code: public boolean respondToDisconnect(int statusCode, String reasonPhrase) {
      initErrorInfo();
      if (parent.sendReply(transaction, statusCode, reasonPhrase, myTag, null, -1) != null) {
        return true;
      }
  
      setReturnCode(parent.getReturnCode());
      setException(parent.getException());
      setErrorMessage("respondToDisconnect() - " + parent.getErrorMessage());
  
      return false;
    }
docs: This method is the same as the basic respondToDisconnect() method except that it uses the given
  parameters for the status code and reason in the response message sent out.
  
  @param statusCode The integer status code to use (ie, SipResponse.OK).
  @param reasonPhrase The String reason phrase to use.
  @return true if the response was successfully sent, false otherwise.