1 files changed, 86 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/network/communication/timeless/SingletonCommunicationGroup.java b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/network/communication/timeless/SingletonCommunicationGroup.java
new file mode 100644
index 00000000..c51c7dbf
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+++ b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/network/communication/timeless/SingletonCommunicationGroup.java
@@ -0,0 +1,86 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2019, Tamas Szabo, Istvan Rath 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.network.communication.timeless;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Map;
+
+import tools.refinery.viatra.runtime.rete.network.Node;
+import tools.refinery.viatra.runtime.rete.network.communication.CommunicationGroup;
+import tools.refinery.viatra.runtime.rete.network.communication.CommunicationTracker;
+import tools.refinery.viatra.runtime.rete.network.communication.MessageSelector;
+import tools.refinery.viatra.runtime.rete.network.communication.PhasedSelector;
+import tools.refinery.viatra.runtime.rete.network.mailbox.Mailbox;
+
+/**
+ * A communication group containing only a single node with a single default
+ * mailbox.
+ * 
+ * @author Tamas Szabo
+ * @since 1.6
+ */
+public class SingletonCommunicationGroup extends CommunicationGroup {
+    
+    private Mailbox mailbox;
+
+    /**
+     * @since 1.7
+     */
+    public SingletonCommunicationGroup(final CommunicationTracker tracker, final Node representative, final int identifier) {
+        super(tracker, representative, identifier);
+    }
+
+    @Override
+    public void deliverMessages() {
+        this.mailbox.deliverAll(PhasedSelector.DEFAULT);
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return this.mailbox == null;
+    }
+
+    @Override
+    public void notifyHasMessage(final Mailbox mailbox, final MessageSelector kind) {
+        if (kind == PhasedSelector.DEFAULT) {
+            this.mailbox = mailbox;
+            if (!this.isEnqueued) {
+                this.tracker.activateUnenqueued(this);
+            }
+        } else {
+            throw new IllegalArgumentException(UNSUPPORTED_MESSAGE_KIND + kind);
+        }
+    }
+
+    @Override
+    public void notifyLostAllMessages(final Mailbox mailbox, final MessageSelector kind) {
+        if (kind == PhasedSelector.DEFAULT) {
+            this.mailbox = null;
+            this.tracker.deactivate(this);
+        } else {
+            throw new IllegalArgumentException(UNSUPPORTED_MESSAGE_KIND + kind);
+        }
+    }
+
+    @Override
+    public Map<MessageSelector, Collection<Mailbox>> getMailboxes() {
+        if (mailbox != null) {
+            return Collections.singletonMap(PhasedSelector.DEFAULT, Collections.singleton(mailbox));
+        } else {
+            return Collections.emptyMap();
+        }
+    }
+
+    @Override
+    public boolean isRecursive() {
+        return false;
+    }
+    
+}