1 package com.example.downloadtext; 2  3 import android.app.Activity; 4 import android.os.Bundle; 5 import android.os.Environment; 6 import android.util.Log; 7 import android.view.View; 8 import android.widget.Button; 9 import android.widget.Toast;10 11 import java.io.File;12 import java.io.IOException;13 import java.net.HttpURLConnection;14 15 public class MyActivity extends Activity16     {17     /**18      * Called when the activity is first created.19      */20     static String sdcardpath = "/storage/sdcard/";21     Button download;22 23     @Override24     public void onCreate(Bundle savedInstanceState)25         {26         super.onCreate(savedInstanceState);27         setContentView(R.layout.main);28         download = (Button) findViewById(R.id.download);29         download.setOnClickListener(new downloadListener());30 31 32         }33 34 35     class downloadListener implements View.OnClickListener36     {37         @Override38 39         public void onClick(View view)40         {   Log.v("button","button has been clicked");41              42             new DownloadThread().start();43             File file = new File(sdcardpath + "song");44             if (file.exists())45                 {46                 Toast.makeText(MyActivity.this, "download Sucess", Toast.LENGTH_LONG);//toast只能在ui进程中才能显示，所以这些都不能显示47 48                  }49             else50                  {51                 Toast.makeText(MyActivity.this, "download failed", Toast.LENGTH_LONG);52 53                  }54 55         }56 57 58     }59 60     class DownloadThread extends Thread61     {62         @Override63         public void run() {64             Log.v("thread","new thread is started");65             Download downloadmp3 = new Download();66             try67                 {68                 downloadmp3.downloadmp3("http://sc.111ttt.com/up/mp3/276964/2684CCF02022F454B9E67B5D35F9DDF0.mp3");69                 }70             catch (IOException e)71                 {72                 e.printStackTrace();73                 }74                 Log.v("thread","thread is overed");75         }76     }77 }
Download类

package com.example.downloadtext;import java.io.*;import java.net.HttpURLConnection;import java.net.URL;import java.nio.Buffer;import java.nio.ByteBuffer;/** * Created by Administrator on 2014/8/14. */public class Download {    public void downloadmp3(String urlpath)throws IOException    {        URL url = new URL(urlpath);        HttpURLConnection urlconnection = (HttpURLConnection) url.openConnection();        InputStream inputStream = urlconnection.getInputStream();        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));        FileOutputStream fos = new FileOutputStream(new File(MyActivity.sdcardpath+"song"));        String readed;        while((readed =reader.readLine() )!=null)        {            fos.write(readed.getBytes());        }        fos.close();        inputStream.close();     } }