使用SAX方式解析XML文件

package com.pingyijinren.test;import android.util.Log;import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;/**
 * Created by Administrator on 2016/5/19 0019.
 */
public class ContentHandler extends DefaultHandler {
    private String nodeName;
    private StringBuilder id;
    private StringBuilder name;
    private StringBuilder version;    @Override
    public void startDocument() throws SAXException{
        id=new StringBuilder();
        name=new StringBuilder();
        version=new StringBuilder();
    }    @Override
    public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException{
        nodeName=localName;
    }    @Override
    public void characters(char[] ch,int start,int length) throws SAXException{
        if(nodeName.equals("id")){
            id.append(ch,start,length);
        }
        else if(nodeName.equals("name")){
            name.append(ch,start,length);
        }
        else if(nodeName.equals("version")){
            version.append(ch,start,length);
        }
    }    @Override
    public void endElement(String uri,String localName,String qName) throws SAXException{
        if(localName.equals("app")){
            Log.d("MainActivity","id is "+id.toString().trim());
            Log.d("MainActivity","name is "+name.toString().trim());
            Log.d("MainActivity","version is "+version.toString().trim());            id.setLength(0);
            name.setLength(0);
            version.setLength(0);
        }
    }    @Override
    public void endDocument() throws SAXException{}
}

package com.pingyijinren.test;import android.content.Intent;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.xml.sax.InputSource;
import org.xml.sax.XMLReader;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;import java.io.BufferedReader;
import java.io.EOFException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.net.HttpURLConnection;
import java.net.URL;import javax.xml.parsers.SAXParserFactory;public class MainActivity extends AppCompatActivity{
    private Button button;
    private TextView textView;
    private static final int SHOW_RESPONSE=0;
    private Handler handler=new Handler(){
        public void handleMessage(Message message){
            switch(message.what){
                case SHOW_RESPONSE:
                    String response=(String)message.obj;
                    textView.setText(response);
            }
        }
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);        button=(Button)findViewById(R.id.button);
        textView=(TextView)findViewById(R.id.textView);        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                sendRequestWithHttpURLConnection();
            }
        });
    }    private void sendRequestWithHttpURLConnection(){
        new Thread(new Runnable(){
            @Override
            public void run(){
                try{
                    HttpClient httpClient = new DefaultHttpClient();
                    HttpGet httpGet=new HttpGet("http://172.29.209.1/get_data.xml");
                    HttpResponse httpResponse=httpClient.execute(httpGet);
                    if(httpResponse.getStatusLine().getStatusCode()==200){
                        HttpEntity httpEntity=httpResponse.getEntity();
                        String response= EntityUtils.toString(httpEntity,"utf-8");                        Log.d("MainActivity",response);                        parseXMLWithSAX(response);
                    }
                }
                catch(Exception e){
                    e.printStackTrace();
                }            }
        }).start();
    }    private void parseXMLWithSAX(String xmlData){
        try{
            SAXParserFactory factory=SAXParserFactory.newInstance();
            XMLReader xmlReader=factory.newSAXParser().getXMLReader();
            ContentHandler handler=new ContentHandler();
            xmlReader.setContentHandler(handler);
            xmlReader.parse(new InputSource(new StringReader(xmlData)));
        }
        catch(Exception e){
            e.printStackTrace();
        }
    }
}