用XQilla根据XPATH解析XML

代码如下：
#include <iostream>
#include <xercesc/dom/DOM.hpp>
#include <xercesc/framework/StdOutFormatTarget.hpp>
#include <xercesc/framework/MemBufFormatTarget.hpp>
#include <xercesc/framework/MemBufInputSource.hpp>
#include <xercesc/parsers/XercesDOMParser.hpp>
#include <xercesc/framework/Wrapper4InputSource.hpp>
#include <xqilla/xqilla-dom3.hpp>

XERCES_CPP_NAMESPACE_USE;
using namespace std;

string xml_string =
"<corporation><node id='10000'>奥巴马</node><node id='10001'>student</node></corporation>";

DOMImplementation* xqillaImplementation = NULL;

void getpathvalue(DOMDocument* d)
{
        const char* expression = "data(/corporation/node/@id)";
        AutoRelease<DOMXPathNSResolver>
                resolver(d->createNSResolver(d->getDocumentElement()));
        AutoRelease<DOMXPathExpression>
                parsedExpression(d->createExpression(X(expression), resolver));
        AutoRelease<DOMXPathResult>
                Result(parsedExpression->evaluate(
                                        d,
                                        DOMXPathResult::ITERATOR_RESULT_TYPE, 0));
        if (Result->iterateNext())
        {
                AutoRelease<DOMLSSerializer>
                        serializer(xqillaImplementation->createLSSerializer());
                AutoRelease<DOMLSOutput>
                        output(xqillaImplementation->createLSOutput());

                MemBufFormatTarget* target = new MemBufFormatTarget();
                output->setByteStream(target);

                if(Result->isNode())
                {
                        cout << "Result: "<< flush;
                        serializer->write(Result->getNodeValue(), output);
                        cout<< target->getRawBuffer()<< endl;
                }
                else
                {
                        std::cout
                                << XMLString::transcode(Result->getStringValue())
                                << std::endl;
                }
        }
        else
        {
                std::cout<< "NULL"<< std::endl;
        }
}

int main(int argc, char *argv[])
{
        try {
                XQillaPlatformUtils::initialize();
        } catch (const XMLException& eXerces) {
                cerr << "Error during Xerces-C initialisation.\n"
                        << "Xerces exception message: "
                        << UTF8(eXerces.getMessage()) << endl;
                return 1;
        }

        try {
                xqillaImplementation =
                        DOMImplementationRegistry::getDOMImplementation(X("LS"));
                //part1: 解析新组建树的例子
                DOMDocument* doc = xqillaImplementation->createDocument(
                                0,
                                X("corporation"),
                                0);
                DOMElement* root_elem = doc->getDocumentElement();
                DOMElement* node = doc->createElement(X("node"));
                node->setTextContent(X("K L"));
                node->setAttribute(X("id"), X("10005"));
                root_elem->appendChild(node);
                getpathvalue( doc );
                //
                //part2: 解析内存字符串的例子
                AutoRelease<DOMLSParser> parser(
                                xqillaImplementation->createLSParser(
                                        DOMImplementationLS::MODE_SYNCHRONOUS, 0));
                parser->getDomConfig()->setParameter(XMLUni::fgDOMNamespaces, false);
                parser->getDomConfig()->setParameter(XMLUni::fgXercesSchema, false);
                parser->getDomConfig()->setParameter(XMLUni::fgDOMValidateIfSchema, false);

                MemBufInputSource* xml_mem = new MemBufInputSource(
                                (const XMLByte* )xml_string.c_str(),
                                strlen(xml_string.c_str()),
                                "xml",
                                false);
                DOMDocument* document =
                        parser->parse( new Wrapper4InputSource(xml_mem) );
                getpathvalue( document );
                //
        }
        catch(DOMException &e) {
                cerr << "DOMException: " << UTF8(e.getMessage()) << endl;
                return 1;
        }

        XQillaPlatformUtils::terminate();
        return 0;
}