org.apache.wiki.workflow

Class Decision

java.lang.Object

org.apache.wiki.workflow.AbstractStep

org.apache.wiki.workflow.Decision

All Implemented Interfaces:

Serializable, Step

Direct Known Subclasses:

SimpleDecision, SimpleNotification

public abstract class Decision
extends AbstractStep

AbstractStep subclass that asks an actor Principal to choose an Outcome on behalf of an owner (also a Principal). The actor "makes the decision" by calling the decide(Outcome) method. When this method is called, it will set the Decision's Outcome to the one supplied. If the parent Workflow is in the Workflow.WAITING state, it will be re-started. Any checked WikiExceptions thrown by the workflow after re-start will be re-thrown to callers.

When a Decision completes, its AbstractStep.isCompleted() method returns true. It also tells its parent WorkflowManager to remove it from the list of pending tasks by calling DecisionQueue.remove(Decision).

To enable actors to choose an appropriate Outcome, Decisions can store arbitrary key-value pairs called "facts." These facts can be presented by the user interface to show details the actor needs to know about. Facts are added by calling classes to the Decision, in order of expected presentation, by the addFact(Fact) method. They can be retrieved, in order, via getFacts().

Since:

2.5

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Decision(Workflow workflow, String messageKey, Principal actor, Outcome defaultOutcome) Constructs a new Decision for a required "actor" Principal, having a default Outcome.

Method Summary

Modifier and Type	Method and Description
void	addFact(Fact fact) Appends a Fact to the list of Facts associated with this Decision.
void	decide(Outcome outcome) Sets this Decision's outcome, and restarts the parent Workflow if it is in the Workflow.WAITING state and this Decision is its currently active Step.
Outcome	execute() Default implementation that always returns Outcome.STEP_CONTINUE if the current Outcome isn't a completion (which will be true if the decide(Outcome) method hasn't been executed yet.
Principal	getActor() The Principal responsible for completing this Step, such as a system user or actor assigned to a Decision.
Outcome	getDefaultOutcome() Returns the default or suggested outcome, which must be one of those returned by AbstractStep.getAvailableOutcomes().
List<Fact>	getFacts() Returns the Facts associated with this Decision, in the order in which they were added.
int	getId() Returns the unique identifier for this Decision.
boolean	isReassignable() Returns true if the Decision can be reassigned to another actor.
void	reassign(Principal actor) Reassigns the Decision to a new actor (that is, provide an outcome).
void	setId(int id) Sets the unique identfier for this Decision.

Methods inherited from class org.apache.wiki.workflow.AbstractStep

addError, addSuccessor, getAvailableOutcomes, getEndTime, getErrors, getMessageArguments, getMessageKey, getOutcome, getOwner, getStartTime, getSuccessor, getWorkflow, isCompleted, isStarted, setOutcome, setWorkflow, start

Methods inherited from class java.lang.Object

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

Constructor Detail

Decision

public Decision(Workflow workflow,
                String messageKey,
                Principal actor,
                Outcome defaultOutcome)

Constructs a new Decision for a required "actor" Principal, having a default Outcome.

Parameters:

workflow - the parent Workflow object

messageKey - the i18n message key that represents the message the actor will see

actor - the Principal (e.g., a WikiPrincipal, Role, GroupPrincipal) who is required to select an appropriate Outcome

defaultOutcome - the Outcome that the user interface will recommend as the default choice

Method Detail

addFact

public final void addFact(Fact fact)

Appends a Fact to the list of Facts associated with this Decision.

Parameters:

fact - the new fact to add

decide

public void decide(Outcome outcome)
            throws WikiException

Sets this Decision's outcome, and restarts the parent Workflow if it is in the Workflow.WAITING state and this Decision is its currently active Step. Any checked WikiExceptions thrown by the workflow after re-start will be re-thrown to callers.

This method cannot be invoked if the Decision is not the current Workflow step; all other invocations will throw an IllegalStateException. If the Outcome supplied to this method is one one of the Outcomes returned by AbstractStep.getAvailableOutcomes(), an IllegalArgumentException will be thrown.

Parameters:

outcome - the Outcome of the Decision

Throws:

WikiException - if the act of restarting the Workflow throws an exception

execute

public Outcome execute()
                throws WikiException

Default implementation that always returns Outcome.STEP_CONTINUE if the current Outcome isn't a completion (which will be true if the decide(Outcome) method hasn't been executed yet. This method will also add the Decision to the associated DecisionQueue.

Specified by:

execute in interface Step

Specified by:

execute in class AbstractStep

Returns:

the Outcome of the execution

Throws:

WikiException - never

getActor

public final Principal getActor()

The Principal responsible for completing this Step, such as a system user or actor assigned to a Decision.

Specified by:

getActor in interface Step

Specified by:

getActor in class AbstractStep

Returns:

the responsible Principal

getDefaultOutcome

public Outcome getDefaultOutcome()

Returns the default or suggested outcome, which must be one of those returned by AbstractStep.getAvailableOutcomes(). This method is guaranteed to return a non-null Outcome.

Returns:

the default outcome.

getFacts

public final List<Fact> getFacts()

Returns the Facts associated with this Decision, in the order in which they were added.

Returns:

the list of Facts

getId

public final int getId()

Returns the unique identifier for this Decision. Normally, this ID is programmatically assigned when the Decision is added to the DecisionQueue.

Returns:

the identifier

isReassignable

public boolean isReassignable()

Returns true if the Decision can be reassigned to another actor. This implementation always returns true.

Returns:

the result

reassign

public final void reassign(Principal actor)

Reassigns the Decision to a new actor (that is, provide an outcome). If the Decision is not reassignable, this method throws an IllegalArgumentException.

Parameters:

actor - the actor to reassign the Decision to

setId

public final void setId(int id)

Sets the unique identfier for this Decision.

Parameters:

id - the identifier