/**
* Construct an XML tree from a file.
*
* <code>
* $tree= Tree::fromFile(new File('foo.xml'));
* </code>
*
* @param io.File file
* @param string c default __CLASS__ class name
* @return xml.Tree
* @throws xml.XMLFormatException in case of a parser error
* @throws io.IOException in case reading the file fails
*/
public static function fromFile($file, $c = __CLASS__)
{
$parser = new XMLParser();
$tree = new $c();
$parser->setCallback($tree);
$parser->parse(FileUtil::getContents($file));
// Fetch actual encoding from parser
$tree->setEncoding($parser->getEncoding());
delete($parser);
return $tree;
}