/**
   * Get the remote phone number involved in the current call
   *
   * @return Phone number or null if there is no call in progress
   * @throws ServerApiException
   */
  public String getRemotePhoneNumber() throws ServerApiException {
    if (logger.isActivated()) {
      logger.info("Get remote phone number");
    }

    // Test core availability
    ServerApiUtils.testCore();

    try {
      return Core.getInstance().getImsModule().getCallManager().getRemoteParty();
    } catch (Exception e) {
      if (logger.isActivated()) {
        logger.error("Unexpected error", e);
      }
      throw new ServerApiException(e.getMessage());
    }
  }