public java.util.List<ClientVpnAuthenticationRequest> getAuthenticationOptions() {
        if (authenticationOptions == null) {
            authenticationOptions = new com.amazonaws.internal.SdkInternalList<ClientVpnAuthenticationRequest>();
        }
        return authenticationOptions;
    }
<p>
Information about the authentication method to be used to authenticate clients.
</p>

@return Information about the authentication method to be used to authenticate clients.
aws-java-sdk-ec2/src/main/java/com/amazonaws/services/ec2/model/CreateClientVpnEndpointRequest.java