1 files changed, 31 insertions, 0 deletions

diff --git a/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/objectives/Comparators.java b/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/objectives/Comparators.java
new file mode 100644
index 00000000..b1bd9349
--- /dev/null
+++ b/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/objectives/Comparators.java
@@ -0,0 +1,31 @@
+/*******************************************************************************
+ * 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 org.eclipse.viatra.dse.objectives;
+
+import java.util.Comparator;
+
+/**
+ * This helper class holds comparators for objective implementations.
+ * 
+ * @author Andras Szabolcs Nagy
+ *
+ */
+public class Comparators {
+
+    private Comparators() { /*Utility class constructor*/ }
+    
+    public static final Comparator<Double> HIGHER_IS_BETTER = (o1, o2) -> o1.compareTo(o2);
+
+    public static final Comparator<Double> LOWER_IS_BETTER = (o1, o2) -> o2.compareTo(o1);
+    
+    private static final Double ZERO = Double.valueOf(0);
+    
+    public static final Comparator<Double> DIFFERENCE_TO_ZERO_IS_BETTER = (o1, o2) -> ZERO.compareTo(Math.abs(o1)-Math.abs(o2));
+    
+}