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  *      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.apache.commons.math3.optim.linear;
18 
19 import org.apache.commons.math3.optim.OptimizationData;
20 import org.apache.commons.math3.optim.PointValuePair;
21 
22 /**
23  * A callback object that can be provided to a linear optimizer to keep track
24  * of the best solution found.
25  *
26  * @since 3.3
27  */
28 public class SolutionCallback implements OptimizationData {
29     /** The SimplexTableau used by the SimplexSolver. */
30     private SimplexTableau tableau;
31 
32     /**
33      * Set the simplex tableau used during the optimization once a feasible
34      * solution has been found.
35      *
36      * @param tableau the simplex tableau containing a feasible solution
37      */
setTableau(final SimplexTableau tableau)38     void setTableau(final SimplexTableau tableau) {
39         this.tableau = tableau;
40     }
41 
42     /**
43      * Retrieve the best solution found so far.
44      * <p>
45      * <b>Note:</b> the returned solution may not be optimal, e.g. in case
46      * the optimizer did reach the iteration limits.
47      *
48      * @return the best solution found so far by the optimizer, or {@code null} if
49      * no feasible solution could be found
50      */
getSolution()51     public PointValuePair getSolution() {
52         return tableau != null ? tableau.getSolution() : null;
53     }
54 
55     /**
56      * Returns if the found solution is optimal.
57      * @return {@code true} if the solution is optimal, {@code false} otherwise
58      */
isSolutionOptimal()59     public boolean isSolutionOptimal() {
60         return tableau != null ? tableau.isOptimal() : false;
61     }
62 }
63