Package org.apache.mina.statemachine.transition

Class AbstractTransition

java.lang.Object

org.apache.mina.statemachine.transition.AbstractTransition

All Implemented Interfaces:

Transition

Direct Known Subclasses:

MethodTransition, NoopTransition

public abstract class AbstractTransition
extends java.lang.Object
implements Transition

Abstract Transition implementation. Takes care of matching the current Event's id against the id of the Event this Transition handles. To handle any Event the id should be set to Event.WILDCARD_EVENT_ID.

Field Summary

Fields

Modifier and Type	Field	Description
private java.lang.Object	eventId	The accepted event ID
private State	nextState	The next state, if any

Constructor Summary

Constructors

Constructor	Description
AbstractTransition()	Creates a new instance with a reflexive State as next state and for the wild card Event id.
AbstractTransition(java.lang.Object eventId)	Creates a new instance which will loopback to the same State for the specified Event id.
AbstractTransition(java.lang.Object eventId, State nextState)	Creates a new instance with the specified State as next state and for the specified Event id.
AbstractTransition(State nextState)	Creates a new instance with the specified State as next state and for the wild card Event id.

Method Summary

Modifier and Type	Method	Description
protected abstract boolean	doExecute(Event event)	Executes this Transition.
boolean	equals(java.lang.Object o)
boolean	execute(Event event)	Executes this Transition.
State	getNextState()
int	hashCode()
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

eventId

private final java.lang.Object eventId

The accepted event ID

nextState

private final State nextState

The next state, if any

Constructor Detail

AbstractTransition

public AbstractTransition(java.lang.Object eventId)

Creates a new instance which will loopback to the same State for the specified Event id.

Parameters:

eventId - the Event id.

AbstractTransition

public AbstractTransition(java.lang.Object eventId,
                          State nextState)

Creates a new instance with the specified State as next state and for the specified Event id.

Parameters:

eventId - the Event id.

nextState - the next State.

AbstractTransition

public AbstractTransition(State nextState)

Creates a new instance with the specified State as next state and for the wild card Event id.

Parameters:

nextState - the next State.

AbstractTransition

public AbstractTransition()

Creates a new instance with a reflexive State as next state and for the wild card Event id.

Method Detail

getNextState

public State getNextState()

Specified by:

getNextState in interface Transition

Returns:

the State which the StateMachine should move to if this Transition is taken and Transition.execute(Event) returns true. null if this Transition is a loopback Transition.

execute

public boolean execute(Event event)

Executes this Transition. It is the responsibility of this Transition to determine whether it actually applies for the specified Event. If this Transition doesn't apply nothing should be executed and false must be returned. The method will accept any Event if it is registered with the wild card event ID ('*'), and the event ID it is declared for (ie, the event ID that has been passed as a parameter to this transition constructor.)

Specified by:

execute in interface Transition

Parameters:

event - the current Event.

Returns:

true if the Transition was executed, false otherwise.

doExecute

protected abstract boolean doExecute(Event event)

Executes this Transition. This method doesn't have to check if the Event's id matches because execute(Event) has already made sure that that is the case.

Parameters:

event - the current Event.

Returns:

true if the Transition has been executed successfully and the StateMachine should move to the next State. false otherwise.

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object