org.glassfish.pfl.basic.fsm

Interface Action

All Known Implementing Classes:

Action.Base

public interface Action

An Action may be associated with a transition between to states. The transition action doIt method is called before the transition takes place.

Author:

Ken Cavanaugh

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	Action.Base

Method Summary

Modifier and Type	Method and Description
void	doIt(FSM fsm, Input in) Called by the state engine to perform an action before a state transition takes place.

Method Detail

doIt

void doIt(FSM fsm,
          Input in)

Called by the state engine to perform an action before a state transition takes place. The FSM is passed so that the Action may examine the state of the FSM. Note that an action should complete in a timely manner. If the state machine is used for concurrency control with multiple threads, the action must not allow multiple threads to run simultaneously in the state machine, as the state could be corrupted. Any exception thrown by the Action for the transition will be propagated to doIt.

Parameters:

fsm - is the state machine causing this action.

in - is the input that caused the transition.