1 files changed, 90 insertions, 0 deletions
diff --git a/framework/src/onos/core/api/src/main/java/org/onosproject/ui/topo/BiLinkMap.java b/framework/src/onos/core/api/src/main/java/org/onosproject/ui/topo/BiLinkMap.java
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+++ b/framework/src/onos/core/api/src/main/java/org/onosproject/ui/topo/BiLinkMap.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.onosproject.ui.topo;
+
+import org.onosproject.net.Link;
+import org.onosproject.net.LinkKey;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Represents a collection of {@link BiLink} concrete classes. These maps
+ * are used to collate a set of unidirectional {@link Link}s into a smaller
+ * set of bi-directional {@link BiLink} derivatives.
+ * <p>
+ * @param <B> the type of bi-link subclass
+ */
+public abstract class BiLinkMap<B extends BiLink> {
+
+    private final Map<LinkKey, B> map = new HashMap<>();
+
+    /**
+     * Creates a new instance of a bi-link. Concrete subclasses should
+     * instantiate and return the appropriate bi-link subclass.
+     *
+     * @param key the link key
+     * @param link the initial link
+     * @return a new instance
+     */
+    protected abstract B create(LinkKey key, Link link);
+
+    /**
+     * Adds the given link to our collection, returning the corresponding
+     * bi-link (creating one if needed necessary).
+     *
+     * @param link the link to add to the collection
+     * @return the corresponding bi-link wrapper
+     */
+    public B add(Link link) {
+        LinkKey key = TopoUtils.canonicalLinkKey(checkNotNull(link));
+        B blink = map.get(key);
+        if (blink == null) {
+            // no bi-link yet exists for this link
+            blink = create(key, link);
+            map.put(key, blink);
+        } else {
+            // we have a bi-link for this link.
+            if (!blink.one().equals(link)) {
+                blink.setOther(link);
+            }
+        }
+        return blink;
+    }
+
+    /**
+     * Returns the bi-link instances in the collection.
+     *
+     * @return the bi-links in this map
+     */
+    public Collection<B> biLinks() {
+        return map.values();
+    }
+
+    /**
+     * Returns the number of bi-links in the collection.
+     *
+     * @return number of bi-links
+     */
+    public int size() {
+        return map.size();
+    }
+}