VOL-2710: Add unit test cases for kafka-onos

Change-Id: Ieff0a32b3552eb8843fa933e57fa4148cb54853b
diff --git a/src/test/java/org/opencord/kafka/integrations/McastKafkaIntegrationTest.java b/src/test/java/org/opencord/kafka/integrations/McastKafkaIntegrationTest.java
new file mode 100644
index 0000000..135239a
--- /dev/null
+++ b/src/test/java/org/opencord/kafka/integrations/McastKafkaIntegrationTest.java
@@ -0,0 +1,96 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.opencord.kafka.integrations;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.onlab.packet.VlanId;
+import org.opencord.cordmcast.CordMcastStatisticsEventListener;
+import org.opencord.cordmcast.CordMcastStatisticsService;
+import org.opencord.kafka.EventBusService;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * set of unit test cases for McastKafkaIntegration.
+ */
+public class McastKafkaIntegrationTest extends KafkaIntegrationTestBase {
+    private McastKafkaIntegration mcastKafkaIntegration;
+    private CordMcastStatisticsEventListener mcastStatsListerner;
+
+    @BeforeEach
+    void setup() {
+        mcastKafkaIntegration = new McastKafkaIntegration();
+        mcastKafkaIntegration.eventBusService = new MockEventBusService();
+        mcastKafkaIntegration.cordMcastStatisticsService = new MockCordMcastStatisticsService();
+        mcastKafkaIntegration.bindMcastStatisticsService(mcastKafkaIntegration.cordMcastStatisticsService);
+        mcastKafkaIntegration.activate();
+    }
+
+    @AfterEach
+    void tearDown() {
+        mcastKafkaIntegration.unbindMcastStatisticsService(mcastKafkaIntegration.cordMcastStatisticsService);
+        mcastKafkaIntegration.deactivate();
+    }
+
+    /**
+     * test to verify CordMcastStatisticsEvent event.
+     */
+    @Test
+    void testHandleEvent() {
+        mcastStatsListerner.event(getCordMcastStatisticsEvent());
+        assertEquals(MockEventBusService.mcastStats, 1);
+        assertEquals(MockEventBusService.otherCounter, 0);
+
+    }
+
+    private static class MockEventBusService implements EventBusService {
+        static int mcastStats;
+        static int otherCounter;
+
+        MockEventBusService() {
+            mcastStats = 0;
+            otherCounter = 0;
+        }
+
+        @Override
+        public void send(String topic, JsonNode data) {
+            if (topic.equals(McastKafkaIntegration.MCAST_OPERATIONAL_STATUS_TOPIC)) {
+                mcastStats++;
+            } else {
+                otherCounter++;
+            }
+        }
+    }
+
+    private class MockCordMcastStatisticsService implements CordMcastStatisticsService {
+        @Override
+        public void setVlanValue(VlanId vlanId) {
+        }
+
+        @Override
+        public void addListener(CordMcastStatisticsEventListener listener) {
+            mcastStatsListerner = listener;
+        }
+
+        @Override
+        public void removeListener(CordMcastStatisticsEventListener listener) {
+            mcastStatsListerner = null;
+        }
+    }
+}