Java_XML操作

xml的写：

code：

 import java.io.File;
 import java.io.StringWriter;

 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.transform.Transformer;
 import javax.xml.transform.TransformerConfigurationException;
 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;

 public class WriteXML {

     public static void main(String[] args) {

         try {

             DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
             DocumentBuilder builder = factory.newDocumentBuilder();
             Document document = builder.newDocument();
             Element root =  document.createElement("Languages");
             root.setAttribute("cat", "it");

             Element lan1 = document.createElement("lan");
             lan1.setAttribute("id", "");
             Element name1 = document.createElement("name");
             Element ide1 = document.createElement("ide");
             name1.setTextContent("Java");
             ide1.setTextContent("eclipse");
             lan1.appendChild(name1);
             lan1.appendChild(ide1);

             Element lan2 = document.createElement("lan");
             lan1.setAttribute("id", "");
             Element name2 = document.createElement("name");
             Element ide2 = document.createElement("ide");
             name2.setTextContent("Swift");
             ide2.setTextContent("Xcode");
             lan2.appendChild(name2);
             lan2.appendChild(ide2);

             Element lan3 = document.createElement("lan");
             lan3.setAttribute("id", "");
             Element name3 = document.createElement("name");
             Element ide3 = document.createElement("ide");
             name3.setTextContent("C#");
             ide3.setTextContent("Visual Studio");
             lan3.appendChild(name3);
             lan3.appendChild(ide3);

             root.appendChild(lan1);
             root.appendChild(lan2);
             root.appendChild(lan3);
             document.appendChild(root);

             //-----------------------

             TransformerFactory transformerFactory = TransformerFactory.newInstance();
             Transformer tansformer = transformerFactory.newTransformer();
             StringWriter writer = new StringWriter();
             tansformer.transform(new DOMSource(document), new StreamResult(writer));
             System.out.println(writer.toString());//输出到控制台

             tansformer.transform(new DOMSource(document), new StreamResult(new File("newxml.xml")));//输出到xml文本
         } catch (ParserConfigurationException e) {

             e.printStackTrace();
         } catch (TransformerConfigurationException e) {
             e.printStackTrace();
         } catch (TransformerException e) {

             e.printStackTrace();
         }
     }

 }

xml的读：

code：

 import java.io.File;
 import java.io.IOException;

 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;

 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 TestReadXML {

     public static void main(String[] args) {
         //DOM
         try {
             DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
             DocumentBuilder builder =  factory.newDocumentBuilder();
             Document document =  builder.parse(new File("languages.xml"));
             Element root = document.getDocumentElement();//获取根元素
             System.out.println("cat="+root.getAttribute("cat"));
             NodeList list =    root.getElementsByTagName("lan");//获取子元素lan
             for(int i=;i<list.getLength();i++){
                 Element lan = (Element) list.item(i);
                 System.out.println("--------");
                 System.out.println("id="+lan.getAttribute("id"));

 //                Element name = (Element) lan.getElementsByTagName("name").item(0);//不使用这种方法
 //                System.out.println("name="+name.getTextContent());

                 NodeList clist = lan.getChildNodes();//获取lan的所有子元素
                 for(int j=;j<clist.getLength();j++){
                     Node c = clist.item(j);
                     if(c instanceof Element)
                        System.out.println(c.getNodeName()+"="+c.getTextContent());
                 }
             }

         } catch (ParserConfigurationException e) {

             e.printStackTrace();
         } catch (SAXException e) {

             e.printStackTrace();
         } catch (IOException e) {

             e.printStackTrace();
         }
     }

 }