關于項目自動化測試架構的改良計劃 - 解析XInclude標記

因為在test_suite.xml中，我們多處使用了XInclude標記，他們會被申明在一個叫"http://www.w3.org/2001/XInclude" 的名字空間中，并且引入部分用xi:include來聲明，我們這個類的作用就是把這些所有的<xi:include>的部分，都用被引入的文件插入和替換掉。

/**
 * This class will handle converting a xinclude+xpointer marked xml file to a normal xml file
 * Because of the shortage of the current jdk ,it only support the xPointer with element instead of NCName
 *@author cwang58
 *@created date: Jun 10, 2013
 */
public class XIncludeConverter {
                                                                                                                                                  
    /**
     * this method will handle change the XInclude+XPointer marked xml as normal xml
     * @param origialXML the original xml which has the xInclude feature
     * @return the parsedXML without the xInclude feature
     */
    public static String convertXInclude2NormalXML(String originalXML)
            throws SAXException,ParserConfigurationException,TransformerConfigurationException,IOException,TransformerException{
          DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
          //open up the namespace aware so that it can recognize the "xi" namespace
          factory.setNamespaceAware(true);
          //let this SAXParser support XInclude
          factory.setXIncludeAware(true);
          //factory.setValidating(true);
          //ignore all the comments added in the source document
          factory.setIgnoringComments(true);
          DocumentBuilder docBuilder = factory.newDocumentBuilder();
          Document doc = docBuilder.parse(new InputSource(new ByteArrayInputStream(originalXML.getBytes("utf-8"))));
          Transformer transformer = TransformerFactory.newInstance().newTransformer();
          //format the output xml string so it support indent and more readable
          transformer.setOutputProperty(OutputKeys.INDENT, "yes");
          //initialize StreamResult with File object to save to file
          StreamResult result = new StreamResult(new StringWriter());
          DOMSource source = new DOMSource(doc);
          transformer.transform(source, result);
          return result.getWriter().toString();
        }
                                                                                                                                                 

這里講一個小插曲，其實，W3C中，XInclude經常和Xpointer聯合起來應用的，xpointer可以幫助來定位目標文件的某個小片段而不是整個目標文件，定位方法可以用element(),或者xpointer()，如果element的話，可以用（/1/2/3)這種方式來定位DOM，或者基于 id，對應java的解析框架是xerce,但是非常不幸運的是，最新版本的xerce框架只支持element(/1/3/4/5)這種定位，而對于基于schema-id的方式，也就是某個element聲明了id的情況，它沒辦法定位，但是未來可能會支持這個功能。

http://xerces.apache.org/xerces2-j/faq-xinclude.html#faq-8

基于上述的局限性，我決定只采用xi:include來包含全部文件，然后局部調整的做法，并且繞過xpointer。

所以實現代碼如上所示，事實上從JDK 1.6開始，他已經提供了對XInclude的支持，內部是委托給xerce來實現的，這是對應架構圖的第3-4步驟。