code: @Override
    public Collection<Realm> removeRealm(String realmName) {
      RealmSet set = null;
      if (realmName.equals(this.localRealmName)) {
        set = this.realmNameToRealmSet.get(realmName);
      }
      else {
        set = this.realmNameToRealmSet.remove(realmName);
        if (set != null) {
          Collection<Realm> present = set.values();
          allRealmsSet.remove(realmName);
          return new ArrayList<Realm>(present);
        }
      }
  
      return null;
    }
docs: /*
  (non-Javadoc)
  @see org.jdiameter.client.api.controller.IRealmTable#removeRealms(java.lang.String)