private void handlePreDecodeException(
            ServiceRequestContext ctx, CompletableFuture<HttpResponse> httpRes, Throwable cause,
            SerializationFormat serializationFormat, int seqId, String methodName) {

        final HttpData content = encodeException(
                ctx, RpcResponse.ofFailure(cause), serializationFormat, seqId, methodName, cause);
        respond(serializationFormat, content, httpRes);
    }
Returns the default {@link SerializationFormat} of this service.
thrift/thrift0.13/src/main/java/com/linecorp/armeria/server/thrift/THttpService.java