AmbiguityCache.java
/* Copyright 2002-2024 Luc Maisonobe
* Licensed to CS GROUP (CS) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* CS 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.orekit.estimation.measurements.gnss;
import java.util.HashMap;
import java.util.Map;
import org.hipparchus.util.Precision;
/** Cache for {@link AmbiguityDriver}.
* @author Luc Maisonobe
* @since 12.1
*/
public class AmbiguityCache {
/** Default cache.
* @deprecated this default cache is only a temporary hack for compatibility purposes
* it will be removed in Orekit 13.0
*/
@Deprecated
public static final AmbiguityCache DEFAULT_CACHE = new AmbiguityCache();
/** Cache map. */
private final Map<Key, AmbiguityDriver> cache;
/** Simple constructor.
*/
public AmbiguityCache() {
cache = new HashMap<>();
}
/** Get a cached driver for ambiguity.
* <p>
* A new parameter driver is created and cached the first time an
* emitter/receiver/wavelength triplet is used; after that, the cached
* driver will be returned when the same triplet is passed again
* </p>
* @param emitter emitter id
* @param receiver receiver id
* @param wavelength signal wavelength
* @return parameter driver for the emitter/receiver/wavelength triplet
*/
public AmbiguityDriver getAmbiguity(final String emitter, final String receiver, final double wavelength) {
final Key key = new Key(emitter, receiver, wavelength);
synchronized (cache) {
return cache.computeIfAbsent(key, k -> new AmbiguityDriver(emitter, receiver, wavelength));
}
}
/** Key for the map. */
private static class Key {
/** Emitter id. */
private final String emitter;
/** Receiver id. */
private final String receiver;
/** Wavelength. */
private final double wavelength;
/** Simple constructor.
* @param emitter emitter id
* @param receiver receiver id
* @param wavelength signal wavelength
*/
Key(final String emitter, final String receiver, final double wavelength) {
this.emitter = emitter;
this.receiver = receiver;
this.wavelength = wavelength;
}
/** {@inheritDoc} */
@Override
public int hashCode() {
return (emitter.hashCode() ^ receiver.hashCode()) ^ Double.hashCode(wavelength);
}
/** {@inheritDoc} */
@Override
public boolean equals(final Object object) {
if (object instanceof Key) {
final Key other = (Key) object;
return emitter.equals(other.emitter) && receiver.equals(other.receiver) &&
Precision.equals(wavelength, other.wavelength, 1);
}
return false;
}
}
}