1 files changed, 58 insertions, 0 deletions

diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/objectives/ObjectiveComparatorHelper.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/objectives/ObjectiveComparatorHelper.java
new file mode 100644
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--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/objectives/ObjectiveComparatorHelper.java
@@ -0,0 +1,58 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2015, Andras Szabolcs Nagy, Abel Hegedus, Akos Horvath, Zoltan Ujhelyi and Daniel Varro
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.store.dse.objectives;
+
+import java.util.List;
+
+/**
+ * This class is responsible to compare and sort fitness values.
+ *
+ * @author András Szabolcs Nagy
+ */
+public class ObjectiveComparatorHelper {
+
+        private final List<Objective> objectives;
+
+        public ObjectiveComparatorHelper(List<Objective> objectives) {
+                this.objectives = objectives;
+        }
+
+        /**
+         * Compares two fitnesses based on dominance. Returns -1 if the second parameter {@code o2} is a better
+         * solution ({@code o2} dominates {@code o1}), 1 if the first parameter {@code o1} is better ({@code o1} dominates
+         * {@code o2}) and returns 0 if they are non-dominating each other.
+         */
+        public int compare(Fitness o1, Fitness o2) {
+
+                boolean o1HasBetterFitness = false;
+                boolean o2HasBetterFitness = false;
+
+                for (Objective objective : objectives) {
+                        String objectiveName = objective.getName();
+                        int sgn = objective.getComparator().compare(o1.get(objectiveName), o2.get(objectiveName));
+
+                        if (sgn < 0) {
+                                o2HasBetterFitness = true;
+                        }
+                        if (sgn > 0) {
+                                o1HasBetterFitness = true;
+                        }
+                        if (o1HasBetterFitness && o2HasBetterFitness) {
+                                break;
+                        }
+                }
+                if (o2HasBetterFitness) {
+                } else if (o1HasBetterFitness) {
+                        return 1;
+                }
+
+                return 0;
+
+        }
+}