class InMemoryUserMaster extends AbstractInMemoryMaster<ManageableUser> implements UserMaster {

  @Override
  public ManageableUser getByName(String userName) {
    ArgumentChecker.notNull(userName, "userName");
    return super.getByName(userName);
  }

  public  InMemoryUserMaster();
  public  InMemoryUserMaster(final ObjectIdSupplier objectIdSupplier);
  public  InMemoryUserMaster(final ObjectIdSupplier objectIdSupplier, final ChangeManager changeManager);

}