1 files changed, 41 insertions, 0 deletions

diff --git a/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/QueryObjective.java b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/QueryObjective.java
new file mode 100644
index 00000000..5a7ba8f4
--- /dev/null
+++ b/subprojects/store-dse/src/main/java/tools/refinery/store/dse/transition/objectives/QueryObjective.java
@@ -0,0 +1,41 @@
+/*
+ * 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.ModelStoreBuilder;
+import tools.refinery.store.query.ModelQueryAdapter;
+import tools.refinery.store.query.ModelQueryBuilder;
+import tools.refinery.store.query.dnf.FunctionalQuery;
+
+public class QueryObjective implements Objective {
+        protected final FunctionalQuery<? extends Number> objectiveFunction;
+
+        public QueryObjective(FunctionalQuery<? extends Number> objectiveFunction) {
+                if (objectiveFunction.arity() != 0) {
+                        throw new IllegalArgumentException("Objective functions must have 0 parameters, got %d instead"
+                                        .formatted(objectiveFunction.arity()));
+                }
+                this.objectiveFunction = objectiveFunction;
+        }
+
+        @Override
+        public ObjectiveCalculator createCalculator(Model model) {
+                var resultSet = model.getAdapter(ModelQueryAdapter.class).getResultSet(objectiveFunction);
+                return () -> {
+                        var cursor = resultSet.getAll();
+                        if (!cursor.move()) {
+                                return 0;
+                        }
+                        return Math.max(cursor.getValue().doubleValue(), 0);
+                };
+        }
+
+        @Override
+        public void configure(ModelStoreBuilder storeBuilder) {
+                storeBuilder.getAdapter(ModelQueryBuilder.class).query(objectiveFunction);
+        }
+}