1 files changed, 47 insertions, 0 deletions

diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/CountObjective.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/CountObjective.java
new file mode 100644
index 00000000..fbd05ded
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/CountObjective.java
@@ -0,0 +1,47 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.dse.transition.objectives;
+
+import tools.refinery.store.model.Model;
+import tools.refinery.store.model.ModelStore;
+import tools.refinery.store.model.ModelStoreBuilder;
+import tools.refinery.store.query.ModelQueryAdapter;
+import tools.refinery.store.query.ModelQueryBuilder;
+import tools.refinery.store.query.ModelQueryStoreAdapter;
+import tools.refinery.store.query.dnf.RelationalQuery;
+import tools.refinery.store.query.literal.Reduction;
+
+public class CountObjective implements Objective {
+        private final RelationalQuery query;
+        private final double weight;
+
+        public CountObjective(RelationalQuery query) {
+                this(query, 1);
+        }
+
+        public CountObjective(RelationalQuery query, double weight) {
+                this.query = query;
+                this.weight = weight;
+        }
+
+        @Override
+        public boolean isAlwaysZero(ModelStore store) {
+                var queryStore = store.getAdapter(ModelQueryStoreAdapter.class);
+                var canonicalQuery = queryStore.getCanonicalQuery(query);
+                return canonicalQuery.getDnf().getReduction() == Reduction.ALWAYS_FALSE;
+        }
+
+        @Override
+        public ObjectiveCalculator createCalculator(Model model) {
+                var resultSet = model.getAdapter(ModelQueryAdapter.class).getResultSet(query);
+                return () -> resultSet.size() * weight;
+        }
+
+        @Override
+        public void configure(ModelStoreBuilder storeBuilder) {
+                storeBuilder.getAdapter(ModelQueryBuilder.class).query(query);
+        }
+}