001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 018package org.apache.commons.daemon; 019 020/** 021 * Tags a Daemon as supporting some kind of 022 * signalling method that allows the Java application to 023 * perform a custom action. 024 * <p> 025 * User must implement a signal method that will be called from 026 * native upon receiving {@code SIGUSR2} signal from the operating system. 027 * </p> 028 */ 029public interface DaemonUserSignal 030{ 031 032 /** 033 * Performs a custom action on received user signal. 034 */ 035 void signal(); 036 037}