Android : how to get mobile number from my current Phone? it's display blank Mobile Number in Log. but when run on emulator its display emulator Number

public class MobileNumber extends Activity {

TextView mobNO;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.mobile_number);
    mobNO = (TextView) findViewById(R.id.txtMobNO);

    TelephonyManager tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
    String getSimSerialNumber = tm.getSimSerialNumber();
    String getOperatorName = tm.getSimOperatorName();
    String getNetworkCountry = tm.getNetworkCountryIso();
    String getDeviceSoftVersion = tm.getDeviceSoftwareVersion();
    String getDeviceId = tm.getDeviceId();

    if (tm.getSimState() != TelephonyManager.SIM_STATE_ABSENT) {

        String mPhoneNumber = tm.getLine1Number();

        String mobilenumber = mPhoneNumber.substring(Math.max(
                mPhoneNumber.length() - 10, 0));

        Log.e("My Number is:-", "-------" + "  " + mobilenumber);
        Log.e("My Operator Name is:- ", "*******" + "  " + getOperatorName);
        Log.e("My Sim is:-", "******* " + "  " + getSimSerialNumber);
        Log.e("My Network Country is:-", "*******" + "  "
                + getNetworkCountry);
        Log.e("My Device Software Version:-", "*******" + "  "
                + getDeviceSoftVersion);
        Log.e("My Device Id is.:-", "-------" + "  " + getDeviceId);

        mobNO.setText(mobilenumber);

    } else {

        Log.e("no sim card", "...");

    }

}

}

--------------------------------------------OUTPUT---------------------------------------------------- 09-08 14:17:24.618: E/My Number is:-(1206): ------- 09-08 14:17:24.618: E/My Operator Name is:-(1206): * Android 09-08 14:17:24.618: E/My Sim is:-(1206): * 89014103211118510720 09-08 14:17:24.618: E/My Network Country is:-(1206): * us 09-08 14:17:24.618: E/My Device Software Version:-(1206): * null 09-08 14:17:24.618: E/My Device Id is.:-(1206): ------- 000000000000000