pekko/akka-actor/src/main/java/akka/japi/pf/FSMStateFunctionBuilder.java
2014-01-24 11:47:57 +01:00

133 lines
4.2 KiB
Java

/**
* Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
*/
package akka.japi.pf;
import akka.actor.FSM;
import scala.PartialFunction;
import java.util.List;
/**
* Builder used to create a partial function for {@link akka.actor.FSM#whenUnhandled}.
*
* @param <S> the state type
* @param <D> the data type
*/
@SuppressWarnings("rawtypes")
public class FSMStateFunctionBuilder<S, D> {
private PFBuilder<FSM.Event<D>, FSM.State<S, D>> builder =
new PFBuilder<FSM.Event<D>, FSM.State<S, D>>();
/**
* Add a case statement that matches on an event and data type.
*
* @param eventType the event type to match on
* @param dataType the data type to match on
* @param apply an action to apply to the event and state data if there is a match
* @param <P> the event type to match on
* @param <Q> the data type to match on
* @return the builder with the case statement added
*/
public <P, Q> FSMStateFunctionBuilder<S, D> event(final Class<P> eventType,
final Class<Q> dataType,
final FI.Apply2<P, Q, FSM.State<S, D>> apply) {
builder.match(FSM.Event.class,
new FI.TypedPredicate<FSM.Event>() {
@Override
public boolean defined(FSM.Event e) {
return eventType.isInstance(e.event()) && dataType.isInstance(e.stateData());
}
},
new FI.Apply<FSM.Event, FSM.State<S, D>>() {
public FSM.State<S, D> apply(FSM.Event e) {
@SuppressWarnings("unchecked")
P p = (P) e.event();
@SuppressWarnings("unchecked")
Q q = (Q) e.stateData();
return apply.apply(p, q);
}
}
);
return this;
}
/**
* Add a case statement that matches on the data type and if any of the event types
* in the list match or any of the event instances in the list compares equal.
*
* @param eventMatches a list of types or instances to match against
* @param dataType the data type to match on
* @param apply an action to apply to the event and state data if there is a match
* @param <Q> the data type to match on
* @return the builder with the case statement added
*/
public <Q> FSMStateFunctionBuilder<S, D> event(final List<Object> eventMatches,
final Class<Q> dataType,
final FI.Apply<Q, FSM.State<S, D>> apply) {
builder.match(FSM.Event.class,
new FI.TypedPredicate<FSM.Event>() {
@Override
public boolean defined(FSM.Event e) {
if (!dataType.isInstance(e.stateData()))
return false;
boolean emMatch = false;
Object event = e.event();
for (Object em : eventMatches) {
if (em instanceof Class) {
Class emc = (Class) em;
emMatch = emc.isInstance(event);
} else {
emMatch = event.equals(em);
}
if (emMatch)
break;
}
return emMatch;
}
},
new FI.Apply<FSM.Event, FSM.State<S, D>>() {
public FSM.State<S, D> apply(FSM.Event e) {
@SuppressWarnings("unchecked")
Q q = (Q) e.stateData();
return apply.apply(q);
}
}
);
return this;
}
/**
* Add a case statement that matches on any type of event.
*
* @param apply an action to apply to the event and state data
* @return the builder with the case statement added
*/
public FSMStateFunctionBuilder<S, D> anyEvent(final FI.Apply2<Object, D, FSM.State<S, D>> apply) {
builder.match(FSM.Event.class,
new FI.Apply<FSM.Event, FSM.State<S, D>>() {
public FSM.State<S, D> apply(FSM.Event e) {
@SuppressWarnings("unchecked")
D d = (D) e.stateData();
return apply.apply(e.event(), d);
}
});
return this;
}
/**
* Build a {@link scala.PartialFunction} from this builder.
* After this call the builder will be reset.
*
* @return a PartialFunction for this builder.
*/
public PartialFunction<FSM.Event<D>, FSM.State<S, D>> build() {
return builder.build();
}
}