SAX And DOM 解析

package com.licheng.www;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;

public class SaxDemo1 {

	/**
	 * @param args
	 * @throws SAXException
	 * @throws ParserConfigurationException
	 */
	public static void main(String[] args) throws Exception {
		// 1,获取解析器工厂
		SAXParserFactory factory = SAXParserFactory.newInstance();
		// 2,通过工厂获取Sax解析器
		SAXParser parser = factory.newSAXParser();
		// 3，获取读取器
		XMLReader reader = parser.getXMLReader();
		// 注册事件处理器
		reader.setContentHandler(new MyContentHandler2());
		// 5,解析XML
		reader.parse("1.xml");

	}

}

// 适配器设计模式
class MyContentHandler2 extends DefaultHandler {
	private String eleName;

	public void startElement(String uri, String localName, String name,
			Attributes attributes) throws SAXException {
		this.eleName = name;

	}

	public void characters(char[] ch, int start, int length)
			throws SAXException {
		if ("海淀".equals(eleName)) {
			System.out.println(new String(ch, start, length));
		}

	}

	public void endElement(String uri, String localName, String name)
			throws SAXException {
		eleName = null;
	}

}

class MyContentHandler implements ContentHandler {
	public void startDocument() throws SAXException {
		System.out.println("文档解析开始了");

	}

	public void startElement(String uri, String localName, String name,
			Attributes atts) throws SAXException {
		System.out.println("发现了开始标签" + name);
	}

	public void characters(char[] ch, int start, int length)
			throws SAXException {
		System.out.println(new String(ch, start, length));

	}

	public void endElement(String uri, String localName, String name)
			throws SAXException {

		System.out.println("发现了结束标签" + name);

	}

	public void endDocument() throws SAXException {
		System.out.println("文档解析结束了");

	}

	public void setDocumentLocator(Locator locator) {
		// TODO Auto-generated method stub

	}

	public void skippedEntity(String name) throws SAXException {
		// TODO Auto-generated method stub

	}

	public void startPrefixMapping(String prefix, String uri)
			throws SAXException {
		// TODO Auto-generated method stub

	}

	public void endPrefixMapping(String prefix) throws SAXException {
		// TODO Auto-generated method stub

	}

	public void ignorableWhitespace(char[] ch, int start, int length)
			throws SAXException {
		// TODO Auto-generated method stub

	}

	public void processingInstruction(String target, String data)
			throws SAXException {
		// TODO Auto-generated method stub

	}

}

1.xml

<?xml version="1.0" encoding="utf-8" ?>
<中国>
	<北京>
		<海淀>  > <  </海淀>
		<丰台></丰台>
		</北京>
</中国>
<!--  
aa a ad
--> 

Dom4j  Dom  解析

package com.licheng.dom4j;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

public class Dom4jTest {

	/**
	 * @param args
	 * @throws Exception
	 */
	public static void main(String[] args) throws Exception {
		// TODO Auto-generated method stub
		// 获取解析器
		SAXReader reader = new SAXReader();
		// 解析xml获取代表整个文档的 dom对象
		Document dom = reader.read("1.xml");
		// 获取根节点
		Element root = dom.getRootElement();
		//获取
		String cityName=root.element("北京").element("海淀").getText();
		System.out.println(cityName);
	}

}

package com.licheng.dom4j;

import java.io.FileOutputStream;
import java.io.FileWriter;
import java.util.List;

import org.dom4j.Document;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

public class Dom4jTest2 {

	public static void find() throws Exception {

		SAXReader reader = new SAXReader();
		Document dom = reader.read("1.xml");
		Element root = dom.getRootElement();
		List list = root.elements();
		Element city = (Element) list.get(0);
		System.out.println(city.element("海淀").getText());

	}

	public static void add() throws Exception {

		SAXReader reader = new SAXReader();
		Document dom = reader.read("1.xml");
		Element root = dom.getRootElement();
		// 创建节点
		Element cityEle = DocumentHelper.createElement("东城");
		cityEle.setText("哈哈");
		// 挂载
		Element city = root.element("北京");
		city.add(cityEle);

		// 将内存中的dom树回写到xml文件中，从而使xml中的数据更新
		// FileWriter writer=new FileWriter("1.xml");
		// dom.write(writer);
		// writer.flush();
		// writer.close();
		XMLWriter writer = new XMLWriter(new FileOutputStream("1.xml"),
				OutputFormat.createCompactFormat());
		writer.write(dom);
		writer.close();

	}

	public static void update() throws Exception {

		SAXReader reader = new SAXReader();
		Document dom = reader.read("1.xml");
		Element root = dom.getRootElement();
		root.element("北京").element("海淀").setText("1111");
		XMLWriter writer = new XMLWriter(new FileOutputStream("1.xml"),
				OutputFormat.createCompactFormat());
		writer.write(dom);
		writer.close();

	}

	public static void del() throws Exception {

		SAXReader reader = new SAXReader();
		Document dom = reader.read("1.xml");
		Element root = dom.getRootElement();
		Element city=root.element("北京").element("东城");
		city.getParent().remove(city);
		
		XMLWriter writer = new XMLWriter(new FileOutputStream("1.xml"),
				OutputFormat.createCompactFormat());
		writer.write(dom);
		writer.close();
	}

	public static void main(String[] args) {
		try {
			find();
			add();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	//city.addAttribute(arg0, arg1)  添加属性
	//city.attribute(arg0)  获取属性

}