EventBusImplementation.java

/**
 *  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.isis.applib.services.eventbus;


/**
 * Common interface for all Event Bus implementations.
 *
 * <p>
 *     Defines an (non-pluggable, hard-coded) SPI to the {@link org.apache.isis.applib.services.eventbus.EventBusService},
 *     to allow alternativeimplementations of in-memory event bus to be used.
 * </p>
 *
 * <p>
 *     Currently, there are implementations based on Guava and on the Axon framework.
 * </p>
 */
public interface EventBusImplementation {

    /**
     * For {@link org.apache.isis.applib.services.eventbus.EventBusService} to call on
     * {@link org.apache.isis.applib.services.eventbus.EventBusService#register(Object)}.
     */
    void register(Object domainService);

    /**
     * For {@link org.apache.isis.applib.services.eventbus.EventBusService} to call on
     * {@link org.apache.isis.applib.services.eventbus.EventBusService#unregister(Object)}.
     */
    void unregister(Object domainService);

    /**
     * For {@link org.apache.isis.applib.services.eventbus.EventBusService} to call on
     * {@link org.apache.isis.applib.services.eventbus.EventBusService#post(Object)}.
     */
    void post(Object event);

}