android-HttpURLConnection

package zhang.example;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class http extends Activity {
	private Button go;
	private TextView web;
	private final String DEBUG_TAG="Activity02";
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        go=(Button)findViewById(R.id.button1);
        web=(TextView)findViewById(R.id.textView1);
        
        go.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				// TODO Auto-generated method stub
				try {
					refresh();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		});
       new Thread(mRunnable).start();
     
    }
    
    public void refresh() throws IOException{
    	String httpurl="http://wap.baidu.com";
    	String resultData="";
    	URL url =null;
    	
    	try{
    		url= new URL(httpurl);
    		
    	}catch (Exception e) {
			// TODO: handle exception
    		e.printStackTrace();
		}
    	if(url!=null){
    		try{
    		HttpURLConnection urlconn=(HttpURLConnection)url.openConnection();
    		InputStreamReader in=new InputStreamReader(urlconn.getInputStream());
    		BufferedReader buffer=new BufferedReader(in);
    		String inputLine=null;
    		while(((inputLine=buffer.readLine())!=null)){
    			resultData+=inputLine+"\n";
    		}
    		in.close();
    		urlconn.disconnect();
    	if(resultData!=null){
    		web.setText(resultData);
    	}else{
    		web.setText("null");
    	}
    	}catch (Exception e) {
			// TODO: handle exception
    		e.printStackTrace();
		}
    }
    	else{
    		Log.e(DEBUG_TAG,"urlnull");
    	}
    }
    private Runnable mRunnable=new Runnable(){
    	public void run(){
    		while(true){
    			try{
    				Thread.sleep(5000);
    				mHandler.sendMessage(mHandler.obtainMessage());
    			}catch (Exception e) {
					// TODO: handle exception
    				e.printStackTrace();
				}
    		}
    	}
    };
    Handler mHandler =new Handler(){
    	public void handleMessage(Message msg){
    		super.handleMessage(msg);
    		try {
				refresh();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
    	}
    };
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:orientation="vertical" android:layout_width="fill_parent"
	android:layout_height="fill_parent">
	<Button android:text="Button" android:id="@+id/button1"
		android:layout_width="wrap_content" android:layout_height="wrap_content"></Button>
		<ScrollView android:layout_width="fill_parent" android:layout_height="match_parent">
	<TextView android:text="@string/hello" android:id="@+id/textView1"
		android:scrollHorizontally="true"
		android:layout_width="fill_parent" android:layout_height="wrap_content"></TextView>
		</ScrollView>
</LinearLayout>