Add support for submachine refs

- Relates to #262

spring-statemachine-data/jpa/src/main/java/org/springframework/statemachine/data/jpa/JpaRepositoryState.java

@@ -51,6 +51,7 @@ public class JpaRepositoryState extends RepositoryState {
 	private String region;
 	private boolean initial;
 	private PseudoStateKind kind;
+	private String submachineId;
 
 	@OneToOne(fetch = FetchType.EAGER)
 	private JpaRepositoryState parentState;
@@ -227,11 +228,20 @@ public class JpaRepositoryState extends RepositoryState {
 		this.deferredEvents = deferredEvents;
 	}
 
+	@Override
+	public String getSubmachineId() {
+		return submachineId;
+	}
+
+	public void setSubmachineId(String submachineId) {
+		this.submachineId = submachineId;
+	}
+
 	@Override
 	public String toString() {
 		return "JpaRepositoryState [id=" + id + ", machineId=" + machineId + ", state=" + state + ", region=" + region
-				+ ", initial=" + initial + ", kind=" + kind + ", parentState=" + parentState + ", stateActions="
-				+ stateActions + ", entryActions=" + entryActions + ", exitActions=" + exitActions + ", deferredEvents="
-				+ deferredEvents + "]";
+				+ ", initial=" + initial + ", kind=" + kind + ", submachineId=" + submachineId + ", parentState="
+				+ parentState + ", stateActions=" + stateActions + ", entryActions=" + entryActions + ", exitActions="
+				+ exitActions + ", deferredEvents=" + deferredEvents + "]";
 	}
 }

spring-statemachine-data/jpa/src/test/java/org/springframework/statemachine/data/jpa/JpaRepositoryTests.java

@@ -515,6 +515,25 @@ public class JpaRepositoryTests extends AbstractJpaRepositoryTests {
 		plan.test();
 	}
 
+	@SuppressWarnings("unchecked")
+	@Test
+	public void testMachine13() throws Exception {
+		context.register(Config13.class, FactoryConfig.class);
+		context.refresh();
+		StateMachineFactory<String, String> stateMachineFactory = context.getBean(StateMachineFactory.class);
+		StateMachine<String, String> stateMachine = stateMachineFactory.getStateMachine();
+
+		StateMachineTestPlan<String, String> plan =
+				StateMachineTestPlanBuilder.<String, String>builder()
+					.stateMachine(stateMachine)
+					.step().expectStates("S1").and()
+					.step().sendEvent("E1").expectStates("S2", "S21").and()
+					.step().sendEvent("E3").expectStates("S2", "S22").and()
+					.step().sendEvent("E2").expectStates("S3").and()
+					.build();
+		plan.test();
+	}
+
 	@Test
 	public void testPopulate1() {
 		context.register(Config2.class);
@@ -729,6 +748,17 @@ public class JpaRepositoryTests extends AbstractJpaRepositoryTests {
 		}
 	}
 
+	@EnableAutoConfiguration
+	static class Config13 {
+
+		@Bean
+		public StateMachineJackson2RepositoryPopulatorFactoryBean jackson2RepositoryPopulatorFactoryBean() {
+			StateMachineJackson2RepositoryPopulatorFactoryBean factoryBean = new StateMachineJackson2RepositoryPopulatorFactoryBean();
+			factoryBean.setResources(new Resource[]{new ClassPathResource("data13.json")});
+			return factoryBean;
+		}
+	}
+
 	@Configuration
 	@EnableStateMachineFactory
 	public static class FactoryConfig extends StateMachineConfigurerAdapter<String, String> {

spring-statemachine-data/jpa/src/test/resources/data13.json

@@ -0,0 +1,50 @@
+[
+	{
+		"@id": "1",
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryState",
+		"initial": true,
+		"state": "S1"
+	},
+	{
+		"@id": "2",
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryState",
+		"submachineId": "machineS2",
+		"state": "S2"
+	},
+	{
+		"@id": "3",
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryState",
+		"state": "S3"
+	},
+	{
+		"@id": "4",
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryState",
+		"machineId": "machineS2",
+		"initial": true,
+		"state": "S21"
+	},
+	{
+		"@id": "5",
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryState",
+		"machineId": "machineS2",
+		"state": "S22"
+	},
+	{
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryTransition",
+		"source": "1",
+		"target": "2",
+		"event": "E1"
+	},
+	{
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryTransition",
+		"source": "2",
+		"target": "3",
+		"event": "E2"
+	},
+	{
+		"_class": "org.springframework.statemachine.data.jpa.JpaRepositoryTransition",
+		"source": "4",
+		"target": "5",
+		"event": "E3"
+	}
+]

spring-statemachine-data/src/main/java/org/springframework/statemachine/data/RepositoryState.java

@@ -96,4 +96,12 @@ public abstract class RepositoryState extends BaseRepositoryEntity {
 	 * @return the deferred events
 	 */
 	public abstract Set<String> getDeferredEvents();
+
+	/**
+	 * Gets the submachine id indicating that this is a submachine state
+	 * and its structure is available from particular machine itself.
+	 *
+	 * @return the submachine id
+	 */
+	public abstract String getSubmachineId();
 }

spring-statemachine-data/src/main/java/org/springframework/statemachine/data/RepositoryStateMachineModelFactory.java

@@ -85,6 +85,13 @@ public class RepositoryStateMachineModelFactory extends AbstractStateMachineMode
 		Collection<StateData<String, String>> stateDatas = new ArrayList<>();
 		for (RepositoryState s : stateRepository.findByMachineId(machineId)) {
 
+			// do recursive build to get states for a submachine
+			StateMachineModel<String, String> subStateMachineModel = null;
+			String submachineId = s.getSubmachineId();
+			if (submachineId != null) {
+				subStateMachineModel = build(submachineId);
+			}
+
 			Collection<Action<String, String>> stateActions = new ArrayList<Action<String, String>>();
 			Set<? extends RepositoryAction> repositoryStateActions = s.getStateActions();
 			if (repositoryStateActions != null) {
@@ -156,6 +163,18 @@ public class RepositoryStateMachineModelFactory extends AbstractStateMachineMode
 				}
 			}
 			stateData.setDeferred(s.getDeferredEvents());
+
+			if (subStateMachineModel != null) {
+				// copy are set parent as state we're currently on
+				Collection<StateData<String, String>> submachineStateData = new ArrayList<>();
+				Collection<StateData<String, String>> submachineStateDataOrig = subStateMachineModel.getStatesData().getStateData();
+				for (StateData<String, String> sd : submachineStateDataOrig) {
+					submachineStateData.add(new StateData<String, String>(s.getState(), sd.getRegion(), sd.getState(),
+							sd.getDeferred(), sd.getEntryActions(), sd.getExitActions(), sd.isInitial()));
+				}
+				stateData.setSubmachineStateData(submachineStateData);
+			}
+
 			stateDatas.add(stateData);
 		}
 		StatesData<String, String> statesData = new StatesData<>(stateDatas);