private static boolean isExternalStorageReadOnly() {

String externalStorageState = Environment.getExternalStorageState();

return Environment.MEDIA_MOUNTED_READ_ONLY.equals(externalStorageState);

}

private static boolean isExternalStorageAvailable() {

String externalStorageState = Environment.getExternalStorageState();

return Environment.MEDIA_MOUNTED.equals(externalStorageState);

}