使用JAXP对xml文档进行Dom解析

package cn.xue.xml;

import java.io.FileOutputStream;
import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.junit.Test;
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;

//使用dom方式对xml文档进行crud
public class Test2 {

//读取xml文档中：<书名>JavaScript网页开发</书名> 节点中的值
@Test
public void read1() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

NodeList list = document.getElementsByTagName("书名");
Node node = list.item(1);
String content = node.getTextContent();
System.out.println(content);
}

//得到xml文档中所有的标签
@Test
public void read2() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

//得到根节点
Node root = document.getElementsByTagName("书架").item(0);

list(root);
}

private void list(Node node) {
if(node instanceof Element){
System.out.println(node.getNodeName());
}
NodeList list = node.getChildNodes();
for(int i = 0; i < list.getLength(); i++)
{
Node child = list.item(i);
list(child);
}
}

//得到xml文档中标签属性的值：<书名 name = "xxxx">Java就业培训教程</书名>
@Test
public void read3() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

Element bookname = (Element) document.getElementsByTagName("书名").item(0);
String value = bookname.getAttribute("name");
System.out.println(value);

}

//向xml文档中添加节点：<售价>59.00元</售价>
@Test
public void add1() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

//创建节点
Element price = document.createElement("售价");
price.setTextContent("59.00元");

//把节点挂在第一本书上
Element book = (Element) document.getElementsByTagName("书").item(0);
book.appendChild(price);

//把更新后的内存写回到xml文档
TransformerFactory tffactory = TransformerFactory.newInstance();
Transformer tf = tffactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));
}

//向xml文档中指定位置插入节点：<售价>59.00元</售价>
@Test
public void add2() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

//创建节点
Element price = document.createElement("售价");
price.setTextContent("59.00元");

//得到参考节点
Element refNode = (Element) document.getElementsByTagName("售价").item(0);

//得到挂崽的节点
Element book = (Element) document.getElementsByTagName("书").item(0);

//往book节点的指定位置挂崽
book.insertBefore(price, refNode);

//把更新后的内存写回到xml文档
TransformerFactory tffactory = TransformerFactory.newInstance();
Transformer tf = tffactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));
}

//向xml文档节点上添加属性：<书名>Java就业培训教程</书名>上添加name="xxxx"属性
@Test
public void addAttr() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

Element bookname = (Element) document.getElementsByTagName("书名").item(0);

bookname.setAttribute("name", "xxxx");

//把更新后的内存写回到xml文档
TransformerFactory tffactory = TransformerFactory.newInstance();
Transformer tf = tffactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));
}

@Test
public void delete1() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

//得到要删除的节点
Element e = (Element) document.getElementsByTagName("售价").item(0);

//得到要删除节点的爸爸
Element book = (Element) document.getElementsByTagName("书").item(0);

//爸爸再删崽
book.removeChild(e);

//把更新后的内存写回到xml文档
TransformerFactory tffactory = TransformerFactory.newInstance();
Transformer tf = tffactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));

}

//删除整个xml文档
@Test
public void delete2() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

//得到要删除的节点
Element e = (Element) document.getElementsByTagName("售价").item(0);
e.getParentNode().getParentNode().getParentNode().removeChild(e.getParentNode().getParentNode());

//把更新后的内存写回到xml文档
TransformerFactory tffactory = TransformerFactory.newInstance();
Transformer tf = tffactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));
}

@Test
public void update() throws Exception{

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse("src/book.xml");

Element e = (Element) document.getElementsByTagName("售价").item(0);
e.setTextContent("109.00元");

//把更新后的内存写回到xml文档
TransformerFactory tffactory = TransformerFactory.newInstance();
Transformer tf = tffactory.newTransformer();
tf.transform(new DOMSource(document), new StreamResult(new FileOutputStream("src/book.xml")));

}

}