SpringBoot动态定时任务
其实SchedulingConfigurer实现方法很简单，只需要实现SchedulingConfigurer并重写configureTasks方法，在启动类必须加上@EnableScheduling注解即可。
@Configuration
@EnableScheduling
@Slf4j
public class RuleTask implements SchedulingConfigurer {
private volatile ScheduledTaskRegistrar registrar;
private ConcurrentHashMap<Long, ScheduledFuture<?>> scheduledFutures = new ConcurrentHashMap<>();
private ConcurrentHashMap<Long, CronTask> cronTasks = new ConcurrentHashMap<>();
@Override
public void configureTasks(ScheduledTaskRegistrar registrar) {
registrar.setScheduler(Executors.newScheduledThreadPool(30));
this.registrar = registrar;
}
/**
* 刷新任务
* cronList是数据库查出来的定时任务列表
* @param ruleList
*/
public void refresh(List<WarCron> cronList) {
//取消已经删除的任务
Set<Long> cronIds = scheduledFutures.keySet();
for (Long cronId : cronIds) {
if (!exists(cronList, cronId)) {
scheduledFutures.get(cronId).cancel(false);
}
}
if (cronList != null) {
for (WarCron warCron : cronList) {
String expression = warCron.getCron();
//定时任务已存在且表达式未发生变化时跳过
if (scheduledFutures.containsKey(warCron.getCronId()) && cronTasks.get(warCron.getCronId()).getExpression().equals(expression)) {
continue;
}
//如果执行时间发生了变化，则取消当前的定时任务
if (scheduledFutures.containsKey(warCron.getCronId())) {
scheduledFutures.get(warCron.getCronId()).cancel(false);
scheduledFutures.remove(warCron.getCronId());
cronTasks.remove(warCron.getCronId());
}
CronTask task = new CronTask(
new Runnable() {
@Override
public void run() {
System.out.println("------------定时任务--------------");
}
}, warCron.getCron()
);
ScheduledFuture<?> future = registrar.getScheduler().schedule(task.getRunnable(), task.getTrigger());
cronTasks.put(warCron.getCronId(), task);
scheduledFutures.put(warCron.getCronId(), future);
}
}
}
/**
* 判断是否有该任务
*
* @param warCronList
* @param cronId
* @return
*/
private boolean exists(List<WarCron> warCronList, Long cronId) {
for (WarCron warCron : warCronList) {
if (cronId.equals(warCron.getCronId())) {
return true;
}
}
return false;
}
}
每次新增编辑删除数据库中的任务时都需刷新下任务 以达到任务的动态变化
启动boot时也需执行refresh方法;
/**
* @Author: pandar
* @Date: 2021/3/12 0012 上午 11:57
* @Description: 项目启动后刷新定时任务
*/
@Component
public class ApplicationRunnerConfig implements ApplicationRunner {
@Autowired
private RuleTask ruleTask;
@Autowired
private WarCronService warCronService;
@Override
public void run(ApplicationArguments args) throws Exception {
List<WarCron> warCronList = warCronService.selectWarCronAll();
ruleTask.refresh(ruleList);
}
}
数据库表结构
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