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diff --git a/sdnr/wt-odlux/odlux/framework/src/common/event.ts b/sdnr/wt-odlux/odlux/framework/src/common/event.ts
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+/**
+ * ============LICENSE_START========================================================================
+ * ONAP : ccsdk feature sdnr wt odlux
+ * =================================================================================================
+ * Copyright (C) 2019 highstreet technologies GmbH Intellectual Property. All rights reserved.
+ * =================================================================================================
+ * 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.
+ * ============LICENSE_END==========================================================================
+ */
+
+
+/**
+  * Represents an event.
+  * Events enable a class or object to notify other classes or objects when something of interest occurs.
+  * The class that sends (or invokes) the event is called the publisher and the classes that receive (or handle) the event are called subscribers.
+  * 
+  * Objects can create an instances of an Events and offer that Events for other objects to attach to.
+  * Objects who want to be informed about an Event can attach a function (an event handler) to the event which is then called when the event is fired.
+  * 
+  * @template TEventArg Type of the event argument. Use void if the event does not has an argument.
+  */
+export class Event<TEventArg> {
+
+  /**
+   * Creates a new instance of the Event class.
+   */
+  constructor() {
+    this.eventHandlers = new Array<(arg: TEventArg) => void>();
+  }
+
+  /**
+   * Adds an event handler to this event, so that when the event is fired the given event handler function is called.
+   * 
+   * @param eventHandler The event handler function to add to this event.
+   * @throws {Error} Thrown if the given event handler function has already been added to this event.
+   */
+  public addHandler = (eventHandler: (arg: TEventArg) => void): void => {
+    if (this.eventHandlers.indexOf(eventHandler) > -1) {
+      throw new Error("The given event handler is already added to this event.");
+    }
+
+    this.eventHandlers.push(eventHandler);
+  }
+
+  /**
+   * Removes an event handler from this event, so that the given event handler function will not be called anymore when the event is fired.
+   * 
+   * @param eventHandler: The event handler function to remove.
+   * @throws {Error} Thrown if the given event handler function has not been added to this event before.
+   */
+  public removeHandler = (eventHandler: (arg: TEventArg) => void): void => {
+    const index = this.eventHandlers.indexOf(eventHandler);
+    if (!(index > -1)) {
+      throw new Error("The given event handler has not been added to this event yet.");
+    }
+
+    this.eventHandlers.splice(index, 1);
+  }
+
+  /**
+   * Invokes the event and calls all event handler functions currently registered on the event.
+   * 
+   * @param argument The argument for the event. The argument will be passed to all registered event handler functions.
+   */
+  public invoke = (argument?: TEventArg): void => {
+    this.eventHandlers.forEach((eventHandler: (arg?: TEventArg) => void, index: number, array: Array<(arg: TEventArg) => void>): void => {
+      eventHandler(argument);
+    });
+  }
+
+  private eventHandlers: Array<(arg?: TEventArg) => void>;
+
+}