java xml检索命名参数

这就是我被困的地方。我找不到通过“name”设置其中一个param元素的值的方法

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我使用的是java 1.7，您需要键入要键入的每个节点，以便能够设置文本和属性。你可能想看看，它简化了这样的事情

String xmlfile = "path\\to\\file.xml"
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.parse(xmlfile);

//get the params element
Node params = doc.getElementsByTagName("params").item(0);

//get a list of nodes in the params element
NodeList param = params.getChildNodes();

NodeList params=doc.getElementsByTagName（“param”）；
对于（int i=0；i

我建议对其使用XPath查询。语法类似于

/root/program/params/param[@name='name2']

。有关xpath设置，请参阅xpath看起来很有趣。我将研究这个解决方案

String xmlfile = "path\\to\\file.xml"
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.parse(xmlfile);

//get the params element
Node params = doc.getElementsByTagName("params").item(0);

//get a list of nodes in the params element
NodeList param = params.getChildNodes();

import javax.xml.parsers.*;
import javax.xml.xpath.*;
import org.w3c.dom.*;

public class Demo {

    public static void main(String[] args) throws Exception {
        String xmlfile = "src/forum17753835/file.xml";
        DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
        Document doc = docBuilder.parse(xmlfile);

        XPathFactory xpathFactory = XPathFactory.newInstance();
        XPath xpath = xpathFactory.newXPath();
        Element element = (Element) xpath.evaluate("/root/program/params/param[@name='name2']", doc, XPathConstants.NODE);
        System.out.println(element.getTextContent());
    }

}

  NodeList params = doc.getElementsByTagName("param");
  for (int i = 0; i < params.getLength(); i++)
  {
     if (params.item(i).getAttributes().getNamedItem("name").getNodeValue().equals("name2"))
     {
        // do smth with element <param name='name2'>test2</param>
        // that is params.item(i) in current context
     }
  }