使用java.util.concurrent.ScheduledExecutorService结合Spring实现quartz的cron配置
程序员文章站
2022-03-09 08:33:18
...
java的几种定时任务的比较:几种任务调度java实现方案
我最近看了spring的定时任务源码,发现可以使用ScheduledExecutor来实现quartz的cron表达式的配置。并且我加入了可以通过页面修改和配置cron表达式来达到更灵活的配置。
加入的功能如下:
1、开启和关闭任务
2、修改cron表达式并自动重新发布任务
3、基于注解的配置
4、任务持久化到数据库
Spring容器启动时扫描所有被注解的方法,并发布需要启动的任务(代码48行):
@Component public class TaskConfig implements BeanPostProcessor, ApplicationContextAware, ApplicationListener<ContextRefreshedEvent> { private ApplicationContext applicationContext; private Set<JobDetail> jobDetails = new HashSet<JobDetail>(); @Override public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException { return bean; } @Override public Object postProcessAfterInitialization(final Object bean, String beanName) throws BeansException { if (!bean.getClass().getCanonicalName().startsWith("com.xxx.task")) { return bean; } final Class<?> targetClass = AopUtils.getTargetClass(bean); ReflectionUtils.doWithMethods(targetClass, new ReflectionUtils.MethodCallback() { public void doWith(Method method) throws IllegalArgumentException, IllegalAccessException { Job annotation = AnnotationUtils.getAnnotation(method, Job.class); if (annotation != null) { JobDetail job = new JobDetail(); job.setCronExp(annotation.cron()); job.setJobClass(bean.getClass()); job.setJobName(annotation.name()); job.setValid(true); job.setMethodName(method.getName()); jobDetails.add(job); } } }); return bean; } @Override public void onApplicationEvent(ContextRefreshedEvent event) { if (event.getApplicationContext() != this.applicationContext) { return; } for (JobDetail job : jobDetails) { JobService jobService = applicationContext.getBean(JobService.class); JobDetail jobDetail = jobService.findJobByName(job.getJobName()); if (jobDetail == null) { jobDetail = job; } jobService.schedule(jobDetail); } } @Override public void setApplicationContext(ApplicationContext applicationContext) throws BeansException { this.applicationContext = applicationContext; } }
再来jobService的:
@Service public class JobService { private TaskScheduler taskScheduler = new ConcurrentTaskScheduler(Executors.newScheduledThreadPool(1)); private final Map<String, ScheduledFuture<?>> scheduledFutures = new HashMap<String, ScheduledFuture<?>>(); /** * 保存jobName与task的映射关系,等 */ private Map<String, Runnable> runnableMap = new ConcurrentHashMap<String, Runnable>(); private TriggerContext triggerContext = new SimpleTriggerContext(); /** * 根据jobDetail计划一次新的任务 * 任务执行完毕自动计算下次任务执行时间并保存 * @param job */ @Transactional public void schedule(final JobDetail job) { CronTrigger trigger = new CronTrigger(job.getCronExp()); final CronSequenceGenerator sequenceGenerator = new CronSequenceGenerator(job.getCronExp(), TimeZone.getDefault()); job.setNextExecTime(sequenceGenerator.next(new Date())); commonDao.saveOrUpdate(job); ErrorHandler errorHandler = new JobErrorHandler(job); Runnable runnable = new Runnable() { @Override public void run() { // 每一次执行任务都需要获取最新的任务状态 JobDetail currentJob = findJobByName(job.getJobName()); if (currentJob != null && currentJob.isValid()) { Object o = SpringContextUtil.getBean(currentJob.getJobClass()); ReflectionUtils.invokeMethod(ReflectionUtils.findMethod(currentJob.getJobClass(), currentJob.getMethodName()), o); Date d = new Date(); currentJob.setLastExecTime(d); currentJob.setNextExecTime(sequenceGenerator.next(new Date())); commonDao.saveOrUpdate(currentJob); } else { cancel(job.getJobName()); } } }; Runnable delegatingErrorHandlingRunnable = TaskUtils.decorateTaskWithErrorHandler(runnable, errorHandler, false); this.scheduledFutures.put(job.getJobName(), taskScheduler.schedule(delegatingErrorHandlingRunnable, trigger)); } /** * 停止任务 * @param jobName */ @Transactional public void stopJob(String jobName) { String update = "update cms_sys_jobdetails set VALID='N' where JOB_NAME='" + jobName + "'"; commonDao.getCurrentSession().createSQLQuery(update).executeUpdate(); this.cancel(jobName); } /** * 结束任务 * @param jobName */ @Transactional public void startJob(String jobName) { JobDetail job = this.findJobByName(jobName); job.setValid(true); this.schedule(job); } /** * 重置cron表达式 * @param jobName * @param cron */ @Transactional public void resetCron(String jobName, String cron) { new CronSequenceGenerator(cron, TimeZone.getDefault()); JobDetail job = this.findJobByName(jobName); job.setCronExp(cron); commonDao.saveOrUpdate(job); if (job.isValid()) { this.cancel(jobName); this.schedule(job); } } /** * 取消未执行的任务 * @param jobName */ private void cancel(String jobName) { ScheduledFuture r = scheduledFutures.get(jobName); if (r != null) { r.cancel(true); //参数true表示如果任务正在执行,则强行关闭,否则等待执行完毕关闭 } } /** * 任务处理失败时的ErrorHandler */ private class JobErrorHandler implements ErrorHandler { private JobDetail job; public JobErrorHandler(JobDetail job) { this.job = job; } private final Log logger = LogFactory.getLog(JobErrorHandler.class); @Override public void handleError(Throwable t) { logger.error("Unexpected error occurred in scheduled task===>" + job.getJobName(), t); } } }
JobDetai是需要持久化到数据库的实体:
@Entity @Table(name = "CMS_SYS_JOBDETAILS") public class JobDetail implements Serializable { private static final long serialVersionUID = 6899388713399265016L; @Id @GeneratedValue(strategy = GenerationType.SEQUENCE) private Long id; @Column(name="JOB_NAME", length = 255) private String jobName; @Column(name="CRON_EXP", length = 255) private String cronExp; @Column(name = "LAST_EXEC_TIME") @Temporal(TemporalType.TIMESTAMP) private Date lastExecTime; @Column(name = "NEXT_EXEC_TIME") @Temporal(TemporalType.TIMESTAMP) private Date nextExecTime; @Type(type = "yes_no") @Column(name = "VALID") private boolean valid; @Column(name = "JOB_CLASS") private Class jobClass; @Column(name = "METHOD_NAME") private String methodName; public String getMethodName() { return methodName; } public void setMethodName(String methodName) { this.methodName = methodName; } public Class getJobClass() { return jobClass; } public void setJobClass(Class jobClass) { this.jobClass = jobClass; } public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getJobName() { return jobName; } public void setJobName(String jobName) { this.jobName = jobName; } public String getCronExp() { return cronExp; } public void setCronExp(String cronExp) { this.cronExp = cronExp; } public Date getLastExecTime() { return lastExecTime; } public void setLastExecTime(Date lastExecTime) { this.lastExecTime = lastExecTime; } public Date getNextExecTime() { return nextExecTime; } public boolean isValid() { return valid; } public void setValid(boolean valid) { this.valid = valid; } public void setNextExecTime(Date nextExecTime) { this.nextExecTime = nextExecTime; } }
自定义注解Job,可以加在所有需要定时任务的方法上
/** * 用来注解所有需要做定时任务的方法,name和cron是必填项,分别代表任务名称和任务的cron * 加了这个注解的方法在被加载到spring上下文时会被{@link TaskConfig}拦截并将所有的配置 * 信息加载到数据库里面,接着初始化所有的定时任务。定时任务所有的对外暴露的API都被放到了 * {@link com.xxx.service.JobService}里面了。 * * @see com.xxx.service.JobService * @see TaskConfig * @author: bigtian * Date: 12-6-20 * Time: 下午7:26 */ @Target({ ElementType.TYPE, ElementType.METHOD }) @Retention(RetentionPolicy.RUNTIME) public @interface Job { String name(); String cron(); }
上一篇: 美团优选新人怎么免费领东西?美团优选获取新人礼包方法
下一篇: C 语言基础之初识 C 语言常量
推荐阅读
-
Spring 使用JavaConfig实现配置的方法步骤
-
基于spring JdbcTemplate的扩展,结合velocity模板实现sql语句的可配置可动态添加
-
基于spring JdbcTemplate的扩展,结合velocity模板实现sql语句的可配置可动态添加
-
Spring 使用JavaConfig实现配置的方法步骤
-
spring学习之六“AOP使用spring静态配置文件的实现”
-
java定时任务_Spring Boot 整合 Quartz 实现 Java 定时任务的动态配置
-
基于Spring的最简单的定时任务实现与配置之cron表达式的相关内容
-
spring创建项目xml文件的配置以及使用spring+c3p0连接池+jsp、servlet+elementUI+Vue简单实现学生管理系统的增删改查
-
定时器的实现、java定时器Timer和Quartz介绍与Spring中定时器的配置
-
结合SpEL使用@Value-基于配置文件或非配置的文件的值注入-Spring Boot