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.services.metrics;
  
  import java.util.Collections;
  import java.util.Set;
  
  import org.apache.causeway.applib.annotation.DomainObject;
  import org.apache.causeway.applib.services.bookmark.Bookmark;
  import org.apache.causeway.applib.services.iactn.InteractionProvider;
  import org.apache.causeway.schema.ixn.v2.MemberExecutionDto;
  
  /**
   * Hooks into the transaction nechanism to provide a counters relating to
   * numbers of object loaded, dirtied etc.
   *
   * <p>
   *     Only entities with {@link DomainObject#entityChangePublishing()} enabled (in other words, auditing)
   *     are counted.
   * </p>
   *
   * @implNote Implementation depends upon ORM callbacks.
   * @since 1.x {@index}
   */
  public interface MetricsService {
  
      /**
       * The number of entities that were loaded (but not necessarily modified) from the database.
       *
       * <p>
       * Is captured within {@link MemberExecutionDto#getMetrics()} (accessible from {@link InteractionProvider#currentInteraction()}).
       *
       * @see #entitiesLoaded()
       * @see #numberEntitiesDirtied()
       */
      int numberEntitiesLoaded();
  
      /**
       * Returns the bookmarks of the entities loaded within the transaction.
       *
       * <p>
       * Requires detailed metrics to be enabled using config param.
       *
       * @see #numberEntitiesLoaded()
       * @see #entitiesDirtied()
       */
      default Set<Bookmark> entitiesLoaded() {
          return Collections.emptySet();
      }
  
      /**
       * The number of entities that were modified within the transaction.
       *
       * <p>
       * Is captured within {@link MemberExecutionDto#getMetrics()} (accessible from {@link InteractionProvider#currentInteraction()}.
       *
       * @see #numberEntitiesLoaded()
       * @see #entitiesDirtied()
       */
      int numberEntitiesDirtied();
  
      /**
       * Returns the bookmarks of the entities that were modified within the transaction.
       *
       * <p>
       * Requires detailed metrics to be enabled using config param.
       *
       * @see #numberEntitiesDirtied()
       * @see #entitiesLoaded()
       */
      default Set<Bookmark> entitiesDirtied() {
          return Collections.emptySet();
      }
  }
  
  