我想合并两个 XML 文件（源文件和临时文件）并将结果文件放在源文件中，并且源文件和临时文件具有相同的元素但具有不同的值，例如：

源.xml：

<Main>
   <source>
        <param>
            <entry>
                <key> bla1 </key>
                <value> bla1 </value>
            </entry> 
        </param>
        <Name> name1 </Name>
   </Source> 
</Main>

和temp.xml：

<Main>
   <source>
        <param>
           <entry>
               <key> bla2 </key>
               <value> bla2 </value>
           </entry>
           <entry>
               <key> bla3 </key>
               <value> bla3 </value>
           </entry>  
        </param>
        <Name> name2 </Name>
   </Source> 
</Main>

我想要的期望输出是这样的：

<Main>
  <source>
        <param>
            <entry>
                <key> bla1 </key>
                <value> bla1 </value>
            </entry> 
        </param>
        <Name> name1 </Name>
   </Source> 
   <source>
        <param>

           <entry>
               <key> bla2 </key>
               <value> bla2 </value>
           </entry>
           <entry>
               <key> bla3 </key>
               <value> bla3 </value>
           </entry>  
        </param>
        <Name> name2 </Name>
   </Source> 
</Main>

我正在使用此代码，但它根本不影响source.xml ：

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.StringWriter;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
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.SAXException;

public class MergeXml {

    private static final String fileName = "Source.xml";
    private static final String tempName = "temp.xml";
    private static final String mainTag = "XmlSource";
    private static final String YES = "yes";


    public void mergeXML() throws ParserConfigurationException, SAXException,
            IOException, TransformerException {

        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        DocumentBuilder db = null;
        Document doc = null;
        Document doc2 = null;

        db = dbf.newDocumentBuilder();
        doc = db.parse(new File(fileName));
        doc2 = db.parse(new File(tempName));
        Element tag = doc.createElement(mainTag);

        NodeList nodeList = doc2.getElementsByTagName("*");

        for(int i =0 ; i < nodeList.getLength(); i++){

            Node node = nodeList.item(i);
            if (node.getNodeType() == Node.ELEMENT_NODE) {
                String nodeName = node.getNodeName();
                Element tagChild = doc.createElement((nodeName));

                tag.appendChild(tagChild);
            }
        }

        TransformerFactory tFactory = TransformerFactory.newInstance();
        Transformer transformer = tFactory.newTransformer();
        transformer.setOutputProperty(OutputKeys.INDENT, YES);

        DOMSource source = new DOMSource(doc);
        StreamResult result = new StreamResult(new StringWriter());
        transformer.transform(source, result);

        BufferedWriter output = new BufferedWriter(new FileWriter(fileName));
        String xmlOutput = result.getWriter().toString();
        output.write(xmlOutput);
        output.close();

    }
}

如果需要的话，我的 XML 原始文件：

   <XmlSource>
         <hostName>api.worldweatheronline.com</hostName>
         <parameters>
             <entry>
                 <key>num_of_days</key>
                 <value>1</value>
             </entry>
             <entry>
                 <key>q</key>
                 <value>Cairo</value>
            </entry>
            <entry>
                 <key>format</key>
                 <value>xml</value>
            </entry>
            <entry>
                 <key>key</key>
                 <value>wd63kxr294rcgvbynhaf2z4r</value>
            </entry>
       </parameters>
       <URL>
        http://api.worldweatheronline.com/free/v1/weather.ashx?q=Cairo&format=xml&num_of_days=1&key=wd63kxr294rcgvbynhaf2z4r
      </URL>
      <URLPath>/free/v1/weather.ashx</URLPath>

解决方案

以下是可用于合并两个 xml 的代码片段。

public static void generateDocument(Document root, Document insertDoc, String toPath, String fromPath) {

    if (null != root) {



        try {
              Node element = getNode(insertDoc, fromPath);
              Node dest = root.importNode(element, true);
            Node node = getNode(root, toPath);
            node.insertBefore(dest, null);
        } catch (Exception ex) {
           System.out.println(ex.getMessage());
        }

    }

}
public Node getNode(Document doc, String strXpathExpression)
            throws ParserConfigurationException, SAXException, IOException,
            XPathExpressionException {

        XPath xpath = XPathFactory.newInstance().newXPath();

        // XPath Query for showing all nodes value
        XPathExpression expr = xpath.compile(strXpathExpression);

        Node node = (Node) expr.evaluate(doc, XPathConstants.NODE);

        return node;
    }

因此，您的方法是
1. 创建 Soruce.xml 文档 obj(obj1)
2. 创建 test.xml 文档 obj(obj2) 并删除 Main 标签。

            DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = domFactory.newDocumentBuilder();
            Document doc1 = builder.parse(new File("s1.xml"));
            Document doc2 = builder.parse(new File("s2.xml"));
            generateDocument(doc1,doc2,"/Main", "Main/source");

1. 调用提到的方法generateDocument(obj1, obj2, "/Main")