Added agglink null topology to test aggregate links.

Change-Id: Iba442e5da925f4c065538eff4f71a856670ffc75

+/*
+ * 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.provider.nil;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+/**
+ * Simple triangle topology with multiple links between same devices.
+ */
+public class AggLinkTopologySimulator extends CentipedeTopologySimulator {
+
+    @Override
+    protected void processTopoShape(String shape) {
+        super.processTopoShape(shape);
+        infrastructurePorts = 2 * deviceCount - 1;
+    }
+
+    @Override
+    public void setUpTopology() {
+        checkArgument(deviceCount > 2, "There must be at least 3 devices");
+        super.setUpTopology();
+    }
+
+    @Override
+    protected void createLinks() {
+        int srcPortOffset = deviceCount + 1;
+        for (int i = 0, n = deviceCount; i < n; i++) {
+            int dstPortOffset = 1;
+            for (int j = 0; j <= i; j++) {
+                createLink(i, (i + 1) % n, srcPortOffset + j, dstPortOffset + j);
+            }
+            srcPortOffset = dstPortOffset + i + 1;
+        }
+    }
+
+}

@@ -323,6 +323,8 @@ public class NullProviders {
             return new RerouteTopologySimulator();
         } else if (topoShape.matches("tree([,].*|$)")) {
             return new TreeTopologySimulator();
+        } else if (topoShape.matches("agglink([,].*|$)")) {
+            return new AggLinkTopologySimulator();
         } else if (topoShape.matches("spineleaf([,].*|$)")) {
             return new SpineLeafTopologySimulator();
         } else if (topoShape.matches("mesh([,].*|$)")) {