/Small Endian), EBCDIC code pages IBM037, IBM1047 and IBM1140
encodings, ISO-8859-1 (aka Latin1) and Windows-1252. This means that it can
parse input XML files in these above mentioned encodings.</P>
<P>XML4C -- the version of Xerces-C available from IBM -- combines Xerces-C
and <A href="http://icu-project.org/">
International Components for Unicode (ICU)</A> and
extends the encoding support to over 100 different encodings that are allowed
by ICU. In particular, all the encodings registered with the
<A href="http://www.iana.org/assignments/character-sets">
Internet Assigned Numbers Authority (IANA) </A> are supported in XML4C.</P>
<P>Some implementations or ports of Xerces-C provide support for
additional encodings. The exact set will depend on the supplier of the parser
and on the character set transcoding services in use.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-22"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>What character encoding should I use when creating XML documents?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The best choice in most cases is either utf-8 or utf-16. Advantages of
these encodings include:</P>
<UL>
<LI>The best portability. These encodings are more widely supported by
XML processors than any others, meaning that your documents will have the best
possible chance of being read correctly, no matter where they end up.</LI>
<LI>Full international character support. Both utf-8 and utf-16 cover the
full Unicode character set, which includes all of the characters from all major
national, international and industry character sets.</LI>
<LI>Efficient. utf-8 has the smaller storage requirements for documents
that are primarily composed of characters from the Latin alphabet. utf-16 is
more efficient for encoding Asian languages. But both encodings cover all
languages without loss.</LI>
</UL>
<P>The only drawback of utf-8 or utf-16 is that they are not the native
text file format for most systems, meaning that common text file editors and
viewers can not be directly used.</P>
<P>A second choice of encoding would be any of the others listed in the
table above. This works best when the xml encoding is the same as the default
system encoding on the machine where the XML document is being prepared,
because the document will then display correctly as a plain text file. For UNIX
systems in countries speaking Western European languages, the encoding will
usually be iso-8859-1.</P>
<P>The versions of Xerces distributed by IBM, both C and Java (known
respectively as XML4C and XML4J), include all of the encodings listed in the
above table, on all platforms.</P>
<P>A word of caution for Windows users: The default character set on
Windows systems is windows-1252, not iso-8859-1. While Xerces-C++ does
recognize this Windows encoding, it is a poor choice for portable XML data
because it is not widely recognized by other XML processing tools. If you are
using a Windows-based editing tool to generate XML, check which character set
it generates, and make sure that the resulting XML specifies the correct name
in the <CODE><FONT face="courier, monospaced">encoding=&quot;...&quot;</FONT></CODE> declaration.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-23"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Is EBCDIC supported?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Yes, Xerces-C++ supports EBCDIC with the ibm1140, ibm037 and ibm1047 encodings.
When creating EBCDIC encoded XML data, the preferred encoding is ibm1140. The ibm037 encoding,
and its alternate name, ebcdic-cp-us, is almost the same as ibm1140, but
it lacks the Euro symbol.</P>
<P>These three encodings, ibm1140, ibm037 and ibm1047, are available on both
Xerces-C and IBM XML4C, on all platforms.</P>
<P>On IBM System 390, XML4C also supports three alternative forms,
ibm037-s390, ibm1140-s390, and ibm1047-s390. These are similar to the base ibm037, ibm1140, and ibm1047
encodings, but with alternate mappings of the EBCDIC new-line character, which
allows them to appear as normal text files on System 390. These encodings are
not supported on other platforms, and should not be used for portable data.</P>
<P>XML4C on System 390 and AS/400 also provides additional EBCDIC
encodings, including those for the character sets of different countries. The
exact set supported will be platform dependent, and these encodings are not
recommended for portable XML data.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-24"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does deleting a transcoded string result in assertion on windows?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>Both your application program and the Xerces-C++ DLL must use the same *DLL* version of the
runtime library. If either statically links to the runtime library, the
problem will still occur.</P>
<P>For example, for a Win32/VC6 build, the runtime library build setting MUST
be &quot;Multithreaded DLL&quot; for release builds and &quot;Debug Multithreaded DLL&quot; for
debug builds.</P>
<P>Or for example for a Win32/BCB6 build, application need to switch to Multithreaded
runtime to avoid such memory access violation.</P>
<P>To bypass such problem, instead of calling operator delete[] directly, you can use the
provided function XMLString::release to delete any string that was allocated by the parser.
This will ensure the string is allocated and deleted by the same DLL and such assertion
problem should be resolved.</P>
</FONT></TD></TR></TABLE><BR><A name="faq-25"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>How do I transcode to/from something besides the local code page?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>XMLString::transcode() will transcode from XMLCh to the local code page, and
other APIs which take a char* assume that the source text is in the local
code page. If this is not true, you must transcode the text yourself. You
can do this using local transcoding support on your OS, such as Iconv on
Unix or IBM's ICU package. However, if your transcoding needs are simple,
you can achieve some better portability by using the Xerces-C++ parser's
transcoder wrappers. You get a transcoder like this:
</P>
<UL>
<LI>
Call XMLPlatformUtils::fgTransServer-&gt;MakeNewTranscoderFor() and provide
the name of the encoding you wish to create a transcoder for. This will
return a transcoder to you, which you own and must delete when you are
through with it.
NOTE: You must provide a maximum block size that you will pass to the transcoder
at one time, and you must pass blocks of characters of this count or smaller when
you do your transcoding. The reason for this is that this is really an
internal API and is used by the parser itself to do transcoding. The parser
always does transcoding in known block sizes, and this allows transcoders to
be much more efficient for internal use since it knows the max size it will
ever have to deal with and can set itself up for that internally. In
general, you should stick to block sizes in the 4 to 64K range.
</LI>
<LI>
The returned transcoder is something derived from XMLTranscoder, so they
are all returned to you via that interface.
</LI>
<LI>
This object is really just a wrapper around the underlying transcoding
system actually in use by your version of Xerces, and does whatever is
necessary to handle differences between the XMLCh representation and the
representation used by that underlying transcoding system.
</LI>
<LI>
The transcoder object has two primary APIs, transcodeFrom() and
transcodeTo(). These transcode between the XMLCh format and the encoding you
indicated.
</LI>
<LI>
These APIs will transcode as much of the source data as will fit into the
outgoing buffer you provide. They will tell you how much of the source they
ate and how much of the target they filled. You can use this information to
continue the process until all source is consumed.
</LI>
<LI>
char* data is always dealt with in terms of bytes, and XMLCh data is
always dealt with in terms of characters. Don't mix up which you are dealing
with or you will not get the correct results, since many encodings don't
have a one to one relationship of characters to bytes.
</LI>
<LI>
When transcoding from XMLCh to the target encoding, the transcodeTo()
method provides an 'unrepresentable flag' parameter, which tells the
transcoder how to deal with an XMLCh code point that cannot be converted
legally to the target encoding, which can easily happen since XMLCh is
Unicode and can represent thousands of code points. The options are to use a
default replacement character (which the underlying transcoding service will
choose, and which is guaranteed to be legal for the target encoding), or to
throw an exception.
</LI>
</UL>
<P>Here is an example:</P>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
// create an XMLTranscoder that is able to transcode between Unicode and Big5
// ASSUMPTION: assumes your underlying transcoding utility supports this encoding Big5
XMLTranscoder* t =
XMLPlatformUtils::fgTransService-&gt;makeNewTranscoderFor(&quot;Big5&quot;, failReason, 16*1024, MemoryManager);
// source string is in Unicode, wanna to transcode to Big5
t-&gt;transcodeTo(source_unicode, length, result_Big5, length, charsEaten, XMLTranscoder::UnRep_Throw );
// source string in Big5, wanna to transcode to Unicode
t-&gt;transcodeFrom(source_Big5, length, result_unicode, length, bytesEaten, (unsigned char*)charSz);
</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</FONT></TD></TR></TABLE><BR><A name="faq-26"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does setProperty not work?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The function <CODE><FONT face="courier, monospaced">SAX2XMLReader::setProperty(const XMLCh* const name, void* value)</FONT></CODE>
and <CODE><FONT face="courier, monospaced">DOMBuilder::setProperty(const XMLCh* const name, void* value)</FONT></CODE>
takes a void pointer for the property value. Application is required to initialize this void pointer
to a correct type. See <A href="program-sax2.html#SAX2Properties">SAX2 Programming Guide</A>
and <A href="program-dom.html#DOMBuilderProperties">DOM Programming Guide</A>
to learn exactly what type of property value that each property expects for processing.
Passing a void pointer that was initialized with a wrong type will lead to unexpected result.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-27"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does getProperty not work?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>The function <CODE><FONT face="courier, monospaced">void* SAX2XMLReader::getProperty(const XMLCh* const name)</FONT></CODE>
and <CODE><FONT face="courier, monospaced">void* DOMBuilder::getProperty(const XMLCh* const name)</FONT></CODE>
returns a void pointer for the property value. See
<A href="program-sax2.html#SAX2Properties">SAX2 Programming Guide</A> and
exactly what type of object each property returns.
</P>
<P>The parser owns the returned pointer. The memory allocated for
the returned pointer will be destroyed when the parser is deleted.
To ensure accessibility of the returned information after the parser
is deleted, callers need to copy and store the returned information
somewhere else; otherwise you may get unexpected result. Since the returned
pointer is a generic void pointer, see
<A href="program-sax2.html#SAX2Properties">SAX2 Programming Guide</A> and
<A href="program-dom.html#DOMBuilderProperties">DOM Programming Guide</A> to learn
exactly what type of property value each property returns for replication.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-28"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does the parser still try to locate the DTD even validation is turned off
and how to ignore external DTD reference?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>When DTD is referenced, the parser will try to read it, because DTDs can
provide a lot more information than just validation. It defines entities and
notations, external unparsed entities, default attributes, character
entities, etc... So it will always try to read it if present, even if
validation is turned off.
</P>
<P>To ignore the DTD, with Xerces-C++ 2.8.0 or up, you can call
<CODE><FONT face="courier, monospaced">setLoadExternalDTD(false)</FONT></CODE> (or
<CODE><FONT face="courier, monospaced">setFeature(XMLUni::fgXercesLoadExternalDTD, false)</FONT></CODE>
to disable the loading of external DTD. The parser will then ignore
any external DTD completely if the validationScheme is set to Val_Never.
</P>
<P>Note: This flag is ignored if the validationScheme is set to Val_Always or Val_Auto.
</P>
<P>To ignore the DTD in earlier version of Xerces-C++, the
only way to get around this is to install an EntityResolver
(see the Redirect sample for an example of how this is done), and reset the
DTD file to &quot;&quot;.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-29"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why do I get segmentation fault when running on Redhat Linux?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>There were some problems with Redhat Linux 7.x with C++ exception handling across shared
libraries. More details can be found
<A href="http://rhn.redhat.com/errata/RHBA-2002-055.html">here</A>.
Please try to upgrade your Redhat Linux gcc to the latest patch level and see if it helps.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-30"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does the XML data generated by the DOMWriter does not match my original XML input?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>If you parse an xml document using XercesDOMParser or DOMBuilder and pass such DOMNode
to DOMWriter for serialization, you may not get something that is exactly the same
as the original XML data. The parser may have done normalization, end of line conversion,
or has expanded the entity reference as per the XML 1.0 spec, 4.4 XML Processor Treatment of
Entities and References. From DOMWriter perspective, it does not know what the original
string was, all it sees is a processed DOMNode generated by the parser.
But since the DOMWriter is supposed to generate something that is parsable if sent
back to the parser, it will not print the DOMNode node value as is. The DOMWriter
may do some &quot;touch up&quot; to the output data for it to be parsable.</P>
<P>See <A href="program-dom.html#DOMWriterEntityRef">How does DOMWriter handle built-in entity
Reference in node value?</A> to understand further how DOMWriter touches up the entity reference.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-31"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why does my application crash when deleting the parser after releasing a document?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>In most cases, the parser handles deleting documents when the parser gets deleted. However, if an application
needs to release a document, it shall adopt the document before releasing it, so that the parser
knows that the ownership of this particular document is transfered to the application and will not
try to delete it once the parser gets deleted.
</P>
<DIV align="left"><TABLE border="0" cellpadding="0" cellspacing="4" width="464"><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff" width="462"><FONT size="-1"><PRE>
XercesDOMParser *parser = new XercesDOMParser;
...
try
{
parser-&gt;parse(gXmlFile);
}
catch ()
{
...
}
DOMNode *doc = parser-&gt;getDocument();
...
parser-&gt;adoptDocument();
doc-&gt;release();
...
delete parser;
</PRE></FONT></TD><TD bgcolor="#0086b2" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" height="1" width="462"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="462"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
<P>The alternative to release document is to call parser's resetDocumentPool(), which releases
all the documents parsed.
</P>
</FONT></TD></TR></TABLE><BR><A name="faq-32"><!--anchor--></A><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="ffffff" colspan="2" width="494"><TABLE border="0" cellpadding="0" cellspacing="0" width="494"><TR><TD bgcolor="#039acc" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#039acc" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#039acc" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#0086b2" width="492"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="2" hspace="0" src="resources/void.gif" vspace="0" width="2"><B>Why do we have two versions of some XMLString methods (one with memory manager and one without)?</B></FONT></TD><TD bgcolor="#017299" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#0086b2" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#017299" height="1" width="492"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="492"></TD><TD bgcolor="#017299" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></TD></TR><TR><TD width="10">&nbsp;</TD><TD width="484"><FONT color="#000000" face="arial,helvetica,sanserif">
<P>With the introduction of the configurable memory manager, we didn't want to break users by
changing the signature of the existing methods (for example, transcode and replicate). Also,
we did not want to provide a default memory
manager as it would introduce a side effect with users experiencing some strange core dumps.
The latter will occur when the scope of the string allocated is beyond that of
XMLPlatformUtils::Terminate (i.e. a string is allocated using the default memory manager
which is deleted when XMLPlatformUtils::Terminate is called, but the allocated string is
deleted later). We plan to deprecate the methods without a memory manager in a later release.
</P>
</FONT></TD></TR></TABLE><BR></TD></TR></TABLE></TD></TR></TABLE><BR><TABLE border="0" cellpadding="0" cellspacing="0" width="620"><TR><TD bgcolor="#0086b2"><IMG height="1" src="images/dot.gif" width="1"></TD></TR><TR><TD align="center"><FONT color="#0086b2" size="-1"><I>
Copyright &copy; 1999-2007 The Apache Software Foundation.
All Rights Reserved.
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