2.2 使用 JAXP 对XML文档进行SAX解析

使用JAXP 对 XML文档进行 SAX解析：

public class Demo1 {

    /**
     *  使用JAXP对XML文档进行SAX解析
     * @throws Exception 
     * @throws ParserConfigurationException 
     */
    public static void main(String[] args) throws ParserConfigurationException, Exception {
        
        //1.创建解析工厂
         SAXParserFactory factory = SAXParserFactory.newInstance();
        
        //2.得到解析器
         SAXParser sp = factory.newSAXParser();
         
        //3.得到读取器
         XMLReader reader = sp.getXMLReader();
         
        //4.设置内容处理器
         ListHandler handler = new ListHandler();
        reader.setContentHandler(handler);
         
        //5.读取XML文档内容
        reader.parse("src/book.xml");
    }

}

//得到XML文档所有内容
class ListHandler implements ContentHandler {

    @Override
    public void startElement(String uri, String localName, String qName,
            Attributes atts) throws SAXException {
        System.out.println("<" + qName + ">");
        
        //打印标签的属性
        for(int i = 0;atts != null && i<atts.getLength();i++) {  //防止某些时候属性值为空时，抛异常  所以再加个条件atts != null
            String attName = atts.getQName(i);
            String attValue = atts.getValue(i);
            System.out.println(attName + "=" + attValue);
        }
        
    }
    
    @Override
    public void characters(char[] ch, int start, int length)
            throws SAXException {
        System.out.println(new String(ch,start,length));
        
    }
    
    @Override
    public void endElement(String uri, String localName, String qName)
            throws SAXException {
        System.out.println("</" + qName + ">");
        
    }
    
    @Override
    public void setDocumentLocator(Locator locator) {
        
    }
    



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

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

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