Quartz如何设置多任务？
现在想实现这样一个问题：
有多个作业，每个作业的调度时间都不同，我已用Quartz实现了单作业调度，但多作业调度的问题，就不行了，麻烦哪位朋友指点指点。下面是TestDemo：
public class Test_1 { public Scheduler createScheduler() throws Exception { SchedulerFactory sf = new StdSchedulerFactory("Quartz.properties"); Scheduler scheduler = sf.getScheduler(); scheduler.scheduleJob(createJobDetail_1(), createCronTrigger_1());[color=#FF0000]// 下面这一行，是我添加的另外一个作用的调度计划，问题就出在这[/color] scheduler.scheduleJob(createJobDetail_2(), createCronTrigger_2()); return scheduler;}private JobDetail createJobDetail_1() { JobDetail job = new JobDetail(DemoJob_1.class.getName(), Scheduler.DEFAULT_GROUP, DemoJob_1.class); return job;}private CronTrigger createCronTrigger_1() throws ParseException { CronTrigger trigger = new org.quartz.CronTrigger("DEFAULT", null); trigger.setJobName(DemoJob_1.class.getName()); trigger.setCronExpression(" 0/5 * * * * ? "); return trigger;}private JobDetail createJobDetail_2() { JobDetail job = new JobDetail(DemoJob_2.class.getName(), Scheduler.DEFAULT_GROUP, DemoJob_2.class); return job;}private CronTrigger createCronTrigger_2() throws ParseException { CronTrigger trigger = new org.quartz.CronTrigger("DEFAULT", null); trigger.setJobName(DemoJob_2.class.getName()); trigger.setCronExpression(" 0/15 * * * * ? "); return trigger;}} public class DemoJob_1 implements Job { @Override public void execute(JobExecutionContext arg0) throws JobExecutionException { System.out.println("DemoJob_1 demo output :" + new Date()); }}public class DemoJob_2 implements Job { @Override public void execute(JobExecutionContext arg0) throws JobExecutionException { System.out.println("DemoJob_2 demo output :" + new Date()); }}public class DemoTest { public static void main(String [] args) throws SchedulerException, Exception{ Test_1 test_1 = new Test_1(); test_1.createScheduler().start(); }}