akka.japi.pf.FSMTransitionHandlerBuilder Maven / Gradle / Ivy
/*
* Copyright (C) 2009-2020 Lightbend Inc.
*/
package akka.japi.pf;
import scala.PartialFunction;
import scala.runtime.BoxedUnit;
import scala.Tuple2;
/**
* Builder used to create a partial function for {@link akka.actor.FSM#onTransition}.
*
* @param the state type
*/
public class FSMTransitionHandlerBuilder {
private final UnitPFBuilder> builder = new UnitPFBuilder>();
/**
* Add a case statement that matches on a from state and a to state.
*
* @param fromState the from state to match on, or null for any
* @param toState the to state to match on, or null for any
* @param apply an action to apply when the states match
* @return the builder with the case statement added
*/
public FSMTransitionHandlerBuilder state(
final S fromState, final S toState, final FI.UnitApplyVoid apply) {
builder.match(
Tuple2.class,
new FI.TypedPredicate() {
@Override
public boolean defined(Tuple2 t) {
return (fromState == null || fromState.equals(t._1()))
&& (toState == null || toState.equals(t._2()));
}
},
new FI.UnitApply() {
@Override
public void apply(Tuple2 t) throws Exception {
apply.apply();
}
});
return this;
}
/**
* Add a case statement that matches on a from state and a to state.
*
* @param fromState the from state to match on, or null for any
* @param toState the to state to match on, or null for any
* @param apply an action to apply when the states match
* @return the builder with the case statement added
*/
public FSMTransitionHandlerBuilder state(
final S fromState, final S toState, final FI.UnitApply2 apply) {
builder.match(
Tuple2.class,
new FI.TypedPredicate() {
@Override
public boolean defined(Tuple2 t) {
return (fromState == null || fromState.equals(t._1()))
&& (toState == null || toState.equals(t._2()));
}
},
new FI.UnitApply() {
@Override
public void apply(Tuple2 t) throws Exception {
@SuppressWarnings("unchecked")
S sf = (S) t._1();
@SuppressWarnings("unchecked")
S st = (S) t._2();
apply.apply(sf, st);
}
});
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, BoxedUnit> build() {
return builder.build();
}
}