Use of text() function when using xPath in dom4j
- by jlawless
I have inherited an application that parses xml using dom4j and xPath:
The xml being parsed is similar to the following:
<cache>
<content>
<transaction>
<page>
<widget name="PAGE_ID">WRK_REGISTRATION</widget>
<widget name="TRANS_DETAIL_ID">77145</widget>
<widget name="GRD_ERRORS" />
</page>
<page>
<widget name="PAGE_ID">WRK_REGISTRATION</widget>
<widget name="TRANS_DETAIL_ID">77147</widget>
<widget name="GRD_ERRORS" />
</page>
<page>
<widget name="PAGE_ID">WRK_PROCESSING</widget>
<widget name="TRANS_DETAIL_ID">77152</widget>
<widget name="GRD_ERRORS" />
</page>
</transaction>
</content>
</cache>
Individual Nodes are being searched using the following:
String xPathToGridErrorNode = "//cache/content/transaction/page/widget[@name='PAGE_ID'][text()='WRK_DNA_REGISTRATION']/../widget[@name='TRANS_DETAIL_ID'][text()='77147']/../widget[@name='GRD_ERRORS_TEMP']";
org.dom4j.Element root = null;
SAXReader reader = new SAXReader();
Document document = reader.read(new BufferedInputStream(new ByteArrayInputStream(xmlToParse.getBytes())));
root = document.getRootElement();
Node gridNode = root.selectSingleNode(xPathToGridErrorNode);
where xmlToParse is a String of xml similar to the excerpt provided above.
The code is trying to obtain the GRD_ERROR node for the page with the PAGE_ID and TRANS_DETAIL_ID provided in the xPath.
I am seeing an intermittent (~1-2%) failure (returned node is null) of this selectSingleNode request even though the requested node is in the xml being searched.
I know there are some gotchas associated with using text()= in xPath and was wondering if there was a better way to format the xPath string for this type of search.
