android - バックグラウンド サービスで実行時エラーが受信トレイ メッセージを読み取る

Question

バックグラウンドサービスの受信トレイで未読のSMSを読み取ろうとしていますが、SMSを読み取っていますが、実行時にSMSを読み取った後にforceCloseを取得しています。

public class MyService extends Service {
private static final String TAG = "MyService";
MediaPlayer player;
Context context;
String value="";
int flag;
int unreadMessagesCount;
@Override
public void onCreate() {
    Log.d(TAG, "onCreate");
    player = MediaPlayer.create(this, R.raw.gossip_blast);
    player.setVolume(50,50);
    Toast.makeText(this, "My Service Created", Toast.LENGTH_LONG).show();
    final Uri SMS_INBOX = Uri.parse("content://sms/inbox");
    Cursor c = getContentResolver().query(SMS_INBOX, null, "read = 0", null, null);
    unreadMessagesCount = c.getCount();
    String cnt=Integer.toString(unreadMessagesCount);
    String val="";
    while(c.moveToNext())
            {
    value= c.getString(c.getColumnIndex("body"));
        val=val+ c.getString(c.getColumnIndex("body"))+"\n";
        if(value.indexOf("help")>0)
        {
        Toast.makeText(this,"HELP", Toast.LENGTH_LONG).show();
        player.start();
           // Vibrator vibrator = (Vibrator) context.getSystemService(Context.VIBRATOR_SERVICE);
            //vibrator.vibrate(2000);
            String notificationService = Context.NOTIFICATION_SERVICE;
            NotificationManager notificationManager = (NotificationManager) getSystemService(notificationService);          
            Notification notification = new Notification(R.drawable.images,value, System.currentTimeMillis());
            Intent notificationIntent = new Intent(getApplicationContext(), DaySixteenActivity.class);
            PendingIntent contentIntent = PendingIntent.getActivity(getApplicationContext(), 0,notificationIntent, 0);
            notification.setLatestEventInfo(getApplicationContext(), value, value,contentIntent);
            notificationManager.notify(1, notification);
            }
    }
    c.deactivate();
    c.close();      
}
    public void startAlert(View view) {         
        Intent intent = new Intent(this, read_sms.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(this.getApplicationContext(), 234324243, intent, 0);           
        Toast.makeText(this, "Alarm set in  " ,
            Toast.LENGTH_LONG).show();
      } 
    @Override
    public void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        Toast.makeText(this, "My Service Stopped", Toast.LENGTH_LONG).show();
        Log.d(TAG, "onDestroy");
    }
@Override
public void onStart(Intent intent, int startid) {
    Toast.makeText(this, "My Service Started", Toast.LENGTH_LONG).show();
    Log.d(TAG, "onStart");  
    }
    @Override
public IBinder onBind(Intent intent)
    {
    return null;
}    }

このエラーが発生する

04-23 11:36:55.719: E/AndroidRuntime(7509): FATAL EXCEPTION: main
04-23 11:36:55.719: E/AndroidRuntime(7509): java.lang.RuntimeException: Unable to  instantiate service com.example.MyService: java.lang.NullPointerException
04-23 11:36:55.719: E/AndroidRuntime(7509):     at android.app.ActivityThread.handleCreateService(ActivityThread.java:2388)
04-23 11:36:55.719: E/AndroidRuntime(7509):     at android.app.ActivityThread.access$1600(ActivityThread.java:140)
04-23 11:36:55.719: E/AndroidRuntime(7509):     at dalvik.system.NativeStart.main(Native Method)
04-23 11:36:55.719: E/AndroidRuntime(7509): Caused by: java.lang.NullPointerException
04-23 11:36:55.719: E/AndroidRuntime(7509):     at android.content.ContextWrapper.getContentResolver(ContextWrapper.java:91)
04-23 11:36:55.719: E/AndroidRuntime(7509):     at java.lang.Class.newInstanceImpl(Native Method)

マニフェスト ファイルにアクセス許可を含めました

<uses-permission android:name="android.permission.READ_SMS" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.RECEIVE_SMS" />
<service android:enabled="true" android:name=".MyService" />
      <receiver android:name=".MyService" android:exported="true">
            <intent-filter android:priority="999" >
                <action android:name="android.intent.action.PHONE_STATE" />
                <action android:name="android.provider.Telephony.SMS_RECEIVED" />                                     
            </intent-filter>
        </receiver>