Android HttpClient网络通信

package com.Aina.Android;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

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

public class Test extends Activity implements Runnable {
    /** Called when the activity is first created. */
    private Button btn_get = null;
    private Button btn_post = null;
    private TextView tv_rp = null;

    @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            btn_get = (Button) this.findViewById(R.id.Button01);
            btn_post = (Button) this.findViewById(R.id.Button02);
            tv_rp = (TextView) this.findViewById(R.id.TextView);
            btn_get.setOnClickListener(new Button.OnClickListener() {

                public void onClick(View v) {
                    // TODO Auto-generated method stub
                    String httpUrl = "";
                    HttpGet request = new HttpGet(httpUrl);
                    HttpClient httpClient = new DefaultHttpClient();
                    try {
                        HttpResponse response = httpClient.execute(request);
                        if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                            String str = EntityUtils.toString(response.getEntity());
                            tv_rp.setText(str);
                        } else {
                            tv_rp.setText("请求错误");
                        }
                    } catch (ClientProtocolException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }

            });
            btn_post.setOnClickListener(new Button.OnClickListener() {

                public void onClick(View v) {
                    // TODO Auto-generated method stub
                    String httpUrl = "";
                    HttpPost request = new HttpPost(httpUrl);
                    List<NameValuePair> params = new ArrayList<NameValuePair>();
                    params.add(new BasicNameValuePair("par", "request-post"));
                    try {
                        HttpEntity entity = new UrlEncodedFormEntity(params,
                            "UTF-8");
                        request.setEntity(entity);
                        HttpClient client = new DefaultHttpClient();
                        HttpResponse response = client.execute(request);
                        if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                            String str = EntityUtils.toString(response.getEntity());
                            tv_rp.setText(str);
                        } else {
                            tv_rp.setText("请求错误");
                        }
                    } catch (UnsupportedEncodingException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (ClientProtocolException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }

            });
            new Thread(this).start();
        }

    public void refresh() {
        String httpUrl = "";
        try {
            URL url = new URL(httpUrl);
            HttpURLConnection urlConn = (HttpURLConnection) url
                .openConnection();
            urlConn.connect();
            InputStream input = urlConn.getInputStream();
            InputStreamReader inputreader = new InputStreamReader(input);
            BufferedReader reader = new BufferedReader(inputreader);
            String str = null;
            StringBuffer sb = new StringBuffer();
            while ((str = reader.readLine()) != null) {
                sb.append(str).append("\n");
            }
            if (sb != null) {
                tv_rp.setText(sb.toString());
            } else {
                tv_rp.setText("NULL");
            }
            reader.close();
            inputreader.close();
            input.close();
            reader = null;
            inputreader = null;
            input = null;
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public Handler handler = new Handler() {
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            refresh();
        }
    };

    public void run() {
        // TODO Auto-generated method stub
        while (true) {
            try {
                Thread.sleep(1000);
                handler.sendMessage(handler.obtainMessage());
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}