001/* 002 * Copyright 2002-2012 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.scheduling; 018 019import java.util.Date; 020 021import org.springframework.lang.Nullable; 022 023/** 024 * Common interface for trigger objects that determine the next execution time 025 * of a task that they get associated with. 026 * 027 * @author Juergen Hoeller 028 * @since 3.0 029 * @see TaskScheduler#schedule(Runnable, Trigger) 030 * @see org.springframework.scheduling.support.CronTrigger 031 */ 032public interface Trigger { 033 034 /** 035 * Determine the next execution time according to the given trigger context. 036 * @param triggerContext context object encapsulating last execution times 037 * and last completion time 038 * @return the next execution time as defined by the trigger, 039 * or {@code null} if the trigger won't fire anymore 040 */ 041 @Nullable 042 Date nextExecutionTime(TriggerContext triggerContext); 043 044}