public void onVarData(final Token token)
        {
            if (filter.test(token))
            {
                final CodecInteraction lengthAccessInteraction = interactionFactory.accessVarDataLength(token);
                currentStates.forEach(
                    (state) -> allocateTransitions(lengthAccessInteraction, Collections.singleton(state), state));

                final CodecInteraction codecInteraction = interactionFactory.accessField(token);
                final State accessedState = allocateState(statePrefix + token.name().toUpperCase() + "_DONE");
                allocateTransitions(codecInteraction, currentStates, accessedState);
                currentStates.clear();
                currentStates.add(accessedState);
            }
        }
Encodes the state machine as a graphviz dot diagram.
@param sb the string builder to append to.
@param indent the indentation to use.
sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/common/FieldPrecedenceModel.java