code: public Set<Integer> removeConnections(String endpointId) {
          Set<Integer> removed = this.entries.removeAll(endpointId);
          if (!removed.isEmpty() && log.isDebugEnabled()) {
              log.debug("Call " + getCallIdHex() + " unregistered connections " + Arrays.toString(convertToHex(removed)) + " from endpoint " + endpointId);
          }
          return removed;
      }
docs: Unregisters all connections that belong to an endpoint.
  
  @param endpointId The identifier of the endpoint that owns the connections.
  @return A set containing all unregistered connection identifiers. Returns an empty set if no connections exist.