SAX解析XML文档

package com.bird.sax;

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;

/**
 * @use SAX解析
 * @author Bird
 *
 */
public class XmlReader {
	public static void main(String [] args) throws Exception{
		// 获得工厂
		SAXParserFactory factory = SAXParserFactory.newInstance();
		
		//获得解析器
		SAXParser sp = factory.newSAXParser();
		
		//获取读取器
		XMLReader reader = sp.getXMLReader();
		
		//设置内容处理器
		reader.setContentHandler(new ValuesHandle());
		//读取XML文档的内容
		reader.parse("d://book.xml");
	}
}


class ValuesHandle extends DefaultHandler{//只解析作者的名字
	private String currentTag ;//记住当前想要解析的标签 
	private int needNumber = 2;//记住你想要的标签的位置
	private int currentNumber; //当前解析的是第几个

	@Override
	public void characters(char[] ch, int start, int length)
			throws SAXException {
		if("作者".equals(currentTag) && currentNumber == needNumber){
			System.out.println(new String(ch,start,length));
		}
	}

	@Override
	public void endElement(String uri, String localName, String qName)
			throws SAXException {
		currentTag = null;
	}

	@Override
	public void startElement(String uri, String localName, String qName,
			Attributes attributes) throws SAXException {
		currentTag = qName;
		if(currentTag.equals("作者")){
			currentNumber++;
		}
	}
	
}

class ListHandle implements ContentHandler{

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

	@Override
	public void endDocument() throws SAXException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void endElement(String uri, String localName, String qName)
			throws SAXException {
		// TODO Auto-generated method stub
		
	}

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

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

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

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

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

	@Override
	public void startDocument() throws SAXException {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void startElement(String uri, String localName, String qName,
			Attributes atts) throws SAXException {
		System.out.println("<" + qName + ">");
		for(int i = 0; atts != null && i < atts.getLength(); i++){//注意这种写法
			String  name = atts.getQName(i);
			String values = atts.getValue(i);
			System.out.println(name +  " " + values);
		}
	}

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