Java XML 解析/查询

Question

我有这样的 XML 结构，当我使用 NodeList nList = doc.getElementsByTagName("stock");它返回我 3 只股票，2 个主要股票标签和一个在子股票下的股票。我只想获取上层的两个库存，而忽略所有在 substock 标签下的库存。

在 Java 中是否可以在 C# 中进行类似于 LINQ 查询的操作，比如仅返回名称等于“Sony”的元素。

谢谢!

<city>
   <stock>
     <name>Sony</name>
   </stock>
   <stock>
     <name>Panasonic</name>
     <substocks>
          <stock>
             <name>Panasonic Shop 2</name>
          </stock>
     </substocks>
   </stock>
</city>

Answer 1

我推荐你使用XPath与 javax.xml.xpath包裹:

final InputStream is = new FileInputStream('your.xml');

final DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
final DocumentBuilder builder = factory.newDocumentBuilder();
final Document doc = builder.parse(is);
final XPathFactory xPathfactory = XPathFactory.newInstance();
final XPath xpath = xPathfactory.newXPath();
final XPathExpression expr = xpath.compile("/city/stock/name[text()='Sony']");

然后:

final NodeList nl = (NodeList) expr.evaluate(doc, XPathConstants.NODESET);