java .lang. StringIndexOutOfBounds Exception

This is my code

public class MainActivity extends ActionBarActivity {

String seedValue = "MAKV2SPBNI99212";
String device,json;
String DeviceID = "490154203237518";
String ControllerDeviceID = "Null";
String PartnerMode = "None";
String PhoneModel="Samsung";
String PhoneNumber = "8056792232";
String PhoneOS = "Lollypop";
String CreatedOn = "15.02.1201";
String Status = "Active";

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//// String seedValue = "MAKV2SPBNI99212";
// String normalText = "VIJAY";
// String normalTextEnc;
//// String Json="";
JSONObject jsonObject = new JSONObject();
try {
JSONObject jsonObject1=new JSONObject();
jsonObject1.accumulate("DeviceId",DeviceID);
jsonObject1.accumulate("ControllerDeviceID",ControllerDeviceID);
jsonObject1.accumulate("PartnerMode",PartnerMode);
jsonObject1.accumulate("PhoneModel",PhoneModel);
jsonObject1.accumulate("PhoneNumber",PhoneNumber);
jsonObject1.accumulate("PhoneOS",PhoneOS);
jsonObject1.accumulate("CreatedOn",CreatedOn);
jsonObject1.accumulate("Status",Status);
json=jsonObject1.toString();

} catch (JSONException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
try {
device = AESHelper.encrypt(seedValue,json);
String normalTextDec = AESHelper.decrypt(seedValue,device);
TextView txe=(TextView)findViewById(R.id.textView);
txe.setTextSize(14);
txe.setText("Normal Text ::"+json +" \n Encrypted Value :: "+device +" \n Decrypted value :: "+normalTextDec);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Encryption ex=new Encryption();
ex.execute();
}
class Encryption extends AsyncTask
{
@Override
protected Object doInBackground(Object[] params) {
Httpt();
return null;
}
public void Httpt()
{
HttpPost httpPost1=new HttpPost("http://kredo.no-ip.org/SSMA/api/DevicesAPI/RegisterDevice?device="+device);
try {

HttpClient httpClient=new DefaultHttpClient();
HttpResponse response=httpClient.execute(httpPost1);
HttpEntity entity = response.getEntity();
String responseBody = EntityUtils.toString(entity); //To receive response from server
Log.v("response", responseBody.toString());

} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

}
}
}