org.arch4j.clientcontroller
Class State

java.lang.Object
  |
  +--org.arch4j.clientcontroller.State

Direct Known Subclasses:

ErrorState

public abstract class State

extends Object

This abstract class defines basic behavior for a state.

All deriving state implementations should have a section of javadoc in the class heading based on the following:

State overview

• State name
• MyState
• Context values read by entry
• MyReadOnlyValues
• Context values added on entry
• MyAddedValues
• Context values updated on entry
• MyAddedValues
• Context values removed on entry
• MyRemovedValues
• Context values expected on exit
• MyExpectedValues
• Context values added on exit
• MyAddedValues
• Context values updated on exit
• MyAddedValues
• Context values removed on exit
• MyRemovedValues
• Transitions by priority
1. MyOrderedTransitions
• EmbeddedStateMachine entry transition
• MyEmbeddedStateMachineEntryTransition

Version:

1.0

Author:

David Colwell

Constructor Summary

State()
Constructs a State object.

Method Summary

protected void	appendTransition(Transition aTransition) Allows subclasses to specify Transitions.
abstract void	buildTransitionList() Build the transitionList of Transitions available from this State.
protected void	createEmbeddedStateMachine(Transition entryTransition, StateContext context) Helper method to create an embedded StateMachine.
protected void	createEmbeddedStateMachine(Transition entryTransition, Transition exitTransition, StateContext context) Helper method to create an embedded StateMachine.
void	entryAction(StateContext context) Perform the entry action for this state.
void	exitAction(StateContext context) Perform the exit action for this state.
protected StateMachine	getEmbeddedStateMachine() Retrieves the embedded state machine.
abstract String	getStateName() Retrieves the unique state name.
protected List	getTransitionList() Retrieve the list of Transitions available from this State.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

State

public State()

Constructs a State object. Subclass constructors will call this default constructor implicitly.

Method Detail

appendTransition

protected void appendTransition(Transition aTransition)

Allows subclasses to specify Transitions. Note that the order the Transitions are added implies priority. If two Transitions are not mutually exclusive in their events and guard conditions, then the first in the list will execute and the second will not.

See Also:

buildTransitionList()

createEmbeddedStateMachine

protected void createEmbeddedStateMachine(Transition entryTransition,
                                          StateContext context)
                                   throws StateMachineException

Helper method to create an embedded StateMachine.

Throws:

StateMachineException - if there is any problem processing the request. This might include a missing key-value, application server problems, failed domain validation, or data access errors.

createEmbeddedStateMachine

protected void createEmbeddedStateMachine(Transition entryTransition,
                                          Transition exitTransition,
                                          StateContext context)
                                   throws StateMachineException

Helper method to create an embedded StateMachine.

Throws:

StateMachineException - if there is any problem processing the request. This might include a missing key-value, application server problems, failed domain validation, or data access errors.

getEmbeddedStateMachine

protected StateMachine getEmbeddedStateMachine()

Retrieves the embedded state machine.

Returns:

The embedded state machine, if it exists, otherwise null.

getTransitionList

protected final List getTransitionList()

Retrieve the list of Transitions available from this State.

getStateName

public abstract String getStateName()

Retrieves the unique state name. Note that this should not be defined to contain the '~' character as this is used as the full state name seperator.

entryAction

public void entryAction(StateContext context)
                 throws StateMachineException

Perform the entry action for this state. This will typically be data retrieval and setup. If this state has an embedded state machine, a call to createEmbeddedStateMachine should go here as well.

Throws:

StateMachineException - if there is a system related problem processing the request. This might be a missing key-value, application server problems, failed domain validation, or data access errors.

exitAction

public void exitAction(StateContext context)
                throws StateMachineException

Perform the exit action for this state. This will typically be for clean-up, if necessary.

Throws:

StateMachineException - if there is a system related problem processing the request. This might be a missing key-value, application server problems, failed domain validation, or data access errors.

buildTransitionList

public abstract void buildTransitionList()

Build the transitionList of Transitions available from this State. The implementation method will use addTransition to add new Transitions.