java xml dom解析

Question

我正在开发这个项目，我想解析一个如下所示的 xml 文件：

<?xml version='1.0' encoding='UTF-8'?>
<projectlist>
  <project>
    <name>SuperDuperApp</name>
    <type>batch</type>
    <prod>
      <server>testserver01</server>
    </prod>
    <qa>
      <server>testserver01</server>
    </qa>
    <dev>
      <server>testserver01</server>
    </dev>
  </project>
  <project>
    <name>Calculator</name>
    <type>deploy</type>
    <prod>
      <server>testserver02</server>
      <server>testserver03</server>
      <server>testserver04</server>
    </prod>
    <qa>
      <server>testserver05</server>
      <server>testserver06</server>
      <server>testserver07</server>
    </qa>
    <dev>
      <server>testserver12</server>
      <server>testserver13</server>
      <server>testserver14</server>
    </dev>
  </project>
</projectlist>

使用此方法解析文件并尝试以以下格式打印：

name: SuperDuperApp
type: batch
server: testserver01

name: Calculator
type: deploy
environment: dev
server: testserver12
server: testserver13
server: testserver14

etc.
public void parseXML() {
     ArrayList al = new ArrayList();
     HashSet hs = new HashSet();
    try {
        InputStream file = this.getClass().getResourceAsStream(
                "/net/swing/sandbox/util/config/projectlist.xml");
        DocumentBuilderFactory dbFactory = DocumentBuilderFactory
                .newInstance();
        DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
        Document doc = dBuilder.parse(file);
        doc.getDocumentElement().normalize();

        System.out.println("Root element: " + doc.getDocumentElement().getNodeName());

        NodeList nList = doc.getElementsByTagName("project");

        System.out.println("Information of all servers...");

        for (int i=0;i<nList.getLength();i++){
            Node fstNode = nList.item(i);

            if (fstNode.getNodeType() == Node.ELEMENT_NODE) {
                Element fstElement = (Element) fstNode;

                NodeList nameElementList = fstElement.getElementsByTagName("name");
                Element nameElement = (Element) nameElementList.item(0);
                NodeList name = nameElement.getChildNodes();
                System.out.println("project name: " + ((Node) name.item(0)).getNodeValue());
                hs.add(((Node) name.item(0)).getNodeValue());

                NodeList typeElementList = fstElement.getElementsByTagName("type");
                Element typeElement = (Element) typeElementList.item(0);
                NodeList type = typeElement.getChildNodes();
                System.out.println("Deploy type: " + ((Node) type.item(0)).getNodeValue());

                //print out server list can't do it for some reason         
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }


     try {
     al.clear();
     al.addAll(hs);
     Collections.sort(al);
     for (int z = 0; z < al.size(); z++) {
     listModel.addElement(al.get(z));
     }
     } catch (Exception e) {
     e.printStackTrace();
     }
     lstProject.validate();

}

所以我重写了我的方法，现在我陷入了困境 < ;---新人

Answer 1

查看 Node 的文档。每个节点都有一个方法 getChildNodes。检查子节点是否存在，然后像您所做的那样迭代它们。

Answer 2

如果您的 xml 是使用 xsd 模式创建的，则可以使用 JAXB 为其创建类，并使用 xjc工具。这应该会让你的生活更轻松一些。

Answer 3

我认为在您的情况下使用 XSLT 转换是合适的（更少的样板代码）请参阅 TransformerFactory 和用于 xml 处理的 java api。

Answer 4

作为问答解决方案，您可以应用与获取“项目”节点相同的策略：

...
System.out.println("servers:");

NodeList sList = eElement.getElementsByTagName("server");
for (int i = 0; i < sList.getLength(); i++) {
    String stuff = sList.item(i).getFirstChild().getNodeValue();
    System.out.println(stuff);
}