ServicesManager sm = Bukkit.getServicesManager();
Permission p = sm.getRegistration(Permission.class).getProvider();
List<String> result = new ArrayList<String>();
for (org.bukkit.permissions.Permission perm : Bukkit.getPluginManager().getPermissions()) {
String permName = perm.getName();
if (p.groupHas(Bukkit.getWorlds().get(0), groupName, permName)) {
result.add(permName);
}
}
return result;
}