1 files changed, 47 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/index/OnetimeIndexer.java b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/index/OnetimeIndexer.java
new file mode 100644
index 00000000..fef84bb1
--- /dev/null
+++ b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/index/OnetimeIndexer.java
@@ -0,0 +1,47 @@
+/*******************************************************************************
+ * Copyright (c) 2004-2008 Gabor Bergmann 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.viatra.runtime.rete.index;
+
+import java.util.Collection;
+
+import tools.refinery.viatra.runtime.matchers.tuple.Tuple;
+import tools.refinery.viatra.runtime.matchers.tuple.TupleMask;
+import tools.refinery.viatra.runtime.rete.network.ReteContainer;
+import tools.refinery.viatra.runtime.rete.network.Supplier;
+
+/**
+ * @author Gabor Bergmann Indexer whose lifetime last until the first get() DO NOT connect to nodes!
+ */
+public class OnetimeIndexer extends GenericProjectionIndexer {
+
+    public OnetimeIndexer(ReteContainer reteContainer, TupleMask mask) {
+        super(reteContainer, mask);
+    }
+
+    @Override
+    public Collection<Tuple> get(Tuple signature) {
+        if (tools.refinery.viatra.runtime.rete.util.Options.releaseOnetimeIndexers) {
+            reteContainer.unregisterClearable(memory);
+            reteContainer.unregisterNode(this);
+        }
+        return super.get(signature);
+    }
+
+    @Override
+    public void appendParent(Supplier supplier) {
+        throw new UnsupportedOperationException("onetime indexer cannot have parents");
+    }
+
+    @Override
+    public void attachListener(IndexerListener listener) {
+        throw new UnsupportedOperationException("onetime indexer cannot have listeners");
+    }
+
+}