protected function processSharedStringsItem($xmlReader, $sharedStringIndex, $escaper)
{
$node = $this->getSimpleXmlElementNodeFromXMLReader($xmlReader);
$node->registerXPathNamespace('ns', self::MAIN_NAMESPACE_FOR_SHARED_STRINGS_XML);
// removes nodes that should not be read, like the pronunciation of the Kanji characters
$cleanNode = $this->removeSuperfluousTextNodes($node);
// find all text nodes "t"; there can be multiple if the cell contains formatting
$textNodes = $cleanNode->xpath('//ns:t');
$textValue = $this->extractTextValueForNodes($textNodes);
$unescapedTextValue = $escaper->unescape($textValue);
$this->cachingStrategy->addStringForIndex($unescapedTextValue, $sharedStringIndex);
}