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 */ 017package org.apache.camel; 018 019/** 020 * A {@link Service} which is also capable of suspending and resuming. 021 * <p/> 022 * This is useable for services which needs more fine grained control at runtime supporting suspension. 023 * Other services may select to mimic suspending by just stopping the service. 024 * <p/> 025 * For example this is use by the JmsConsumer which suspends the Spring JMS listener instead of stopping 026 * the consumer totally. 027 * <p/> 028 * <b>Important:</b> The service should also implement the {@link Suspendable} marker interface to indicate 029 * the service supports suspension using custom code logic. 030 * 031 * @see Suspendable 032 */ 033public interface SuspendableService extends Service { 034 035 /** 036 * Suspends the service. 037 * 038 * @throws Exception is thrown if suspending failed 039 */ 040 void suspend() throws Exception; 041 042 /** 043 * Resumes the service. 044 * 045 * @throws Exception is thrown if resuming failed 046 */ 047 void resume() throws Exception; 048 049 /** 050 * Tests whether the service is suspended or not. 051 * 052 * @return <tt>true</tt> if suspended 053 */ 054 boolean isSuspended(); 055}