1   /* Copyright 2002-2025 CS GROUP
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.estimation.measurements.generation;
18  
19  import org.orekit.estimation.measurements.EstimatedMeasurementBase;
20  import org.orekit.estimation.measurements.ObservedMeasurement;
21  import org.orekit.time.AbsoluteDate;
22  import org.orekit.time.DatesSelector;
23  
24  import java.util.function.Predicate;
25  
26  /** {@link Scheduler} generating measurements sequences continuously.
27   * <p>
28   * Continuous schedulers continuously generate measurements following a repetitive pattern.
29   * The repetitive pattern can be either a continuous stream of measurements separated by
30   * a constant step (for example one measurement every 60s), or several sequences of measurements
31   * at high rate up to a maximum number, with a rest period between sequences (for example
32   * sequences of up to 256 measurements every 100ms with 300s between each sequence).
33   * </p>
34   * @param <T> the type of the measurement
35   * @author Luc Maisonobe
36   * @since 9.3
37   */
38  public class ContinuousScheduler<T extends ObservedMeasurement<T>> extends AbstractScheduler<T> {
39  
40      /** Simple constructor.
41       * <p>
42       * BEWARE! Dates selectors often store internally the last selected dates, so they are not
43       * reusable across several {@link EventBasedScheduler instances}. A separate selector
44       * should be used for each scheduler.
45       * </p>
46       * <p>
47       * This constructor calls {@link #ContinuousScheduler(MeasurementBuilder, DatesSelector, Predicate)}
48       * whith the predicate set to accept all generated measurements.
49       * </p>
50       * @param builder builder for individual measurements
51       * @param selector selector for dates (beware that selectors are generally not
52       * reusable across several {@link EventBasedScheduler instances}, each selector should
53       * be dedicated to one scheduler
54       */
55      public ContinuousScheduler(final MeasurementBuilder<T> builder, final DatesSelector selector) {
56          super(builder, selector, e -> true);
57      }
58  
59      /** Simple constructor.
60       * <p>
61       * BEWARE! Dates selectors often store internally the last selected dates, so they are not
62       * reusable across several {@link EventBasedScheduler instances}. A separate selector
63       * should be used for each scheduler.
64       * </p>
65       * @param builder builder for individual measurements
66       * @param selector selector for dates (beware that selectors are generally not
67       * reusable across several {@link EventBasedScheduler instances}, each selector should
68       * be dedicated to one scheduler
69       * @param filter predicate for a posteriori filtering of generated measurements
70       *               (measurements are accepted if the predicates evaluates to {@code true})
71       * @since 13.0
72       */
73      public ContinuousScheduler(final MeasurementBuilder<T> builder, final DatesSelector selector,
74                                 final Predicate<EstimatedMeasurementBase<T>> filter) {
75          super(builder, selector, filter);
76      }
77  
78      /** {@inheritDoc} */
79      @Override
80      public boolean measurementIsFeasible(final AbsoluteDate date) {
81          return true;
82      }
83  
84  
85  }