Package 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, Context) 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:

  • Constructor Details

    • Decision

      public Decision(int workflowId, Map<String,Serializable> workflowContext, String messageKey, Principal actor, Outcome defaultOutcome)
      Constructs a new Decision for a required "actor" Principal, having a default Outcome.
      Parameters:
      workflowId - the parent workflow id to set
      workflowContext - the parent workflow context to set
      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 Details

    • 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, Context context) 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
      context - wiki context of the Decision
      Throws:
      WikiException - if the act of restarting the Workflow throws an exception

    • execute

      public Outcome execute(Context context) 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, Context) 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
      Parameters:
      context - executing wiki context.
      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