edu.luc.cs.trull
Class If

java.lang.Object
  edu.luc.cs.trull.EmptyComponent
      edu.luc.cs.trull.TerminatingComponent
          edu.luc.cs.trull.AbstractComponent
              edu.luc.cs.trull.AbstractCombinator
                  edu.luc.cs.trull.Switch
                      edu.luc.cs.trull.If

All Implemented Interfaces:

Combinator, Component, PropertyChangeSource, Startable, Suspendable, Terminating, java.beans.PropertyChangeListener, java.util.EventListener

public class If
extends Switch

A data-driven selection mechanism that evaluates its predicate and immediately chooses and starts the corresponding branch. The resulting component terminates when the chosen branch terminates.

Nested Class Summary

Nested classes/interfaces inherited from class edu.luc.cs.trull.Switch

Switch.LocalListener, Switch.SwitchTerminationListener

Nested classes/interfaces inherited from class edu.luc.cs.trull.AbstractCombinator

AbstractCombinator.DefaultTerminationListener

Field Summary

private EventPredicate

predicate The predicate used by this combinator.

Fields inherited from class edu.luc.cs.trull.AbstractCombinator

components

Constructor Summary

If()
Constructs an empty If component.

If(EventPredicate predicate, Component yes)
Constructs an If component with only a yes branch.

If(EventPredicate predicate, Component yes, Component no)
Constructs an If component.

Method Summary

EventPredicate	getPredicate() Returns the event predicate used by this If component.
protected static EventValuator	predicateToValuator(EventPredicate predicate) Converts an event predicate to an event valuator.
void	setPredicate(EventPredicate predicate) Sets the event predicate used by this If component.

Methods inherited from class edu.luc.cs.trull.Switch

disconnectComponent, getChildTerminationListener, getCurrentComponent, getValuator, propertyChange, removeComponent, resume, setValuator, start, stop, suspend, switchToComponent

Methods inherited from class edu.luc.cs.trull.AbstractCombinator

addComponent, addComponent, addComponent, getComponent, getComponentCount, getComponents, removeAllComponents, removeComponent

Methods inherited from class edu.luc.cs.trull.AbstractComponent

addPropertyChangeListener, firePropertyChange, firePropertyChange, firePropertyChange, getExternalListeners, getPropertyChangeListeners, removePropertyChangeListener

Methods inherited from class edu.luc.cs.trull.TerminatingComponent

fireTermination, getParent, getTermEvent, scheduleTermination, setTerminationListener

Methods inherited from class edu.luc.cs.trull.EmptyComponent

getTerminationListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.luc.cs.trull.PropertyChangeSource

addPropertyChangeListener, getPropertyChangeListeners, removePropertyChangeListener

Methods inherited from interface edu.luc.cs.trull.Terminating

getTerminationListener, setTerminationListener

Field Detail

predicate

private EventPredicate predicate

The predicate used by this combinator.

Constructor Detail

If

public If()

Constructs an empty If component. Specific properties can be changed later.

If

public If(EventPredicate predicate,
          Component yes)

Constructs an If component with only a yes branch.

Parameters:

predicate - the event predicate used in choosing a branch.

yes - the branch chosen when the predicate evalutes to true.

If

public If(EventPredicate predicate,
          Component yes,
          Component no)

Constructs an If component.

Parameters:

predicate - the event predicate used in choosing a branch.

yes - the branch chosen when the predicate evalutes to true.

no - the branch chosen when the predicate evalutes to false.

Method Detail

getPredicate

public EventPredicate getPredicate()

Returns the event predicate used by this If component.

Returns:

the event predicate.

predicateToValuator

protected static EventValuator predicateToValuator(EventPredicate predicate)

Converts an event predicate to an event valuator. This method is used since the If combinator is implemented as a Switch.

Parameters:

predicate - the event predicate.

Returns:

the corresponding event valuator.

setPredicate

public void setPredicate(EventPredicate predicate)

Sets the event predicate used by this If component.

Parameters:

predicate - the event predicate.