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// file : examples/cxx/tree/streaming/driver.cxx
// author : Boris Kolpackov <boris@codesynthesis.com>
// copyright : not copyrighted - public domain
#include <iostream>
#include <fstream>
#include <xercesc/dom/DOM.hpp>
#include <xsd/cxx/xml/string.hxx> // xml::string
#include "parser.hxx"
#include "serializer.hxx"
#include "position.hxx"
using namespace std;
using namespace xercesc;
static void
measure_position (unsigned int n, float& lat, float& lon);
int
main (int argc, char* argv[])
{
if (argc != 2)
{
cerr << "usage: " << argv[0] << " position.xml" << endl;
return 1;
}
int r (0);
// We need to initialize the Xerces-C++ runtime because we are doing
// the XML-to-DOM parsing ourselves.
//
xercesc::XMLPlatformUtils::Initialize ();
try
{
using namespace op;
namespace xml = xsd::cxx::xml;
// Parse.
//
ifstream ifs;
ifs.exceptions (ifstream::badbit | ifstream::failbit);
ifs.open (argv[1]);
parser p;
// The first document we get is the "carcase" of the complete document.
// That is, the root element with all the attributes but without any
// content. We may need it to get to the attributes in the root element.
//
// There are two ways this can be done. The easiest approach is to
// instantiate the root element's type (object in our case). This
// will only work if all the content in the root element is optional.
// Alternatively, we can manually look up attributes that we are
// interested in and instantiate the corresponding type. The following
// fragment shows how to use the second approach.
//
xml_schema::dom::auto_ptr<DOMDocument> doc (p.start (ifs, argv[1], true));
// Find the id attribute.
//
DOMAttr* id_attr (
doc->getDocumentElement ()->getAttributeNode (
xml::string ("id").c_str ()));
// Use the type and traits aliases from the object model.
//
object::id_type id (object::id_traits::create (*id_attr, 0, 0));
cerr << "id: " << id << endl;
// The next chunk we get is the header element.
//
doc = p.next ();
header hdr (*doc->getDocumentElement ());
cerr << "name: " << hdr.name () << endl
<< "type: " << hdr.type () << endl;
// The rest is position elements.
//
for (doc = p.next (); doc.get () != 0; doc = p.next ())
{
position p (*doc->getDocumentElement ());
cerr << "lat: " << p.lat () << " lon: " << p.lon () << endl;
}
// Serialize.
//
ofstream ofs;
ofs.exceptions (ios_base::badbit | ios_base::failbit);
ofs.open ("out.xml");
serializer s;
// With this approach we manually write the XML declaration, opening
// and closing root element tags, as well as any attributes in the
// root element.
//
ofs << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" << endl
<< "<op:object xmlns:op=\"http://www.codesynthesis.com/op\"" << endl
<< " xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"" << endl
<< " xsi:schemaLocation=\"http://www.codesynthesis.com/op " <<
"position.xsd\"" << endl
<< " id=\"" << 123 << "\">" << endl;
s.start (ofs);
// Serialize the header.
//
header h ("Lion's Head", "rock");
s.next ("header", h);
// Serialize position elements, one at a time.
//
for (unsigned short i (0); i < 8; i++)
{
float lat, lon;
measure_position (i, lat, lon);
position p (lat, lon);
s.next ("position", p);
}
// Close the root element.
//
ofs << endl
<< "</op:object>" << endl;
}
catch (const xml_schema::exception& e)
{
cerr << e << endl;
r = 1;
}
catch (const ios_base::failure&)
{
cerr << "io failure" << endl;
r = 1;
}
xercesc::XMLPlatformUtils::Terminate ();
return r;
}
// Position measurement instrument interface.
//
struct measurements
{
float lat;
float lon;
};
measurements test_measurements [8] =
{
{-33.8569F, 18.5083F},
{-33.8568F, 18.5083F},
{-33.8568F, 18.5082F},
{-33.8570F, 18.5083F},
{-33.8569F, 18.5084F},
{-33.8570F, 18.5084F},
{-33.8570F, 18.5082F},
{-33.8569F, 18.5082F}
};
static void
measure_position (unsigned int n, float& lat, float& lon)
{
// Call the instrument to measure the position.
//
lat = test_measurements[n].lat;
lon = test_measurements[n].lon;
}
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