public void execute(String[] parameterList, Connection connection, User user, FileSystem fs) {
if (user.hasPermission(UserPermission.GROUPS)) { // gadmins can't add EXISTING users to their groups
try {
User u = ServiceManager.getServices().getUserbase().getUser(parameterList[1]);
ServiceManager.getServices().getUserbase().getGroup(parameterList[2]); // this is done to verify that the group exists
u.addGroup(parameterList[2]);
connection.respond("200 sucessfully added user " + parameterList[1] + " to group " + parameterList[2] + '.');
} catch (NoSuchUserException e) {
connection.respond("500 " + e.getMessage());
} catch (NoSuchGroupException e) {
connection.respond("500 " + e.getMessage());