@Override
    public TristateResult hasPermission(String permission) {
        Tristate t = this.plugin.getDefaultPermissionMap().lookupDefaultPermission(permission, this.isOp);
        if (t != Tristate.UNDEFINED) {
            return RESULT_FACTORY.result(t);
        }

        return TristateResult.UNDEFINED;
    }
Permission Processor for Bukkits "default" permission system.
bukkit/src/main/java/me/lucko/luckperms/bukkit/calculator/DefaultPermissionMapProcessor.java