SAX流机制解析器

Posted 2020-12-28 yuexiaoyun

 

1.基本的xml文档

<?xml version="1.0" encoding="UTF-8" ?>
<persons>
    <person>
        <name>Jim</name>
        <age>45</age>
    </person>
    <person>
        <name>Ann</name>
        <age>36</age>
    </person>
</persons>

2.封装值的封装类

package com.dasenlin.prasexml;
/**
 * 封装类
 * @author Administrator
 *
 */
public class Persons {
    private String name;
    private Integer age;

    public Persons() {
        super();
    }

    public Persons(String name, Integer age) {
        super();
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }


}

3.解析的流程逻辑类

package com.dasenlin.prasexml;

import java.io.IOException;
import java.util.List;

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

import org.xml.sax.SAXException;

/**
 * 用SAX解析xml
 * @author Administrator
 *
 */
public class ParseXml {

    public static void main(String[] args) {
            //1.创建解析工厂
        SAXParserFactory factory =SAXParserFactory.newInstance();
            //2.获取解析器
        try {
            SAXParser parse =factory.newSAXParser();
            //3.加载文档Document注册处理器
            //4.编写处理器
            PersonHandler handler=new PersonHandler();
            parse.parse(Thread.currentThread().getContextClassLoader().getResourceAsStream("com/dasenlin/prasexml/persons.xml"),handler);
            List <Persons> person = handler.getPersons();
            for(Persons any:person){
                System.out.println("name:"+any.getName()+"	age:"+any.getAge());
            }
        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        } catch (SAXException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}

4.手写处理类

package com.dasenlin.prasexml;

import java.util.ArrayList;
import java.util.List;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * 编写的处理器
 * @author Administrator
 *
 */
public class PersonHandler extends DefaultHandler {
    private List<Persons> persons;
    private Persons person;
    private String tag;

    public List<Persons> getPersons() {
        return persons;
    }

    public void setPersons(List<Persons> persons) {
        this.persons = persons;
    }

    @Override//开始文档
    public void startDocument() throws SAXException {
        persons =new ArrayList<Persons>();
    }

    @Override//开始元素
    public void startElement(String uri, String localName, String qName,
            Attributes attributes) throws SAXException {
        if(null!=qName){
            tag=qName;
        }
        if(null!=qName && qName.equals("person")){
            person = new Persons();
        }
    }

    @Override//String
    public void characters(char[] ch, int start, int length) throws SAXException {
        String str = new String(ch,start,length);
        if(null!=tag&&tag.equals("name")){
            person.setName(str);
        }else if(null!=tag&&tag.equals("age")){
            Integer age = Integer.parseInt(str);
            person.setAge(age);
        }
    }

    @Override//结束元素
    public void endElement(String uri, String localName, String qName)
            throws SAXException {
        if(qName.equals("person")){
            this.persons.add(person);
        }
        tag=null;
    }

    @Override//结束文档
    public void endDocument() throws SAXException {
        // TODO 自动生成的方法存根
        super.endDocument();
    }
}