content: /*
   *  Licensed to the Apache Software Foundation (ASF) under one
   *  or more contributor license agreements.  See the NOTICE file
   *  distributed with this work for additional information
   *  regarding copyright ownership.  The ASF licenses this file
   *  to you under the Apache License, Version 2.0 (the
   *  "License"); you may not use this file except in compliance
   *  with the License.  You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License.
   */
  package org.apache.causeway.applib.events.domain;
  
  import java.util.List;
  
  import org.apache.causeway.applib.annotation.Action;
  import org.apache.causeway.applib.annotation.SemanticsOf;
  import org.apache.causeway.applib.util.ObjectContracts;
  import org.apache.causeway.applib.util.ToString;
  
  import lombok.Getter;
  import lombok.Setter;
  
  /**
   * Fired whenever the framework interacts with a domain object's action.
   *
   * <p>
   * This is the specialization of {@link AbstractDomainEvent}, for actions,
   * which should then be further subclassed by domain application.
   * </p>
   *
   * <p>
   * The class has a number of responsibilities (in addition to those it
   * inherits):
   * </p>
   *
   * <ul>
   *     <li>
   *          capture the arguments for each of the action's parameters
   *     </li>
   *     <li>
   *          provide selected metadata about the action parameters from the
   *          metamodel (names, types)
   *     </li>
   * </ul>
   *
   * <p>
   * The class itself is instantiated automatically by the framework using a
   * no-arg constructor; fields are set reflectively.
   * </p>
   *
   * @since 1.x {@index}
   */
  public abstract class ActionDomainEvent<S> extends AbstractDomainEvent<S> {
  
      /**
       * This class is the default for the
       * {@link org.apache.causeway.applib.annotation.Action#domainEvent()} annotation attribute.
       *
       * <p>
       * Whether this raises an event or not depends upon the
       * <tt>causeway.applib.annotation.action.domain-event.post-for-default</tt>
       * configuration property.
       * </p>
       */
      public static class Default extends ActionDomainEvent<Object> {}
  
      /**
       * Convenience class to use indicating that an event should <i>not</i> be
       * posted (irrespective of the configuration property setting for the
       * {@link Default} event.
       */
      public static class Noop extends ActionDomainEvent<Object> {}
  
      /**
       * Convenience class meaning that an event <i>should</i> be posted
       * (irrespective of the configuration property setting for the
       * {@link Default} event..
       */
      public static class Doop extends ActionDomainEvent<Object> {}
  
      /**
       * Subtypes can define a no-arg constructor; the framework sets state
       * via (non-API) setters.
       */
      public ActionDomainEvent() {
      }
  
      /**
       * Subtypes can define a one-arg constructor; the framework sets state
       * via (non-API) setters.
       * <p>
       * A one-arg constructor is particularly useful in the context of non-static
       * DomainEvent class nesting.
       * @apiNote The Java compiler implicitly adds a constructor
       * to the non-static nested class, receiving the parent type as single argument.
       */
      public ActionDomainEvent(final S source) {
          super(source);
      }
  
      /**
       * The semantics of the action being invoked.
       *
       * <p>
       *     Copied over from {@link Action#semantics()}
       * </p>
       */
      @Getter
      private SemanticsOf semantics;
  
      /**
       * The names of the parameters of the actions.
       *
       * @see #getParameterTypes()
       * @see #getArguments()
       */
      @Getter
      private List<String> parameterNames;
  
      /**
       * The types of the parameters of the actions.
       *
       * <p>
       *     The {@link #getArguments() arguments} will be castable to the
       *     parameter types here.
       * </p>
       *
       * @see #getParameterNames()
       * @see #getArguments()
       */
      @Getter
      private List<Class<?>> parameterTypes;
  
      /**
       * The arguments being used to invoke the action.
       *
       * <p>
       * Populated at {@link AbstractDomainEvent.Phase#VALIDATE} and subsequent
       * phases (but null for {@link AbstractDomainEvent.Phase#HIDE hidden} and
       * {@link AbstractDomainEvent.Phase#DISABLE disable} phases).
       * </p>
       *
       * <p>
       *     The argument values can also be modified by event handlers
       *     during the {@link AbstractDomainEvent.Phase#EXECUTING} phase. The
       *     new value must be the same type as the expected value; the framework
       *     performs no sanity checks.
       * </p>
       *
       * @see #getParameterNames()
       * @see #getParameterTypes()
       */
      @Getter @Setter
      private List<Object> arguments;
  
      /**
       * The value returned by the action.
       *
       * <p>
       * Only available for the {@link AbstractDomainEvent.Phase#EXECUTED}
       * {@link #getEventPhase() phase}.
       * </p>
       */
      @Getter
      private Object returnValue;
  
      /**
       * Set by the framework.
       *
       * <p>
       * Event subscribers can replace the value with some other value if they
       * wish, though only in the {@link AbstractDomainEvent.Phase#EXECUTED} phase.
       * </p>
       */
      public void setReturnValue(final Object returnValue) {
          this.returnValue = returnValue;
      }
  
      /**
       * @apiNote : NOT API, set by the framework
       */
      public void setSemantics(final SemanticsOf semantics) {
          this.semantics = semantics;
      }
      /**
       * @apiNote : NOT API, set by the framework
       */
      public void setParameterNames(final List<String> parameterNames) {
          this.parameterNames = parameterNames;
      }
      /**
       * @apiNote : NOT API, set by the framework
       */
      public void setParameterTypes(final List<Class<?>> parameterTypes) {
          this.parameterTypes = parameterTypes;
      }
  
      private static final ToString<ActionDomainEvent<?>> toString = ObjectContracts.<ActionDomainEvent<?>>
      toString("source", ActionDomainEvent::getSource)
      .thenToString("identifier", ActionDomainEvent::getIdentifier)
      .thenToString("eventPhase", ActionDomainEvent::getEventPhase)
      ;
  
      @Override
      public String toString() {
          return toString.toString(this);
      }
  
  }
  