遍历DOM树以获取（名称，值）属性对和叶节点对

我想遍历DOM中的XML文件，以便检索所有的（名称，值）对：

1. 属性名称和值;
2. 所有叶节点名称及其文本内容;

因此，以下面的XML文件为例：

我想要的名称值对是：

 text=title1 id=comment1 data=abcd data=efgh id=commment2 data=ijkl data=mnop data=qrst 

Answer 1

更简单的解决方案可能是使用XPath提取所有名称值对，如以下示例所示。 您还可以跳过DOM构造并直接在InputSource上调用evaluate。 XPath表达式

 //@* | //*[not(*)] 

匹配所有属性的联合以及没有任何子节点的所有节点。

 import java.io.StringReader; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.xpath.XPath; import javax.xml.xpath.XPathConstants; import javax.xml.xpath.XPathFactory; import org.w3c.dom.Document; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.xml.sax.InputSource; public class Test { private static final String xml = "\n"; public static void main(String[] args) throws Exception { DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document doc = builder.parse(new InputSource(new StringReader(xml))); XPathFactory xpf = XPathFactory.newInstance(); XPath xp = xpf.newXPath(); NodeList nodes = (NodeList)xp.evaluate("//@* | //*[not(*)]", doc, XPathConstants.NODESET); System.out.println(nodes.getLength()); for (int i=0, len=nodes.getLength(); i 

Answer 2

怎么样的：

  String xml = "\n" + "\n"; try { DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document doc = builder.parse(new InputSource(new StringReader(xml))); DocumentTraversal traversal = (DocumentTraversal) doc; NodeIterator iterator = traversal.createNodeIterator( doc.getDocumentElement(), NodeFilter.SHOW_ELEMENT, null, true); for (Node n = iterator.nextNode(); n != null; n = iterator.nextNode()) { //System.out.println("Element: " + ((Element) n).getTagName()); String tagname = ((Element) n).getTagName(); if(tagname.equals("title")) { System.out.println("text=" + ((Element)n).getAttribute("text")); } else if(tagname.equals("comment")) { System.out.println("id=" + ((Element)n).getAttribute("id")); } else if(tagname.equals("data")) { System.out.println("data=" + ((Element)n).getTextContent()); } else { System.out.println("Unhandled element"); } } } catch (Exception e) { e.printStackTrace(); } 

好的，所以你对此不满意，怎么样：

  String xml = "\n" + "\n"; try { DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document doc = builder.parse(new InputSource(new StringReader(xml))); DocumentTraversal traversal = (DocumentTraversal) doc; NodeIterator iterator = traversal.createNodeIterator( doc.getDocumentElement(), NodeFilter.SHOW_ELEMENT, null, true); for (Node n = iterator.nextNode(); n != null; n = iterator.nextNode()) { //System.out.println("Element: " + ((Element) n).getTagName()); String tagname = ((Element) n).getTagName(); NamedNodeMap map = ((Element)n).getAttributes(); if(map.getLength() > 0) { for(int i=0; i