presto-client/src/main/java/io/prestosql/client/Warning.java/Warning/Warning
class Warning:    @JsonCreator
    public Warning(
            @JsonProperty("warningCode") Code warningCode,
            @JsonProperty("message") String message)
    {
        this.warningCode = requireNonNull(warningCode, "warningCode is null");
        this.message = requireNonNull(message, "message is null");
    }