android 开发视频播放器的时候报这样的错是怎么回事啊？在线等

Question

这是源码public class MainActivity extends Activity  implements OnClickListener{
    /** Called when the activity is first created. */
private MediaPlayer mediaPlayer=new MediaPlayer();
private SurfaceView sfView;
private LinearLayout llBar;

//是否在播放
private boolean requirePlay=false;
//当前播放位置
private int currPos;
    @Override
    public void onCreate(Bundle savedInstanceState) {
    
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        findViewById(R.id.btnPlay).setOnClickListener(this);
        findViewById(R.id.btnStop).setOnClickListener(this);
        sfView=(SurfaceView)findViewById(R.id.svView);
        llBar=(LinearLayout)findViewById(R.id.ll_Bar);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        sfView.getHolder().setFixedSize(100, 144);
        sfView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        sfView.getHolder().addCallback(new Callback(){
         //销毁
         public void surfaceDestroyed(SurfaceHolder holder){
        
         }
         //创建
         public void surfaceCreated(SurfaceHolder holder){
         if(requirePlay){
         play();
         //定位到指定时间段
         mediaPlayer.seekTo(currPos);
         }
         }
         //改变
         public void surfaceChanged(SurfaceHolder holder,int format,int width,int height){
        
         }
        });
    }
    public void onClick(View v){
     int id=v.getId();
     //开始播放
     if(id==R.id.btnPlay){
     play();
     }
     //停止播放
     else if(id==R.id.btnStop){
     mediaPlayer.stop();
     requirePlay=false;
     }
    }
    /**
     播放
     */
    private void play(){
     try{
     requirePlay=true;
     //重置为初始状态
     mediaPlayer.reset();
     //设置音频为流类型
     mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
     //设置页面输出
     mediaPlayer.setDisplay(sfView.getHolder());
     //设置文件路径
     String path="http://flv.aedu.co/index.aspx?file=004";
     if(Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())){
     path=Environment.getExternalStorageDirectory()+"/youku.3gp";
     }else{
     Toast.makeText(this, "文件挂载问题", Toast.LENGTH_LONG).show();
     return;
     }
     mediaPlayer.setDataSource(path);
     mediaPlayer.prepare();
     mediaPlayer.start();
     llBar.setVisibility(View.GONE);
     }catch(Exception e){
     e.printStackTrace();
     }
    }
    /**
     暂停
     */
    protected void onPause(){
     super.onPause();
     if(mediaPlayer.isPlaying()){
     currPos=mediaPlayer.getCurrentPosition();
     mediaPlayer.stop();
     requirePlay=true;
     }
    }
    /**
     销毁
     */
    protected void onDestroy(){
     super.onDestroy();
     mediaPlayer.release();
    }
    public boolean onKeyDown(int keyCode,KeyEvent event){
     if(keyCode==KeyEvent.KEYCODE_SEARCH){
     llBar.setVisibility(View.VISIBLE);
     }
     return true;
    }
}
这是报的错误
11-06 06:59:38.821: E/MediaPlayer(765): error (1, -2147483648)
11-06 06:59:38.832: W/System.err(765): java.io.IOException: Prepare failed.: status=0x1
11-06 06:59:38.832: W/System.err(765):  at android.media.MediaPlayer.prepare(Native Method)
11-06 06:59:38.841: W/System.err(765):  at My.Videos.MainActivity.play(MainActivity.java:94)
11-06 06:59:38.841: W/System.err(765):  at My.Videos.MainActivity.onClick(MainActivity.java:63)
11-06 06:59:38.841: W/System.err(765):  at android.view.View.performClick(View.java:2408)
11-06 06:59:38.841: W/System.err(765):  at android.view.View$PerformClick.run(View.java:8816)
11-06 06:59:38.841: W/System.err(765):  at android.os.Handler.handleCallback(Handler.java:587)
11-06 06:59:38.851: W/System.err(765):  at android.os.Handler.dispatchMessage(Handler.java:92)
11-06 06:59:38.851: W/System.err(765):  at android.os.Looper.loop(Looper.java:123)
11-06 06:59:38.851: W/System.err(765):  at android.app.ActivityThread.main(ActivityThread.java:4627)
11-06 06:59:38.851: W/System.err(765):  at java.lang.reflect.Method.invokeNative(Native Method)
11-06 06:59:38.851: W/System.err(765):  at java.lang.reflect.Method.invoke(Method.java:521)
11-06 06:59:38.851: W/System.err(765):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
11-06 06:59:38.861: W/System.err(765):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
11-06 06:59:38.861: W/System.err(765):  at dalvik.system.NativeStart.main(Native Method)