akka.japi.pf.FSMStopBuilder Maven / Gradle / Ivy

/*
 * Copyright (C) 2009-2020 Lightbend Inc. 
 */

package akka.japi.pf;

import akka.actor.FSM;
import scala.PartialFunction;
import scala.runtime.BoxedUnit;

/**
 * Builder used to create a partial function for {@link akka.actor.FSM#onTermination}.
 *
 * @param  the state type
 * @param  the data type
 */
public class FSMStopBuilder {

  private UnitPFBuilder> builder = new UnitPFBuilder>();

  /**
   * Add a case statement that matches on an {@link FSM.Reason}.
   *
   * @param reason the reason for the termination
   * @param apply an action to apply to the event and state data if there is a match
   * @return the builder with the case statement added
   */
  public FSMStopBuilder stop(final FSM.Reason reason, final FI.UnitApply2 apply) {
    builder.match(
        FSM.StopEvent.class,
        new FI.TypedPredicate() {
          @Override
          public boolean defined(FSM.StopEvent e) {
            return reason.equals(e.reason());
          }
        },
        new FI.UnitApply() {
          public void apply(FSM.StopEvent e) throws Exception {
            @SuppressWarnings("unchecked")
            S s = (S) e.currentState();
            @SuppressWarnings("unchecked")
            D d = (D) e.stateData();
            apply.apply(s, d);
          }
        });

    return this;
  }

  /**
   * Add a case statement that matches on a reason type.
   *
   * @param reasonType the reason type to match on
   * @param apply an action to apply to the reason, event and state data if there is a match
   * @param  the reason type to match on
   * @return the builder with the case statement added
   */
  public 
 FSMStopBuilder stop(
      final Class
 reasonType, final FI.UnitApply3 apply) {
    return this.stop(
        reasonType,
        new FI.TypedPredicate
() {
          @Override
          public boolean defined(P p) {
            return true;
          }
        },
        apply);
  }

  /**
   * Add a case statement that matches on a reason type and a predicate.
   *
   * @param reasonType the reason type to match on
   * @param apply an action to apply to the reason, event and state data if there is a match
   * @param predicate a predicate that will be evaluated on the reason if the type matches
   * @param 
 the reason type to match on
   * @return the builder with the case statement added
   */
  public 
 FSMStopBuilder stop(
      final Class
 reasonType,
      final FI.TypedPredicate predicate,
      final FI.UnitApply3 apply) {
    builder.match(
        FSM.StopEvent.class,
        new FI.TypedPredicate() {
          @Override
          public boolean defined(FSM.StopEvent e) {
            if (reasonType.isInstance(e.reason())) {
              @SuppressWarnings("unchecked")
              P p = (P) e.reason();
              return predicate.defined(p);
            } else {
              return false;
            }
          }
        },
        new FI.UnitApply() {
          public void apply(FSM.StopEvent e) throws Exception {
            @SuppressWarnings("unchecked")
            P p = (P) e.reason();
            @SuppressWarnings("unchecked")
            S s = (S) e.currentState();
            @SuppressWarnings("unchecked")
            D d = (D) e.stateData();
            apply.apply(p, s, 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, BoxedUnit> build() {
    return builder.build();
  }
}