源代码：
package com.zc.homeWork18;
import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class XMLWriter {
private static String xmlPath = "src\\com\\zc\\homeWork18\\MyXml.xml";
public static void getFamilyMemebers() {
/*
* 创建文件工厂实例
*/
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
// 如果创建的解析器在解析XML文档时必须删除元素内容中的空格，则为true，否则为false
dbf.setIgnoringElementContentWhitespace(true);
try {
/*
* 创建文件对象
*/
DocumentBuilder db = dbf.newDocumentBuilder();// 创建解析器，解析XML文档
Document doc = db.parse(xmlPath); // 使用dom解析xml文件
/*
* 历遍列表，进行XML文件的数据提取
*/
// 根据节点名称来获取所有相关的节点
NodeList sonlist = doc.getElementsByTagName("son");
for (int i = 0; i < sonlist.getLength(); i++) // 循环处理对象
{
// 节点属性的处理
Element son = (Element) sonlist.item(i);
// 循环节点son内的所有子节点
for (Node node = son.getFirstChild(); node != null; node = node
.getNextSibling()) {
// 判断是否为元素节点
if (node.getNodeType() == Node.ELEMENT_NODE) {
String name = node.getNodeName();
String value = node.getFirstChild().getNodeValue();
System.out.println(name + " : " + value);
}
}
}
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
// 修改
public static void modifySon() {
// 创建文件工厂实例
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setIgnoringElementContentWhitespace(true);
try {
// 从XML文档中获取DOM文档实例
DocumentBuilder db = dbf.newDocumentBuilder();
// 获取Document对象
Document xmldoc = db.parse(xmlPath);
// 获取根节点
Element root = xmldoc.getDocumentElement();
// 定位id为001的节点
Element per = (Element) selectSingleNode("/father/son[@id='001']",
root);
// 将age节点的内容更改为28
per.getElementsByTagName("age").item(0).setTextContent("28");
// 保存
TransformerFactory factory = TransformerFactory.newInstance();
Transformer former = factory.newTransformer();
former.transform(new DOMSource(xmldoc), new StreamResult(new File(
xmlPath)));
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
// 获取目标节点，进行删除，最后保存
public static void discardSon() {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setIgnoringElementContentWhitespace(true);
try {
DocumentBuilder db = dbf.newDocumentBuilder();
Document xmldoc = db.parse(xmlPath);
// 获取根节点
Element root = xmldoc.getDocumentElement();
// 定位根节点中的id=002的节点
Element son = (Element) selectSingleNode("/father/son[@id='002']",
root);
// 删除该节点
root.removeChild(son);
// 保存
TransformerFactory factory = TransformerFactory.newInstance();
Transformer former = factory.newTransformer();
former.transform(new DOMSource(xmldoc), new StreamResult(new File(
xmlPath)));
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
// 新增节点
public static void createSon() {
// 创建文件工厂实例
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setIgnoringElementContentWhitespace(false);
try {
DocumentBuilder db = dbf.newDocumentBuilder();
// 创建Document对象
Document xmldoc = db.parse(xmlPath);
// 获取根节点
Element root = xmldoc.getDocumentElement();
// 创建节点son，设置对应的id为004
Element son = xmldoc.createElement("son");
son.setAttribute("id", "004");
// 创建节点name
Element name = xmldoc.createElement("name");
name.setTextContent("小儿子");
son.appendChild(name);
// 创建节点age
Element age = xmldoc.createElement("age");
age.setTextContent("0");
son.appendChild(age);
// 把son添加到根节点中
root.appendChild(son);
// 保存
TransformerFactory factory = TransformerFactory.newInstance();
Transformer former = factory.newTransformer();
former.transform(new DOMSource(xmldoc), new StreamResult(new File(
xmlPath)));
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
// 修改节点信息
public static Node selectSingleNode(String express, Element source) {
Node result = null;
//创建XPath工厂
XPathFactory xpathFactory = XPathFactory.newInstance();
//创建XPath对象
XPath xpath = xpathFactory.newXPath();
try {
result = (Node) xpath.evaluate(express, source, XPathConstants.NODE);
System.out.println(result);
} catch (XPathExpressionException e) {
System.out.println(e.getMessage());
}
return result;
}
// 打印
public static void main(String[] args) {
getFamilyMemebers();
System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
modifySon();
System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
System.out.println("修改数据");
getFamilyMemebers();
System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
discardSon();
System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
System.out.println("删除数据");
getFamilyMemebers();
System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
createSon();
System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
System.out.println("添加数据");
getFamilyMemebers();
}
}
XML文件
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<father>
<son id="001">
<name>老大</name>
<age>20</age>
</son>
<son id="002">
<name>老二</name>
<age>18</age>
</son>
<son id="003">
<name>老三</name>
<age>13</age>
</son>
</father>