問題描述

從給定的 XML 字符串，我必須更新結束日期值.即使我在 updateNodeValue() 方法中更新 xml，我的最終輸出 xml 與輸入 xml 相同.

From the given XML String, i have to update End Date value . Even though I'm updating the xml in updateNodeValue() method, my final output xml is same as the input xml.

誰能告訴我這段代碼有什么錯誤

Can someone tell me what is the mistake in this code

import java.io.StringReader;
import java.io.StringWriter;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;


public class MyClass{

    static String strXml = "<INFO><BeginDate>2013-12-02</BeginDate><EndDate>2014-01-31</EndDate></INFO>";

    public static void main(String[] args) throws Exception {

        System.out.println(strXml);
        Document doc = StringToDocument(strXml);
        updateNodeValue(doc);
        String newxml = DocumentToString(doc);
        System.out.println(newxml);

    }

    public static void updateNodeValue(Document doc) {

        Node rootNode = doc.getFirstChild();
        NodeList list = rootNode.getChildNodes();
        for (int i = 0; i < list.getLength(); i++) {

            Element element = (Element) list.item(i);
            Node node = list.item(i);
            if ("EndDate".equals(node.getNodeName())) {
                element.setNodeValue("2013-12-12");
                return;
            }
        }
    }

    public static String DocumentToString(Document doc) throws Exception {

        TransformerFactory tf = TransformerFactory.newInstance();
        Transformer transformer = tf.newTransformer();
        transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
        StringWriter writer = new StringWriter();
        transformer.transform(new DOMSource(doc), new StreamResult(writer));
        String output = writer.getBuffer().toString();
        return output;
    }

    public static Document StringToDocument(String strXml) throws Exception {

        Document doc = null;
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            StringReader strReader = new StringReader(strXml);
            InputSource is = new InputSource(strReader);
            doc = (Document) builder.parse(is);
        } catch (Exception e) {
            e.printStackTrace();
            throw e;
        }

        return doc;
    }
}

推薦答案

在你的 updateNodeValue 方法中使用element.setTextContent(...).

Useelement.setTextContent(...) in your updateNodeValue method.

這篇關于更新 XML 字符串的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！