1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF 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 * https://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
18 /*
19 * This is not the original file distributed by the Apache Software Foundation
20 * It has been modified by the Hipparchus project
21 */
22 package org.hipparchus.optim;
23
24 import java.io.Serializable;
25
26 import org.hipparchus.util.Pair;
27
28 /**
29 * This class holds a point and the value of an objective function at
30 * that point.
31 *
32 * @see PointVectorValuePair
33 * @see org.hipparchus.analysis.MultivariateFunction
34 */
35 public class PointValuePair extends Pair<double[], Double> implements Serializable {
36 /** Serializable UID. */
37 private static final long serialVersionUID = 20120513L;
38
39 /**
40 * Builds a point/objective function value pair.
41 *
42 * @param point Point coordinates. This instance will store
43 * a copy of the array, not the array passed as argument.
44 * @param value Value of the objective function at the point.
45 */
46 public PointValuePair(final double[] point,
47 final double value) {
48 this(point, value, true);
49 }
50
51 /**
52 * Builds a point/objective function value pair.
53 *
54 * @param point Point coordinates.
55 * @param value Value of the objective function at the point.
56 * @param copyArray if {@code true}, the input array will be copied,
57 * otherwise it will be referenced.
58 */
59 public PointValuePair(final double[] point,
60 final double value,
61 final boolean copyArray) {
62 super(copyArray ? ((point == null) ? null :
63 point.clone()) :
64 point,
65 value);
66 }
67
68 /**
69 * Gets the point.
70 *
71 * @return a copy of the stored point.
72 */
73 public double[] getPoint() {
74 final double[] p = getKey();
75 return p == null ? null : p.clone();
76 }
77
78 /**
79 * Gets a reference to the point.
80 *
81 * @return a reference to the internal array storing the point.
82 */
83 public double[] getPointRef() {
84 return getKey();
85 }
86
87 /**
88 * Replace the instance with a data transfer object for serialization.
89 * @return data transfer object that will be serialized
90 */
91 private Object writeReplace() {
92 return new DataTransferObject(getKey(), getValue());
93 }
94
95 /** Internal class used only for serialization. */
96 private static class DataTransferObject implements Serializable {
97 /** Serializable UID. */
98 private static final long serialVersionUID = 20120513L;
99 /**
100 * Point coordinates.
101 * @Serial
102 */
103 private final double[] point;
104 /**
105 * Value of the objective function at the point.
106 * @Serial
107 */
108 private final double value;
109
110 /** Simple constructor.
111 * @param point Point coordinates.
112 * @param value Value of the objective function at the point.
113 */
114 DataTransferObject(final double[] point, final double value) {
115 this.point = point.clone();
116 this.value = value;
117 }
118
119 /** Replace the deserialized data transfer object with a {@link PointValuePair}.
120 * @return replacement {@link PointValuePair}
121 */
122 private Object readResolve() {
123 return new PointValuePair(point, value, false);
124 }
125 }
126 }