001// Copyright 2011 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.tapestry5.ioc.services.cron; 016 017import org.apache.tapestry5.ioc.internal.services.cron.CronExpression; 018 019import java.text.ParseException; 020import java.util.Date; 021 022public class CronSchedule implements Schedule 023{ 024 private CronExpression cron; 025 026 public CronSchedule(String cronExpression) 027 { 028 try 029 { 030 this.cron = new CronExpression(cronExpression); 031 } catch (ParseException e) 032 { 033 throw new RuntimeException(e); 034 } 035 } 036 037 public long firstExecution() 038 { 039 return getNextValidTimeAfterNow(); 040 } 041 042 public long nextExecution(long previousExecution) 043 { 044 return getNextValidTimeAfterNow(); 045 } 046 047 private long getNextValidTimeAfterNow() 048 { 049 final Date time = cron.getNextValidTimeAfter(new Date()); 050 051 return time == null ? 0 : time.getTime(); 052 } 053}