gistfile1.txt

package ai.cbx1.commons.statemachine;

// This class gives out methods to take in a list of transitions and turn it into a .dot file
// you can use any online digraph visualiser to see the output 

import static guru.nidi.graphviz.model.Factory.*;

import guru.nidi.graphviz.attribute.*;
import guru.nidi.graphviz.model.MutableGraph;
import guru.nidi.graphviz.model.MutableNode;
import java.util.HashMap;
import java.util.Map;
import org.springframework.statemachine.StateMachine;
import org.springframework.statemachine.state.State;
import org.springframework.statemachine.transition.Transition;

public class StateMachineVisualiser<S, E> {
    public String getDiagram(StateMachine<S, E> stateMachine, String graphName) {
        MutableGraph graph = mutGraph(graphName)
                .setDirected(true)
                .graphAttrs()
                .add(
                        Attributes.attr("rankdir", "LR"),
                        Attributes.attr("nodesep", "1.0"),
                        Attributes.attr("ranksep", "1.2"),
                        Attributes.attr("pad", "0.5"),
                        Attributes.attr("fontname", "helvetica"));

        Map<S, MutableNode> nodes = new HashMap<>();

        for (State<S, E> state : stateMachine.getStates()) {
            MutableNode node = mutNode(state.getId().toString());
            if (state.getId().equals(stateMachine.getInitialState().getId())) {
                node.add(Shape.RECTANGLE).add(Color.LIGHTBLUE).add(Style.ROUNDED);
            }
            nodes.put(state.getId(), node);
            graph.add(node);
        }

        for (Transition<S, E> transition : stateMachine.getTransitions()) {
            MutableNode source = nodes.get(transition.getSource().getId());
            MutableNode target = nodes.get(transition.getTarget().getId());
            E event = transition.getTrigger().getEvent();
            source.addLink(to(target).with(Label.of(event.toString()), Style.SOLID, Color.GREEN, Font.size(10)));
        }
        return graph.toString();
    }
}