title: mediaPlayer prepare nullpointer exception
body: <p>it's realy rare error for me but.. It's error. Can't understand why. 
  error just on line </p>
  
  <pre><code>mp.prepare();
  </code></pre>
  
  <p>from logcat :</p>
  
  <pre><code>  Caused by: java.lang.NullPointerException
              at myapp.activity.com.myApp.media(myApp.java:281)
              at myapp.activity.com.myApp$showLogotype.doInBackground(myApp.java:397)
              at myapp.activity.com.myApp$showLogotype.doInBackground(myApp.java:1)
              at android.os.AsyncTask$2.call(AsyncTask.java:185)
              at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305
  </code></pre>
  
  <p>Someone can explain me :( ?</p>
  
  <p>Im using  asynctask for prepare and load all datas and showing logo while my app reading datas and preparing for mediaPlayer( in logcat : mediaPlayer.prepare() getting 5-10 seconds) )
  But im sometimes have this realy rare error for me(cos i can't understand how to get this error and he is realy rare for me)</p>
  
  <p>Please explain me if anyone know :( or please&lt; tell me how to fix this  :(
  code of function :</p>
  
  <pre><code> public void media() throws IllegalArgumentException, IllegalStateException, IOException
      {
  
          mp = new MediaPlayer();
          mp.setDataSource(stream);
          mp.prepare();
  
      }
  </code></pre>
  
  <p>Regards,Peter. Sorry for my bad english, hope u understand me  </p>