1   /* Copyright 2022-2025 Romain Serra
2    * Licensed to CS GROUP (CS) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * CS licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *   http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.orekit.attitudes;
18  
19  import org.orekit.propagation.SpacecraftState;
20  
21  /** Interface for attitude switch notifications.
22   * <p>
23   * This interface is intended to be implemented by users who want to be
24   * notified when an attitude switch occurs.
25   * </p>
26   * @since 13.0
27   * @see AbstractSwitchingAttitudeProvider
28   */
29  @FunctionalInterface
30  public interface AttitudeSwitchHandler {
31  
32      /** Method called when attitude is switched from one law to another law.
33       * @param preceding attitude law used preceding the switch (i.e. in the past
34       * of the switch event for a forward propagation, or in the future
35       * of the switch event for a backward propagation)
36       * @param following attitude law used following the switch (i.e. in the future
37       * of the switch event for a forward propagation, or in the past
38       * of the switch event for a backward propagation)
39       * @param state state at switch time (with attitude computed using the past law)
40       */
41      void switchOccurred(AttitudeProvider preceding, AttitudeProvider following, SpacecraftState state);
42  }