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")));
		
	}
	
	

}