Added unit tests for ParetoSet implementations (#270)

* Changed type of parameter received in methods dedicated to generate lists of TestMove objects, since variable score is a double.

* Added two classes that are useful to implement unit tests in multi-objective contexts. TestSolutionWithMultipleObjectives is similar to TestSolution, but can have more than one objective. TestMoveWithMultipleObjectives is similar to TestMove, but can have more than one objective.

* Changed hashCode method to be consistent with equals.

* Added unit tests for ParetoSimpleList class.

* Removed unnecessary line.

* Added unit tests for ParetoByFirstObjective and NDTree.

* Added MOAlgorithm, needed to define a generic algorithm that returns a ParetoSet instead of a single solution.

common/src/main/java/es/urjc/etsii/grafo/algorithms/mo/MOAlgorithm.java

@@ -0,0 +1,97 @@
+package es.urjc.etsii.grafo.algorithms.mo;
+
+import es.urjc.etsii.grafo.annotations.AlgorithmComponent;
+import es.urjc.etsii.grafo.create.builder.SolutionBuilder;
+import es.urjc.etsii.grafo.io.Instance;
+import es.urjc.etsii.grafo.mo.pareto.ParetoSet;
+import es.urjc.etsii.grafo.solution.Solution;
+
+import java.util.Objects;
+
+
+/**
+ * Base algorithm class, all algorithms should extend this class or any of its subclasses.
+ *
+ * @param <S> Solution class
+ * @param <I> Instance class
+ */
+@AlgorithmComponent
+public abstract class MOAlgorithm<S extends Solution<S,I>, I extends Instance> {
+
+    private SolutionBuilder<S,I> builder;
+    private String algorithmName;
+
+    /**
+     * Initialize common algorithm fields
+     * @param algorithmName algorithm name. See {@link #setName(String)}
+     */
+    protected MOAlgorithm(String algorithmName) {
+        this.algorithmName = algorithmName;
+    }
+
+    /**
+     * Algorithm name, uniquely identifies the algorithm inside an experiment
+     *
+     * @return algorithm name
+     */
+    public String getName(){
+        return this.algorithmName;
+    }
+
+    /**
+     * Sets the algorithm name.
+     * This method can be called after the algorithm has been built,
+     * for example if we want to customize the name generated by the autoconfig module.
+     * This method CANNOT be called after the algorithm has started executing, as it would break the experiment results.
+     * The algorithm name is used to uniquely identify the algorithm inside an experiment.
+     *
+     * @param algorithmName must uniquely identify the algorithm inside an experiment
+     */
+    public void setName(String algorithmName){
+        this.algorithmName = algorithmName;
+    }
+
+    /**
+     * Runs the algorithm
+     *
+     * @param instance Instance to solve
+     * @return Built solution
+     */
+    public abstract ParetoSet<S, I> algorithm(I instance);
+
+    /**
+     * Create a new solution for the given instance. Solution is empty by default.
+     *
+     * @param instance Instance
+     * @return Empty solution, by default created calling the constructor Solution(Instance i)
+     */
+    public S newSolution(I instance){
+        return this.builder.initializeSolution(instance);
+    }
+
+    /**
+     * Get solution builder
+     *
+     * @return solution builder
+     */
+    protected SolutionBuilder<S, I> getBuilder() {
+        return builder;
+    }
+
+    /**
+     * Set solution builder, used by the framework.
+     * In case an algorithms contains another algorithms, this method should be overridden as follows:
+     * <pre>
+     *     &#64;Override
+     *     public void setBuilder(SolutionBuilder&#60;S, I&#62; builder) {
+     *         super.setBuilder(builder);
+     *         this.algorithm.setBuilder(builder);
+     *     }
+     * </pre>
+     *
+     * @param builder solution builder
+     */
+    public void setBuilder(SolutionBuilder<S, I> builder) {
+        this.builder = Objects.requireNonNull(builder);
+    }
+}

common/src/main/java/es/urjc/etsii/grafo/testutil/TestMove.java

@@ -11,11 +11,11 @@ public class TestMove extends Move<TestSolution, TestInstance> {
     private final double score;
     private final FMode fmode;
 
-    public static List<TestMove> generateSeq(int... data){
+    public static List<TestMove> generateSeq(double... data){
         return generateSeq("TestInstance", data);
     }
 
-    public static List<TestMove> generateSeq(String instanceName, int... data){
+    public static List<TestMove> generateSeq(String instanceName, double... data){
         var testInstance = new TestInstance(instanceName);
         var testSolution = new TestSolution(testInstance);
         var moves = new ArrayList<TestMove>();

common/src/main/java/es/urjc/etsii/grafo/testutil/TestMoveWithMultipleObjectives.java

@@ -0,0 +1,98 @@
+package es.urjc.etsii.grafo.testutil;
+
+import es.urjc.etsii.grafo.algorithms.FMode;
+import es.urjc.etsii.grafo.solution.Move;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+
+public class TestMoveWithMultipleObjectives extends Move<TestSolutionWithMultipleObjectives, TestInstance> {
+    private final double[] score;
+    private final FMode[] fmode;
+
+    public static List<TestMoveWithMultipleObjectives> generateSeq(double[]... data){
+        return generateSeq("TestInstance", data);
+    }
+
+    public static List<TestMoveWithMultipleObjectives> generateSeq(String instanceName, double[]... data){
+        var testInstance = new TestInstance(instanceName);
+        var testSolution = new TestSolutionWithMultipleObjectives(testInstance);
+        var moves = new ArrayList<TestMoveWithMultipleObjectives>();
+        for(var i: data){
+            moves.add(new TestMoveWithMultipleObjectives(testSolution, i));
+        }
+        return moves;
+    }
+
+    public TestMoveWithMultipleObjectives(TestSolutionWithMultipleObjectives solution, double[] score, FMode[] fmode) {
+        super(solution);
+        this.score = score;
+        this.fmode = fmode;
+    }
+
+    public TestMoveWithMultipleObjectives(TestSolutionWithMultipleObjectives solution, double[] v) {
+        super(solution);
+        this.score = v;
+        this.fmode = new FMode[v.length];
+        for (int i = 0; i < v.length; i++) {
+            fmode[i] = FMode.MINIMIZE;
+        }
+    }
+
+    @Override
+    protected TestSolutionWithMultipleObjectives _execute(TestSolutionWithMultipleObjectives solution) {
+        int i = 0;
+        for (double v : score) {
+            solution.scores[i] += this.score[i];
+            i++;
+        }
+        return solution;
+    }
+
+    public double[] getScoreChanges() {
+        return score;
+    }
+
+    @Override
+    public String toString() {
+        return "TestMove{" +
+                "score=" + score +
+                ", maximizing=" + fmode +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        TestMoveWithMultipleObjectives testMove = (TestMoveWithMultipleObjectives) o;
+        if (this.score.length != testMove.score.length) {
+            return false;
+        }
+        for (int i = 0; i < this.score.length; i++) {
+            if (Double.compare(testMove.score[i], score[i]) != 0 && fmode[i] != testMove.fmode[i]){
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(Arrays.hashCode(score), Arrays.hashCode(fmode));
+    }
+
+    public boolean isMaximizing(int i) {
+        return fmode.length > i && fmode[i] == FMode.MAXIMIZE;
+    }
+
+    public boolean isMinimizing(int i) {
+        return fmode.length > i && fmode[i] == FMode.MINIMIZE;
+    }
+
+    public FMode[] getFmode() {
+        return fmode;
+    }
+}

common/src/main/java/es/urjc/etsii/grafo/testutil/TestSolutionWithMultipleObjectives.java

@@ -0,0 +1,109 @@
+package es.urjc.etsii.grafo.testutil;
+
+import es.urjc.etsii.grafo.solution.Solution;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.function.Function;
+
+public class TestSolutionWithMultipleObjectives extends Solution<TestSolutionWithMultipleObjectives, TestInstance>{
+
+    protected double[] scores;
+
+    public static TestSolutionWithMultipleObjectives[] from(double... scores) {
+        return from(new TestInstance("TestInstance"), scores);
+    }
+
+    public static TestSolutionWithMultipleObjectives[] from(TestInstance instance, double... scores) {
+        var solutions = new TestSolutionWithMultipleObjectives[scores.length];
+        for (int i = 0; i < scores.length; i++) {
+            solutions[i] = new TestSolutionWithMultipleObjectives(instance, scores);
+        }
+        return solutions;
+    }
+
+    Map<String, Function<TestSolutionWithMultipleObjectives, Object>> properties = new HashMap<>();
+
+
+    public TestSolutionWithMultipleObjectives(TestInstance ins) {
+        super(ins);
+    }
+
+    public TestSolutionWithMultipleObjectives(TestInstance ins, double[] scores) {
+        this(ins);
+        this.scores = scores;
+    }
+
+    public TestSolutionWithMultipleObjectives(TestInstance ins, double[] scores, Map<String, Function<TestSolutionWithMultipleObjectives, Object>> properties) {
+        this(ins);
+        this.scores = scores;
+        this.properties = properties;
+    }
+
+    public TestSolutionWithMultipleObjectives(TestSolutionWithMultipleObjectives sol) {
+        super(sol);
+        this.scores = sol.scores;
+    }
+
+    @Override
+    public TestSolutionWithMultipleObjectives cloneSolution() {
+        return new TestSolutionWithMultipleObjectives(this);
+    }
+
+    @Override
+    public String toString() {
+        return "TestSolutionWithMultipleObjectives{" +
+                "score=" + scores.toString() +
+                '}';
+    }
+
+    public void setTTB(long ttb) {
+        this.lastModifiedTime = ttb;
+    }
+
+    public void resetTTB() {
+        this.lastModifiedTime = Integer.MIN_VALUE;
+    }
+
+
+    @Override
+    public Map<String, Function<TestSolutionWithMultipleObjectives, Object>> customProperties() {
+        return this.properties;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        TestSolutionWithMultipleObjectives that = (TestSolutionWithMultipleObjectives) o;
+        if (this.scores.length != that.scores.length) {
+            return false;
+        }
+        for (int i = 0; i < this.scores.length; i++) {
+            if (Double.compare(that.scores[i], scores[i]) != 0){
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return Arrays.hashCode(this.scores);
+    }
+
+    public void setScores(double[] scores){
+        this.scores = scores;
+    }
+
+    public double getObjective(int index){
+        return this.scores[index];
+    }
+
+    public double[] getScores(){
+        return this.scores;
+    }
+
+}