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.clock;
  
  import jakarta.inject.Inject;
  import jakarta.inject.Named;
  import jakarta.inject.Provider;
  
  import org.springframework.beans.factory.annotation.Qualifier;
  import org.springframework.stereotype.Service;
  
  import org.apache.causeway.applib.CausewayModuleApplib;
  import org.apache.causeway.applib.annotation.PriorityPrecedence;
  import org.apache.causeway.applib.clock.VirtualClock;
  import org.apache.causeway.applib.services.iactnlayer.InteractionContext;
  import org.apache.causeway.applib.services.iactnlayer.InteractionLayerTracker;
  
  import lombok.RequiredArgsConstructor;
  
  /**
   * This service allows an application to be decoupled from the system time.
   * The most common use case is in support of testing scenarios, to &quot;mock the clock&quot;.
   * Use of this service also opens up the use of centralized
   * co-ordinated time management through a centralized time service.
   *
   * @since 1.x revised for 2.0 {@index}
   */
  @Service
  @Named(ClockService.LOGICAL_TYPE_NAME)
  @jakarta.annotation.Priority(PriorityPrecedence.MIDPOINT)
  @Qualifier("Default")
  @RequiredArgsConstructor(onConstructor_ = {@Inject})
  public class ClockService {
  
      static final String LOGICAL_TYPE_NAME = CausewayModuleApplib.NAMESPACE + ".ClockService";
  
      private final Provider<InteractionLayerTracker> interactionLayerTrackerProvider;
  
      public VirtualClock getClock() {
          return interactionLayerTrackerProvider.get().currentInteractionContext()
                  .map(InteractionContext::getClock)
                  .orElseGet(VirtualClock::system);
      }
  
      // -- SHORTCUTS
  
      public long getEpochMillis() {
          return getClock().nowAsEpochMilli();
      }
  
  }
  