java操作DOM节点的添加，删除，修改

java操作DOM节点的添加，删除，修改

下面我们开始对此xml添加，删除，修改：方法一
import java.io.File;
import java.io.IOException;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.*;
import org.xml.sax.SAXException;
public class DOMConvert
{
    public static void main(String[] args)
    {
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        try
        {
            DocumentBuilder db=dbf.newDocumentBuilder();
            Document doc=db.parse("students.xml");
           
            //------------------添加节点------------------
            //创建表示一个学生信息的各元素节点
            Element eltStu=doc.createElement("student");
            Element eltName=doc.createElement("name");
            Element eltAge=doc.createElement("age");
           
            //创建<student>元素的sn属性节点
            Attr attr=doc.createAttribute("sn");
            attr.setValue("03");
           
            //创建代表学生信息的文本节点
            Text txtName=doc.createTextNode("王五");
            Text txtAge=doc.createTextNode("19");
          
            //将文本节点添加为对应的元素节点的子节点
            eltName.appendChild(txtName);
            eltAge.appendChild(txtAge);
           
            //将name和age节点添加为student节点的子节点
            eltStu.appendChild(eltName);
            eltStu.appendChild(eltAge);
           
            //为<student>元素添加sn属性节点
            eltStu.setAttributeNode(attr);
           
            //得到XML文档的根元素。
            Element eltRoot=doc.getDocumentElement();
           
            //将student节点添加为根元素的子节点
            eltRoot.appendChild(eltStu);
           
            NodeList nl=doc.getElementsByTagName("student");
           
            //------------------删除节点------------------
            Node nodeDel=nl.item(0);
            nodeDel.getParentNode().removeChild(nodeDel);
           
            //------------------修改节点------------------
            //注意：NodeList对象是动态的，所以前面删除节点的操作会影响到NodeList对象，
            //NodeList中的节点对象会重新进行排列，此时，索引为0的节点是先前节点
            //列表中索引为1的节点。
            Element eltChg=(Element)nl.item(0);
            Node nodeAgeChg=eltChg.getElementsByTagName("age").item(0);
            nodeAgeChg.getFirstChild().setNodeValue("22");
           
           
            //输出修改后的学生信息。
            for(int i=0;i<nl.getLength();i++)
            {
                Element elt=(Element)nl.item(i);
                System.out.println("编号："+elt.getAttribute("sn"));
               
                Node nodeName=elt.getElementsByTagName("name").item(0);
                Node nodeAge=elt.getElementsByTagName("age").item(0);
               
                String name=nodeName.getFirstChild().getNodeValue();
                String age=nodeAge.getFirstChild().getNodeValue();
               
                System.out.print("姓名：");
                System.out.println(name);
               
                System.out.print("年龄：");
                System.out.println(age);
                System.out.println("------------------------------------------");
            }
        }
        catch(ParserConfigurationException e){e.printStackTrace();}
        catch(SAXException e){e.printStackTrace();}
        catch(IOException e){e.printStackTrace();}
    }
}
方法二：使用XSL转换实现
import java.io.File;
import java.io.IOException;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.*;
import org.xml.sax.SAXException;
public class DOMConvert2
{
    public static void main(String[] args)
    {
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        try
        {
            DocumentBuilder db=dbf.newDocumentBuilder();
            Document doc=db.parse("students.xml");
           
            Element eltStu=doc.createElement("student");
            Element eltName=doc.createElement("name");
            Element eltAge=doc.createElement("age");
           
            Attr attr=doc.createAttribute("sn");
            attr.setValue("03");
           
            Text txtName=doc.createTextNode("王五");
            Text txtAge=doc.createTextNode("19");
          
            eltName.appendChild(txtName);
            eltAge.appendChild(txtAge);
           
            eltStu.appendChild(eltName);
            eltStu.appendChild(eltAge);
           
            eltStu.setAttributeNode(attr);
           
            Element eltRoot=doc.getDocumentElement();
           
            eltRoot.appendChild(eltStu);
           
            NodeList nl=doc.getElementsByTagName("student");
           
            Node nodeDel=(Element)nl.item(0);
            nodeDel.getParentNode().removeChild(nodeDel);
           
            Element eltChg=(Element)nl.item(0);
            Node nodeAgeChg=eltChg.getElementsByTagName("age").item(0);
            nodeAgeChg.getFirstChild().setNodeValue("22");
           
            //利用文档节点创建一个DOM输入源
            DOMSource source=new DOMSource(doc);
            //以converted.xml文件构造一个StreamResult对象，用于保存转换后结果。
            StreamResult result=new StreamResult(new File("converted.xml"));
           
            //得到转换器工厂类的实例
            TransformerFactory tff = TransformerFactory.newInstance();
            //创建一个新的转换器，用于执行恒等转换，
            //即直接将DOM输入源的内容复制到结果文档中。
            Transformer tf = tff.newTransformer();
            //执行转换
            tf.transform(source, result);
        }
        catch(ParserConfigurationException e){e.printStackTrace();}
        catch(SAXException e){e.printStackTrace();}
        catch(IOException e){e.printStackTrace();}
        catch(TransformerConfigurationException e){e.printStackTrace();}
        catch(TransformerException e){e.printStackTrace();}
    }
}
//students.xml
<?xml version="1.0" encoding="GB2312"?>
<?xml-stylesheet type="text/xsl" href="students.xsl" target="_blank" rel="nofollow">
<students>
    <student sn="01">
        <name>张三</name>
        <age>18</age>
    </student>
   
    <student sn="02">
        <name>李四</name>
        <age>20</age>
    </student>
</students>