*/
    public void setUsername(final String userName) {
        this.username = userName;
    }

    /**
     * Get the passphrase of the private key file. The passphrase is used only when host/protocol supports
     * authentication via exchange of private/public keys and private key was used for authentication.
     *
     * @return passphrase of the private key file
     */
    public String getPassphrase() {