docs: @Override
      public void deleteLink(String name1, String name2, String... domain) {
          if (domain.length == 1) {
              name1 = domain[0] + "::" + name1;
              name2 = domain[0] + "::" + name2;
          } else if (domain.length > 1) {
              throw new Error("error: domain should be 1 parameter");
          }
  
          if (!hasRole(name1) || !hasRole(name2)) {
              throw new Error("error: name1 or name2 does not exist");
          }
  
          Role role1 = createRole(name1);
          Role role2 = createRole(name2);
          role1.deleteRole(role2);
      }