/**
* Returns the lowest shared parent of the other state or null if these states have no common
* parent.
*/
public State getLeastCommonParent(State other) {
State least = null;
State[] otherHierarchy = other.getHierarchy();
for (int i = 0; i < hierarchy.length; i++) {
if (otherHierarchy.length <= i) break;
else if (hierarchy[i] == other.getHierarchy()[i]) least = hierarchy[i];
else break;
}
return least;
}
/**
* Creates a new state.
*
* @param name A name that is unique within any state machine that contains this state
* @param type A state type as defined by {@link StateType}
* @param parent A parent state that contains this state if any
* @param entryAction An action to perform on entering the state
* @param exitAction An action to perform on leaving the state
*/
public State(String name, StateType type, State parent, Action entryAction, Action exitAction) {
this.name = name;
this.type = type;
this.parent = parent;
this.entryAction = entryAction;
this.exitAction = exitAction;
// Compute name and enclosing state hierarchy.
if (parent == null) {
this.qualifiedName = name;
this.hierarchy = new State[] {this};
} else {
this.qualifiedName = parent.getName() + ":" + name;
State[] parentArray = parent.getHierarchy();
State[] selfArray = new State[parentArray.length + 1];
for (int i = 0; i < parentArray.length; i++) selfArray[i] = parentArray[i];
selfArray[selfArray.length - 1] = this;
this.hierarchy = selfArray;
}
if (parent == null) {}
}
/** Returns true if the other state encloses this one. */
public boolean isSubstateOf(State other) {
if (parent == null) return false;
else if (parent == other) return true;
else return parent.isSubstateOf(other);
}