* Copyright (c) 2010-2011. Axon Framework
* 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
* 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.
Consider implementing one of the abstract subclasses to categorize events into one of three categories:
: Events that represent a state change of an aggregate.
: Events that do not represent a state change of an aggregate, but do have an important meaning to the application.
: Events that represent a state change or notification of a subsystem. These events typically notify the application that part of it is not available.