Xpath 2.0 如何在Java7中通过XPath使用JDOM2获取所有元素名？

我有一个如下所示的XML文件

<?xml version="1.0" encoding="UTF-8"?>
<Site>
  <Name>MySite</Name>
  <Groups>
      <Default></Default>
      <GroupA></GroupA>
  </Groups>
</Site>

public List<String> getGroupNames() {
    List<String> names = new ArrayList<String>();

    XPathExpression<Text> xpath = XPathFactory.instance().compile(
            "/Site/Groups/*/name()", Filters.text());

    List<Text> elements = xpath.evaluate(document);

    if (elements.size() > 0) {
        for (Text text : elements) {
            names.add(text.getText());
        }
        return names;
    }
    return null;
}

---

正确的语法是什么？我不理解这个异常。

您使用的XPathFactory实例似乎只支持XPath 1

class org.jaxen.saxpath.XPathSyntaxException: /Site/Groups/*/name(): 20: Expected node-type

在能够使用XPath2之前，需要加载支持XPath2的库。例如：撒克逊人：

import net.sf.saxon.om.NamespaceConstant;  


String objectModel = NamespaceConstant.OBJECT_MODEL_SAXON;  
System.setProperty("javax.xml.xpath.XPathFactory:"+objectModel, "net.sf.saxon.xpath.XPathFactoryImpl");