[ONOS-3117] adding Flow-Classifier event handler

Change-Id: Iad86fc1fafcb1c8da3008e2794f3c91843e50ed2

+/*
+ * 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.vtnrsc.flowclassifier;
+
+import org.onosproject.event.AbstractEvent;
+import org.onosproject.vtnrsc.FlowClassifier;
+
+/**
+ * Describes network Flow-Classifier event.
+ */
+public class FlowClassifierEvent extends AbstractEvent<FlowClassifierEvent.Type, FlowClassifier> {
+    /**
+     * Type of flow-classifier events.
+     */
+    public enum Type {
+        /**
+         * Signifies that flow-classifier has been created.
+         */
+        FLOW_CLASSIFIER_PUT,
+        /**
+         * Signifies that flow-classifier has been deleted.
+         */
+        FLOW_CLASSIFIER_DELETE,
+        /**
+         * Signifies that flow-classifier has been updated.
+         */
+        FLOW_CLASSIFIER_UPDATE
+    }
+
+    /**
+     * Creates an event of a given type and for the specified Flow-Classifier.
+     *
+     * @param type Flow-Classifier event type
+     * @param flowClassifier Flow-Classifier subject
+     */
+    public FlowClassifierEvent(Type type, FlowClassifier flowClassifier) {
+        super(type, flowClassifier);
+    }
+
+    /**
+     * Creates an event of a given type and for the specified Flow-Classifier.
+     *
+     * @param type Flow-Classifier event type
+     * @param flowClassifier Flow-Classifier subject
+     * @param time occurrence time
+     */
+    public FlowClassifierEvent(Type type, FlowClassifier flowClassifier, long time) {
+        super(type, flowClassifier, time);
+    }
+}