Quartz.NET开源作业调度框架系列(三):IJobExecutionContext参数传递

2019-11-14 13:42:26

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　　前面写了关于Quartz.NET开源作业调度框架的入门和Cron Trigger , 这次继续这个系列, 这次想讨论一下Quartz.NET中的Job如何通过执行上下文(Execution Contex)进行参数传递 , 有些参数想保存状态该如何处理 . 在Quartz.NET中可以用JobDataMap进行参数传递.本例用Quartz.NET的任务来定期轮询数据库表,当数据库的条目达到一定的数目后,进行预警.(其实可以将读取的表和预警条件配置到数据库中的预警条件表中,这样就可以简单实现一个自动预警提醒的小平台).

1 JobWithParametersExample

 1 using System; 2 using System.Threading; 3  4 using Common.Logging; 5 using Quartz; 6 using Quartz.Impl; 7 using Quartz.Job; 8 using Quartz.Impl.Calendar; 9 using Quartz.Impl.Matchers;10 namespace QuartzDemo11 {12 13     public class JobWithParametersExample 14     {15         public string Name16         {17             get { return GetType().Name; }18         }19         PRivate IScheduler sched = null;20         public JobWithParametersExample(IScheduler _sched)21         {22             sched = _sched;23         }24         public virtual void Run()25         {26             27             //2S后执行28             DateTimeOffset startTime = DateBuilder.NextGivenSecondDate(null, 2);29             IJobDetail job1 = JobBuilder.Create<JobWithParameters>()30                 .WithIdentity("job1", "group1")31                 .Build();32 33             ISimpleTrigger trigger1 = (ISimpleTrigger)TriggerBuilder.Create()34                                                            .WithIdentity("trigger1", "group1")35                                                            .StartAt(startTime)36                                                            .WithSimpleSchedule(x => x.WithIntervalInSeconds(5).WithRepeatCount(100))37                                                            .Build();38 39             // 设置初始参数40             job1.JobDataMap.Put(JobWithParameters.tSQL, "SELECT * FROM [ACT_ID_USER]");41             job1.JobDataMap.Put(JobWithParameters.ExecutionCount, 1);42 43             // 设置监听器44             JobListener listener = new JobListener();45             IMatcher<JobKey> matcher = KeyMatcher<JobKey>.KeyEquals(job1.Key);46             sched.ListenerManager.AddJobListener(listener, matcher);47 48             // 绑定trigger和job49             sched.ScheduleJob(job1, trigger1);50             //启动51             sched.Start();52         53         }54     }55 }

　　JobWithParametersExample用来配置job和trigger,同时定义了一个监听器,来监听定义的job.

2 JobWithParameters

 1 using System; 2 using Common.Logging; 3 using Quartz; 4 using Quartz.Impl; 5 using Quartz.Job; 6 using System.Windows.Forms; 7 namespace QuartzDemo 8 { 9 10     [PersistJobDataAfterExecution]11     [DisallowConcurrentExecution]12     public class JobWithParameters : IJob13     {14     15         // 定义参数常量16         public const string tSQL = "tSQL";17         public const string ExecutionCount = "count";18         public const string RowCount = "rowCount";19         public const string tableAlert = "tAlert"; 20         //  Quartz 每次执行时都会重新实例化一个类, 因此Job类中的非静态变量不能存储状态信息21          private int counter = 1;//都为122         //private static  int counter = 1;//可以保存状态23         public virtual void Execute(IJobExecutionContext context)24         {25            26             JobKey jobKey = context.JobDetail.Key;27             // 获取传递过来的参数            28             JobDataMap data = context.JobDetail.JobDataMap;29             string SQL = data.GetString(tSQL);30             int count = data.GetInt(ExecutionCount);31 32             if (isOpen("FrmConsole"))33             {34                 try35                 {36                     //获取当前Form1实例37                     __instance = (FrmConsole)application.OpenForms["FrmConsole"];38                     //获取当前执行的线程ID39                     __instance.SetInfo(jobKey + "Thread ID " + System.Threading.Thread.CurrentThread.ManagedThreadId.ToString());40                     //数据库操作41                     System.Data.DataTable tAlert = SqlHelper.getDateTable(SQL, null);42                     //回写条数43                     data.Put(RowCount, tAlert.Rows.Count);44                     //通过方法更新消息45                     __instance.SetInfo(string.Format("{0} exec {1} = {2} get {3} rows/r/n           execution count (from job map) is {4}/r/n           execution count (from job member variable) is {5}",46                     jobKey,47                     tSQL,48                     SQL,49                     tAlert.Rows.Count,50                     count, counter));51                     //怎么取出Datatable ? json to datatable52                     //data.Put(tableAlert, tAlert);            53                 }54                 catch (Exception ex)55                 {56                     Console.WriteLine(ex.Message);57                 }58             }59             // 修改执行计数并回写到job data map中60             count++;61             data.Put(ExecutionCount, count);            62             // 修改本地变量,如果是非静态变量,不能存储状态63             counter++;64         }65 66         private static FrmConsole __instance = null;67      68         /// <summary>69         /// 判断窗体是否打开70         /// </summary>71         /// <param name="appName"></param>72         /// <returns></returns>73         private bool isOpen(string appName)74         {75             FormCollection collection = Application.OpenForms;76             foreach (Form form in collection)77             {78                 if (form.Name == appName)79                 {80                     return true;81                 }82             }83             return false;84         }85 86     }87 }

Quartz 每次执行时都会重新实例化一个类, 因此Job类中的非静态变量不能存储状态信息.如何要保存状态信息可以用静态变量进行处理,也可以用参数值进行传入传出来实现.

3 JobListener

 1 using System; 2 using Common.Logging; 3 using Quartz; 4 using Quartz.Impl; 5 using Quartz.Job; 6 namespace QuartzDemo 7 { 8     public class JobListener : IJobListener 9     {10    11         public virtual string Name12         {13             get { return "JobListener"; }14         }15 16         public virtual void JobToBeExecuted(IJobExecutionContext inContext)17         {18             //执行前执行19             Console.WriteLine("JobToBeExecuted");20         }21 22         public virtual void JobExecutionVetoed(IJobExecutionContext inContext)23         {24             //否决时执行25             Console.WriteLine("JobExecutionVetoed");26         }27 28         public virtual void JobWasExecuted(IJobExecutionContext inContext, JobExecutionException inException)29         {30             JobKey jobKey = inContext.JobDetail.Key;31             // 获取传递过来的参数            32             JobDataMap data = inContext.JobDetail.JobDataMap;33             //获取回传的数据库表条目数34             int rowCount = data.GetInt(JobWithParameters.RowCount);35 36             try37             {38                 if (rowCount > 9)39                 {40                     inContext.Scheduler.PauseAll();41                     System.Windows.Forms.MessageBox.Show("预警已超9条");42                     inContext.Scheduler.ResumeAll();43                    44                 }45                 Console.WriteLine(rowCount.ToString());46             }47             catch (SchedulerException e)48             {49              50                 Console.Error.WriteLine(e.StackTrace);51             }52         }53 54     }55 }