protected function getIdentifiers($schemaString)
{
$allTokens = '#<(.*)>#U';
$identifiers = '#\\W#';
$tmpArray = array();
preg_match_all($allTokens, $schemaString, $matches);
foreach ($matches[1] as $match) {
$tmpArray[] = preg_split($identifiers, $match, -1, PREG_SPLIT_NO_EMPTY);
}
$retArray = array();
foreach ($tmpArray as $matchGroup) {
if (is_array($matchGroup)) {
foreach ($matchGroup as $item) {
$retArray[] = $item;
}
} else {
$retArray[] = $matchGroup;
}
}
return $retArray;
}