private static DocapiFeed.TestAndSetCondition toProtoTasCondition(TestAndSetCondition tasCond) {
        var builder = DocapiFeed.TestAndSetCondition.newBuilder();
        if (!tasCond.getSelection().isEmpty()) {
            builder.setSelection(tasCond.getSelection());
        }
        if (tasCond.requiredTimestamp() != 0) {
            builder.setRequiredTimestamp(tasCond.requiredTimestamp());
        }
        return builder.build();
    }
Implementation of MessageBus message request/response serialization built around Protocol Buffers.
documentapi/src/main/java/com/yahoo/documentapi/messagebus/protocol/RoutableFactories80.java