使用SAX解析xml

样例，解析器:

package com.mogu.parse;

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

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

import com.mogu.dto.User;

import android.util.Log;

public class MySAXHandler extends DefaultHandler {

        private String tagName;
        private StringBuffer sBuffer;
        private List<User> userList;
        private User user;

        public List<User> getUserList() {
                return userList;
        }

        @Override
        public void startDocument() throws SAXException {
                userList = new ArrayList<User>();
                sBuffer = new StringBuffer();
                Log.d("FirstSAX", "start parse xml file");
        }

        @Override
        public void endDocument() throws SAXException {
                Log.d("FirstSAX", "parse xml file end");
        }

        @Override
        public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
                tagName = localName;
                sBuffer.setLength(0);
                if ("user".equals(localName)) {
                        user = new User();
                        user.setId(Integer.parseInt(attributes.getValue("id")));
                }
        }

        @Override
        public void endElement(String uri, String localName, String qName) throws SAXException {
                if ("user".equals(localName)) {
                        userList.add(user);
                        user = null;
                } else if ("name".equals(localName)) {
                        user.setName(sBuffer.toString());
                } else if ("age".equals(localName)){
                        user.setAge(Integer.parseInt(sBuffer.toString()));
                }
                tagName = null;
        }

        @Override
        public void characters(char[] ch, int start, int length) throws SAXException {
                if (tagName != null) {
                        sBuffer.append(new String(ch, start, length));
                }
        }

}

实体类：

package com.mogu.dto;

public class User {
        
        private int id;
        private String name;
        private int age;
        
        public int getId() {
                return id;
        }
        public void setId(int id) {
                this.id = id;
        }
        public String getName() {
                return name;
        }
        public void setName(String name) {
                this.name = name;
        }
        public int getAge() {
                return age;
        }
        public void setAge(int age) {
                this.age = age;
        }
        
        @Override
        public String toString() {
                return "姓名：" + name +"；年龄：" + age;
        }

}

activity:

package com.mogu.firstsax;

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

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

import org.xml.sax.SAXException;

import com.lidroid.xutils.ViewUtils;
import com.lidroid.xutils.view.annotation.ViewInject;
import com.lidroid.xutils.view.annotation.event.OnClick;
import com.mogu.dto.User;
import com.mogu.parse.MySAXHandler;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;

public class MainActivity extends Activity {

        @ViewInject(R.id.btn_parse)
        private Button btn_parse;

        @ViewInject(R.id.lv_main)
        private ListView lv_main;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                // 设置无标题
                requestWindowFeature(Window.FEATURE_NO_TITLE);
                // 设置全屏
                getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
                setContentView(R.layout.activity_main);
                ViewUtils.inject(this);
        }

        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
                // Inflate the menu; this adds items to the action bar if it is present.
                getMenuInflater().inflate(R.menu.main, menu);
                return true;
        }

        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
                // Handle action bar item clicks here. The action bar will
                // automatically handle clicks on the Home/Up button, so long
                // as you specify a parent activity in AndroidManifest.xml.
                int id = item.getItemId();
                if (id == R.id.action_settings) {
                        return true;
                }
                return super.onOptionsItemSelected(item);
        }

        @OnClick(R.id.btn_parse)
        private void startParse(View v) {
                InputStream file = null;
                try {
                        file = getAssets().open("user.xml");
                        try {
                                // 创建一个SAXParserFactory
                                SAXParserFactory factory = SAXParserFactory.newInstance();
                                // ②创建SAX解析器
                                SAXParser parser = factory.newSAXParser();
                                MySAXHandler mySAXHandler = new MySAXHandler();
                                parser.parse(file, mySAXHandler);
                                List<User> userList = mySAXHandler.getUserList();
                                System.out.println("userList:" + userList);
                                ArrayAdapter<User> adapter = new ArrayAdapter<User>(MainActivity.this,
                                                android.R.layout.simple_expandable_list_item_1, userList);
                                lv_main.setAdapter(adapter); 
                        } catch (SAXException | ParserConfigurationException e) {
                                e.printStackTrace();
                        }
                        // List<User>
                } catch (IOException e) {
                        e.printStackTrace();
                } finally {
                        if (file != null) {
                                try {
                                        file.close();
                                } catch (IOException e) {
                                        e.printStackTrace();
                                }
                        }
                }
        }
}

被解析的xml文件：

<?xml version="1.0" encoding="UTF-8"?>
<users>
        <user id="1">
            <name>jack</name>
            <age>20</age>
        </user>
        <user id="2">
            <name>lucy</name>
            <age>21</age>
        </user>    
</users>