| /* |
| * 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.logging.log4j.core.util; |
| |
| import org.apache.logging.log4j.Marker; |
| import org.apache.logging.log4j.MarkerManager; |
| |
| /** |
| * Registry used for Runnable shutdown callback instances. Due to differing requirements of how late in the JVM |
| * lifecycle Log4j should be shut down, this interface is provided for customizing how to register shutdown hook |
| * callbacks. Implementations may optionally implement {@link org.apache.logging.log4j.core.LifeCycle}. |
| * |
| * @since 2.1 |
| */ |
| public interface ShutdownCallbackRegistry { |
| |
| /** |
| * System property to set to choose the ShutdownCallbackRegistry. |
| */ |
| String SHUTDOWN_CALLBACK_REGISTRY = "log4j.shutdownCallbackRegistry"; |
| |
| /** |
| * System property to set to override the global ability to register shutdown hooks. |
| */ |
| String SHUTDOWN_HOOK_ENABLED = "log4j.shutdownHookEnabled"; |
| |
| /** |
| * Shared Marker to indicate log messages corresponding to shutdown hooks. |
| */ |
| Marker SHUTDOWN_HOOK_MARKER = MarkerManager.getMarker("SHUTDOWN HOOK"); |
| |
| /** |
| * Adds a Runnable shutdown callback to this class. |
| * |
| * @param callback the shutdown callback to be executed upon shutdown. |
| * @return a Cancellable wrapper of the provided callback or {@code null} if the shutdown hook is disabled and |
| * cannot be added. |
| * @since 2.1 |
| */ |
| Cancellable addShutdownCallback(Runnable callback); |
| } |