if(Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1) {
    boolean hasPermission = checkSelfPermission(Manifest.permission.XX)
                == PackageManager.PERMISSION_GRANTED;
    if(!hasPermission) {
        if(shouldShowRequestPermissionRationale(Manifest.permission.XX)) {
            // explain reason for permission, try again

        } else {
            // user deny with "don't show again"
        }
    }
}