1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19
20 package org.apache.commons.jcs3.engine.behavior;
21
22 /**
23 * ShutdownObservers can observe ShutdownObservable objects.
24 * The CacheManager is the primary observable that this is intended for.
25 * <p>
26 * Most shutdown operations will occur outside this framework for now. The initial
27 * goal is to allow background threads that are not reachable through any reference
28 * that the cache manager maintains to be killed on shutdown.
29 * </p>
30 * <p>
31 * Perhaps the composite cache itself should be the observable object.
32 * It doesn't make much of a difference. There are some problems with
33 * region by region shutdown. Some auxiliaries are local. They will
34 * need to track when every region has shutdown before doing things like
35 * closing the socket with a lateral.
36 * </p>
37 */
38 public interface IShutdownObservable
39 {
40
41 /**
42 * Registers an observer with the observable object.
43 * @param observer
44 */
45 void registerShutdownObserver( IShutdownObserver observer );
46
47 /**
48 * Deregister the observer with the observable.
49 *
50 * @param observer
51 */
52 void deregisterShutdownObserver( IShutdownObserver observer );
53
54 }