/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.cloudstack.framework.events;
import java.util.UUID;
/**
* Interface to publish and subscribe to CloudStack events
*
*/
public interface EventBus {
/**
* publish an event on to the event bus
*
* @param event event that needs to be published on the event bus
*/
void publish(Event event) throws EventBusException;
/**
* subscribe to events that matches specified event topics
*
* @param topic defines category and type of the events being subscribed to
* @param subscriber subscriber that intends to receive event notification
* @return UUID returns the subscription ID
*/
UUID subscribe(EventTopic topic, EventSubscriber subscriber) throws EventBusException;
/**
* unsubscribe to events of a category and a type
*
* @param subscriber subscriber that intends to unsubscribe from the event notification
*/
void unsubscribe(UUID subscriberId, EventSubscriber subscriber) throws EventBusException;
}