Direct region entry doesn't bypass initial state entry

- Enhance state context to have more info about target
  states which is needed to make a proper decision if
  region needs to be started.
- Fix RegionState to not to start if it looks like
  direct entry will be done later.
- Relates to #221

spring-statemachine-core/src/main/java/org/springframework/statemachine/StateContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,6 +15,8 @@
  */
 package org.springframework.statemachine;
 
+import java.util.Collection;
+
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageHeaders;
 import org.springframework.statemachine.action.Action;
@@ -104,7 +106,17 @@ public interface StateContext<S, E> {
 	 *
 	 * @return the source state
 	 */
-	State<S,E> getSource();
+	State<S, E> getSource();
+
+	/**
+	 * Gets the source states of this context. Multiple sources are
+	 * only valid during a context when machine is joining from multiple
+	 * orthogonal regions.
+	 *
+	 * @return the source state
+	 * @see #getSource()
+	 */
+	Collection<State<S, E>> getSources();
 
 	/**
 	 * Gets the target state of this context. Generally target
@@ -113,7 +125,17 @@ public interface StateContext<S, E> {
 	 *
 	 * @return the target state
 	 */
-	State<S,E> getTarget();
+	State<S, E> getTarget();
+
+	/**
+	 * Gets the target states of this context. Multiple targets are
+	 * only valid during a context when machine is forking into multiple
+	 * orthogonal regions.
+	 *
+	 * @return the target states
+	 * @see #getTarget()
+	 */
+	Collection<State<S, E>> getTargets();
 
 	/**
 	 * Gets the exception associated with a context.
@@ -138,5 +160,4 @@ public interface StateContext<S, E> {
 		TRANSITION_START,
 		TRANSITION_END;
 	}
-
 }

spring-statemachine-core/src/main/java/org/springframework/statemachine/state/RegionState.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,7 +17,6 @@ package org.springframework.statemachine.state;
 
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.List;
 
 import org.springframework.messaging.Message;
 import org.springframework.statemachine.StateContext;
@@ -159,14 +158,8 @@ public class RegionState<S, E> extends AbstractState<S, E> {
 		if (getPseudoState() != null && getPseudoState().getKind() == PseudoStateKind.INITIAL) {
 			for (Region<S, E> region : getRegions()) {
 				boolean start = true;
-				PseudoState<S, E> ps = context.getTransition().getTarget().getPseudoState();
-				if (ps != null && ps.getKind() == PseudoStateKind.FORK) {
-					List<State<S, E>> forks = ((ForkPseudoState<S, E>)ps).getForks();
-					if (StateMachineUtils.containsAtleastOne(region.getStates(), forks)) {
-						// it looks like fork will take directly into a state so don't start
-						// as we want to bypass initial entry logic.
-						start = false;
-					}
+				if (StateMachineUtils.containsAtleastOne(region.getStates(), context.getTargets())) {
+					start = false;
 				}
 				if (start) {
 					region.start();

spring-statemachine-core/src/main/java/org/springframework/statemachine/support/AbstractStateMachine.java

@@ -735,7 +735,7 @@ public abstract class AbstractStateMachine<S, E> extends StateMachineObjectSuppo
 			ForkPseudoState<S, E> fps = (ForkPseudoState<S, E>) toState.getPseudoState();
 			for (State<S, E> ss : fps.getForks()) {
 				callPreStateChangeInterceptors(ss, message, transition, stateMachine);
-				setCurrentState(ss, message, transition, false, stateMachine);
+				setCurrentState(ss, message, transition, false, stateMachine, null, fps.getForks());
 			}
 		} else {
 			setCurrentState(toState, message, transition, true, stateMachine);
@@ -811,6 +811,12 @@ public abstract class AbstractStateMachine<S, E> extends StateMachineObjectSuppo
 		return new DefaultStateContext<S, E>(stage, message, messageHeaders, extendedState, transition, stateMachine, source, target, null);
 	}
 
+	private StateContext<S, E> buildStateContext(Stage stage, Message<E> message, Transition<S,E> transition, StateMachine<S, E> stateMachine, Collection<State<S, E>> sources, Collection<State<S, E>> targets) {
+		MessageHeaders messageHeaders = message != null ? message.getHeaders() : new MessageHeaders(
+				new HashMap<String, Object>());
+		return new DefaultStateContext<S, E>(stage, message, messageHeaders, extendedState, transition, stateMachine, null, null, sources, targets, null);
+	}
+
 	private State<S, E> findDeepParent(State<S, E> state) {
 		for (State<S, E> s : states) {
 			if (s.getStates().contains(state)) {
@@ -821,6 +827,11 @@ public abstract class AbstractStateMachine<S, E> extends StateMachineObjectSuppo
 	}
 
 	synchronized void setCurrentState(State<S, E> state, Message<E> message, Transition<S, E> transition, boolean exit, StateMachine<S, E> stateMachine) {
+		setCurrentState(state, message, transition, exit, stateMachine, null, null);
+	}
+
+	synchronized void setCurrentState(State<S, E> state, Message<E> message, Transition<S, E> transition, boolean exit,
+			StateMachine<S, E> stateMachine, Collection<State<S, E>> sources, Collection<State<S, E>> targets) {
 
 		State<S, E> findDeep = findDeepParent(state);
 		boolean isTargetSubOf = false;
@@ -901,7 +912,7 @@ public abstract class AbstractStateMachine<S, E> extends StateMachineObjectSuppo
 				}
 				currentState = findDeep;
 				if (shouldTryEntry) {
-					entryToState(currentState, message, transition, stateMachine);
+					entryToState(currentState, message, transition, stateMachine, sources, targets);
 				}
 
 				if (currentState.isSubmachineState()) {
@@ -985,11 +996,16 @@ public abstract class AbstractStateMachine<S, E> extends StateMachineObjectSuppo
 	}
 
 	private void entryToState(State<S, E> state, Message<E> message, Transition<S, E> transition, StateMachine<S, E> stateMachine) {
+		entryToState(state, message, transition, stateMachine, null, null);
+	}
+
+	private void entryToState(State<S, E> state, Message<E> message, Transition<S, E> transition, StateMachine<S, E> stateMachine,
+			Collection<State<S, E>> sources, Collection<State<S, E>> targets) {
 		if (state == null) {
 			return;
 		}
 		log.trace("Trying Enter state=[" + state + "]");
-		StateContext<S, E> stateContext = buildStateContext(Stage.STATE_ENTRY, message, transition, stateMachine);
+		StateContext<S, E> stateContext = buildStateContext(Stage.STATE_ENTRY, message, transition, stateMachine, sources, targets);
 
 		if (transition != null) {
 			State<S, E> findDeep1 = findDeepParent(transition.getTarget());
@@ -1026,5 +1042,4 @@ public abstract class AbstractStateMachine<S, E> extends StateMachineObjectSuppo
 			return false;
 		}
 	}
-
 }

spring-statemachine-core/src/main/java/org/springframework/statemachine/support/DefaultStateContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,6 +15,8 @@
  */
 package org.springframework.statemachine.support;
 
+import java.util.Collection;
+
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageHeaders;
 import org.springframework.statemachine.ExtendedState;
@@ -41,6 +43,8 @@ public class DefaultStateContext<S, E> implements StateContext<S, E> {
 	private final StateMachine<S, E> stateMachine;
 	private final State<S, E> source;
 	private final State<S, E> target;
+	private final Collection<State<S, E>> sources;
+	private final Collection<State<S, E>> targets;
 	private final Exception exception;
 
 	/**
@@ -67,6 +71,39 @@ public class DefaultStateContext<S, E> implements StateContext<S, E> {
 		this.source = source;
 		this.target = target;
 		this.exception = exception;
+		this.sources = null;
+		this.targets = null;
+	}
+
+	/**
+	 * Instantiates a new default state context.
+	 *
+	 * @param stage the stage
+	 * @param message the message
+	 * @param messageHeaders the message headers
+	 * @param extendedState the extended state
+	 * @param transition the transition
+	 * @param stateMachine the state machine
+	 * @param source the source
+	 * @param target the target
+	 * @param sources the sources
+	 * @param targets the targets
+	 * @param exception the exception
+	 */
+	public DefaultStateContext(Stage stage, Message<E> message, MessageHeaders messageHeaders, ExtendedState extendedState,
+			Transition<S, E> transition, StateMachine<S, E> stateMachine, State<S, E> source, State<S, E> target,
+			Collection<State<S, E>> sources, Collection<State<S, E>> targets, Exception exception) {
+		this.stage = stage;
+		this.message = message;
+		this.messageHeaders = messageHeaders;
+		this.extendedState = extendedState;
+		this.transition = transition;
+		this.stateMachine = stateMachine;
+		this.source = source;
+		this.target = target;
+		this.sources = sources;
+		this.targets = targets;
+		this.exception = exception;
 	}
 
 	@Override
@@ -119,11 +156,21 @@ public class DefaultStateContext<S, E> implements StateContext<S, E> {
 		return source != null ? source : (transition != null ? transition.getSource() : null);
 	}
 
+	@Override
+	public Collection<State<S, E>> getSources() {
+		return sources;
+	}
+
 	@Override
 	public State<S, E> getTarget() {
 		return target != null ? target : (transition != null ? transition.getTarget() : null);
 	}
 
+	@Override
+	public Collection<State<S, E>> getTargets() {
+		return targets;
+	}
+
 	@Override
 	public Exception getException() {
 		return exception;
@@ -133,7 +180,6 @@ public class DefaultStateContext<S, E> implements StateContext<S, E> {
 	public String toString() {
 		return "DefaultStateContext [stage=" + stage + ", message=" + message + ", messageHeaders=" + messageHeaders + ", extendedState="
 				+ extendedState + ", transition=" + transition + ", stateMachine=" + stateMachine + ", source=" + source + ", target="
-				+ target + ", exception=" + exception + "]";
+				+ target + ", sources=" + sources + ", targets=" + targets + ", exception=" + exception + "]";
 	}
-
 }