src/main/java/com/authlete/jaxrs/AuthleteApiCaller.java
public InternalServerErrorException unknownAction(String path, Enum<?> action)
    {
        // Error message.
        String message = String.format("Authlete %s API returned an unknown action: %s", path, action);

        // 500 Internal Server Error
        return internalServerError(message, null);
    }
public InternalServerErrorException unknownAction(String path, Enum<?> action)
    {
        // Error message.
        String message = String.format("Authlete %s API returned an unknown action: %s", path, action);

        // 500 Internal Server Error
        return internalServerError(message, null);
    }
Create an {@link InternalServerErrorException} instance to indicate
that the value of {@code action} parameter contained in a response
from an Authlete API is unknown.