• Quartz与Spring整合进行热部署的实现


    先来几张实现图

    任务管理页.

    新建任务管理.目前实现叫简单的需求...若各位同学要实现复杂的设计...quartz都有提供强大的支持.小弟目前的需求做到这已经够用了.

    接下来.我们如何实现quartz的热部署编码呢?

    小弟是利用spring整合quzrtz实现的.但是会产生两个小问题.

    我们先看看quartz如何与spring整合

    <bean name="quartzScheduler" class="org.springframework.scheduling.quartz.SchedulerFactoryBean">
    <property name="dataSource" ref="dataSource"/>
    <property name="applicationContextSchedulerContextKey" value="applicationContextKey"/>
    <property name="configLocation" value="classpath:quartz.properties"/><!--
    这个是必须的,QuartzScheduler 延时启动,应用启动完后 QuartzScheduler 再启动
    -->
    <property name="startupDelay" value="30"/><!--
    这个是可选,QuartzScheduler 启动时更新己存在的Job,这样就不用每次修改targetObject后删除qrtz_job_details表对应记录了
    -->
    <property name="overwriteExistingJobs" value="true"/>
    <property name="jobDetails" >
    <list>
    <ref bean="xxxJobDetail"/>

    </list>
    </property>
    </bean>

    首先.我们需要添加一个数据源给quzrtz.允许其序列化JobDetail到数据库.之后有注释.呵呵.我就不必多说了.

    <bean id="xxxJobDetail" class="frameworkx.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean">
    <!--shouldRecover属性为true,则当Quartz服务被中止后,再次启动任务时会尝试恢复执行之前未完成的所有任务-->
    <!--<property name="shouldRecover" value="true"/>-->
    <!-- 标识job是持久的,删除触发器的时候不被删除 -->
    <property name="durable" value="true"/>
    <property name="targetObject" ref="xxxxJob"/>
      
    <!-- 此处是需要执行的任务的方法 -->
    <property name="targetMethod" value="executeJob"/>
    </bean>

    凡是使用过quartz跟spring整合的同学会发现.为什么class的命名空间不是org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean呢?

    因为spring技术小组的class会报NotSerializableException.且功能不强shouldRecover,durable这些基础属性不提供...大概spring的MethodInvokingJobDetailFactoryBean根本不支持JobDetail的序列化...想详细了解原因.可以看spring的源码.目前小弟使用的spring3,spring小组依然没解决这问题,应该说还不支持JobDetail序列化.但国外牛人们已经帮我们解决好了.详细见下连接

    http://jira.springframework.org/browse/SPR-3797

    好了.接下来我们需要配置quzrtz的properties(放到classpath下.quzrtz就能找到)

    org.quartz.scheduler.instanceName = DefaultQuartzScheduler
    org.quartz.scheduler.rmi.export
    = false
    org.quartz.scheduler.rmi.proxy
    = false
    org.quartz.scheduler.wrapJobExecutionInUserTransaction
    = false

    org.quartz.threadPool.
    class = org.quartz.simpl.SimpleThreadPool
    org.quartz.threadPool.threadCount
    = 10
    org.quartz.threadPool.threadPriority
    = 5
    org.quartz.threadPool.threadsInheritContextClassLoaderOfInitializingThread
    = true

    org.quartz.jobStore.misfireThreshold
    = 60000

    #org.quartz.jobStore.
    class = org.quartz.simpl.RAMJobStore

    org.quartz.jobStore.
    class = org.quartz.impl.jdbcjobstore.JobStoreTX
    #org.quartz.jobStore.driverDelegateClass
    =org.quartz.impl.jdbcjobstore.HSQLDBDelegate
    org.quartz.jobStore.driverDelegateClass
    =org.quartz.impl.jdbcjobstore.StdJDBCDelegate
    #org.quartz.jobStore.useProperties
    = true
    org.quartz.jobStore.tablePrefix
    = QRTZ_
    org.quartz.jobStore.isClustered
    = false
    org.quartz.jobStore.maxMisfiresToHandleAtATime
    =1

    我们这次是选择org.quartz.jobStore.class = org.quartz.impl.jdbcjobstore.JobStoreTX

    而不是默认的org.quartz.jobStore.class = org.quartz.simpl.RAMJobStore简单存储在内存中.

    接来下,我们需要一个quartz的scheduler管理类.

    protected final Log log = LogFactory.getLog(getClass());
    private Scheduler scheduler;
    private QuartzDao quartzDao;

    private static final Logger logger = LoggerFactory.getLogger(SchedulerServiceImpl.class);



    public void setScheduler(Scheduler scheduler) {
    this.scheduler = scheduler;
    }


    public void setQuartzDao(QuartzDao quartzDao) {
    this.quartzDao = quartzDao;
    }

    /**
    * 根据job的名称获取job,进而添加到trigger
    *
    @param name
    *
    @param jobName
    *
    @param cronExpression
    *
    @param group
    *
    @throws SchedulerException
    */

    public void schedule(String name, String jobName, String cronExpression,String group) throws SchedulerException {
    if (name == null || name.trim().equals("")) {
    name
    = UUID.randomUUID().toString();
    }

    try {
    JobDetail jobDetail
    = scheduler.getJobDetail(jobName, group);

    if(jobDetail != null) {
    scheduler.addJob(jobDetail,
    true);

    CronTrigger cronTrigger
    = new CronTrigger(name, group, jobDetail.getName(),
    Scheduler.DEFAULT_GROUP);
    cronTrigger.setCronExpression(
    new CronExpression(cronExpression));
    scheduler.scheduleJob(cronTrigger);
    scheduler.rescheduleJob(cronTrigger.getName(), cronTrigger.getGroup(), cronTrigger);
    }
    else
    log.error(
    "无法找到对应的job.所以无法建立trigger");


    }
    catch (SchedulerException e) {
    log.error(e.getMessage());
    throw new SchedulerException();
    }
    catch (ParseException e) {
    log.error(e.getMessage());
    }
    }

    public List<Map<String, Object>> getQrtzTriggers(){
    return quartzDao.getQrtzTriggers();
    }


    public void pauseTrigger(String triggerName,String group) throws SchedulerException{
    try {
    scheduler.pauseTrigger(triggerName, group);
    //停止触发器
    } catch (SchedulerException e) {
    log.error(e.getMessage());
    throw new SchedulerException();
    }
    }


    public void resumeTrigger(String triggerName,String group) throws SchedulerException{
    try {
    scheduler.resumeTrigger(triggerName, group);
    //重启触发器
    } catch (SchedulerException e) {
    log.error(e.getMessage());
    throw new SchedulerException();
    }
    }


    public boolean removeTrigdger(String triggerName,String group) throws SchedulerException{
    try {

    scheduler.pauseTrigger(triggerName, group);
    //停止触发器
    return scheduler.unscheduleJob(triggerName, group);//移除触发器
    } catch (SchedulerException e) {
    log.error(e.getMessage());
    throw new SchedulerException();
    }
    }


    public String[] getJobNames(String group) throws SchedulerException {
    String[] jobNames
    = null;
    try {
    jobNames
    = scheduler.getJobNames(group);
    }
    catch (SchedulerException e) {
    log.error(e.getMessage());
    throw new SchedulerException();
    }
    return jobNames;
    }

    但前只是简单实现通过cornexpression.若有复杂配置trigger规则的.或需要对trigger添加calendar...可以自己进行扩展.

    一下是quzrtzDao的实现

    private DataSource dataSource;

    public void setDataSource(DataSource dataSource) {
    this.dataSource = dataSource;
    }

    public List<Map<String, Object>> getQrtzTriggers() {
    List
    <Map<String, Object>> results = getJdbcTemplate().queryForList("select * from QRTZ_TRIGGERS order by start_time");
    long val = 0;
    String temp
    = null;
    for (Map<String, Object> map : results) {
    temp
    = MapUtils.getString(map, "trigger_name");
    if(StringUtils.indexOf(temp, "#") != -1){
    map.put(
    "display_name", StringUtils.substringBefore(temp, "#"));
    }
    else{
    map.put(
    "display_name", temp);
    }

    val
    = MapUtils.getLongValue(map, "next_fire_time");
    if (val > 0) {
    map.put(
    "next_fire_time", DateFormatUtils.format(val, "yyyy-MM-dd HH:mm:ss"));
    }

    val
    = MapUtils.getLongValue(map, "prev_fire_time");
    if (val > 0) {
    map.put(
    "prev_fire_time", DateFormatUtils.format(val, "yyyy-MM-dd HH:mm:ss"));
    }

    val
    = MapUtils.getLongValue(map, "start_time");
    if (val > 0) {
    map.put(
    "start_time", DateFormatUtils.format(val, "yyyy-MM-dd HH:mm:ss"));
    }

    val
    = MapUtils.getLongValue(map, "end_time");
    if (val > 0) {
    map.put(
    "end_time", DateFormatUtils.format(val, "yyyy-MM-dd HH:mm:ss"));
    }

    map.put(
    "statu",status.get(MapUtils.getString(map, "trigger_state")));
    }

    return results;
    }


    public static final Map<String,String> status = new HashMap<String,String>();


    static{
    status.put(
    "ACQUIRED", "运行");
    status.put(
    "PAUSED", "暂停");
    status.put(
    "WAITING", "等待");

    }

    private JdbcTemplate getJdbcTemplate() {
    return new JdbcTemplate(this.dataSource);
    }

    同学们可以根据自己的风格,修改一下其代码.

    此时我们就可以创建一个简单的quzrtz的热部署管理.

    我之前讲过会有两个问题.第二个问题是什么呢?还记得讲过我们需要讲jobDetail序列化到数据库吗?因为我们使用了spring 系统中的manager类通过spring的IOC依赖注入.那我们的跟quartz相关的manager都需要声明实现Serializable序列化接口.

    此时我们可以想到用ContextLoader.getCurrentWebApplicationContext()把相应的manage通过bean id get出来.

    public class SpringBeanProvide implements Serializable/*, ApplicationContextAware*/{


    /**
    *
    */
    private static final long serialVersionUID = 8430477279431126488L;
    private ApplicationContext context;

    @SuppressWarnings(
    "unchecked")
    public <T> T getBean(Class<T> clazz, String beanName){
    context
    = ContextLoader.getCurrentWebApplicationContext();
    return (T)context.getBean(beanName);
    }

    public ServletContext getServletContext() {
    WebApplicationContext webContext
    = ContextLoader.getCurrentWebApplicationContext();
    return webContext.getServletContext();
    }

    /*@Autowired
    public void setApplicationContext(ApplicationContext context)
    throws BeansException {
    this.context = context;

    }
    */
    }

    我们看看ContextLoader.getCurrentWebApplicationContext()的源码

    /**
    * Obtain the Spring root web application context for the current thread
    * (i.e. for the current thread's context ClassLoader, which needs to be
    * the web application's ClassLoader).
    *
    @return the current root web application context, or <code>null</code>
    * if none found
    *
    @see org.springframework.web.context.support.SpringBeanAutowiringSupport
    */
    public static WebApplicationContext getCurrentWebApplicationContext() {
    ClassLoader ccl
    = Thread.currentThread().getContextClassLoader();
    if (ccl != null) {
    WebApplicationContext ccpt
    = currentContextPerThread.get(ccl);
    if (ccpt != null) {
    return ccpt;
    }
    }
    return currentContext;
    }

    currentContextPerThread是一个final的ConcurrentHashMap.也是IOC容器存储bean的一个hash表.

    到底什么时候才把ccl设置到currentContextPerThread中呢?

    我们往上看源码

    try {
    // Determine parent for root web application context, if any.
    ApplicationContext parent = loadParentContext(servletContext);

    // Store context in local instance variable, to guarantee that
    // it is available on ServletContext shutdown.
    this.context = createWebApplicationContext(servletContext, parent);
    servletContext.setAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE,
    this.context);

    ClassLoader ccl
    = Thread.currentThread().getContextClassLoader();
    if (ccl == ContextLoader.class.getClassLoader()) {
    currentContext
    = this.context;
    }
    else if (ccl != null) {
    currentContextPerThread.put(ccl,
    this.context);
    }
    其中...currentContextPerThread.put(ccl, this.context);是在ApplicationContext parent = loadParentContext(servletContext);之下.

    ContextLoader.getCurrentWebApplicationContext()只能在容器完全初始化后才能使用..这对于单元测试时...ccpt返回出来的是一个null...

    这就是我为什么会在SpringBeanProvide出现注释了ApplicationContextAware的原因...因为本人有点懒...哈哈..没重新整理一份spring的bean xml作为单元测试使用...所以...在单元测试时...改一下注释...就去跑了..呵呵...此时...我们已经可以使用quzrtz的热部署.不必重启服务器就可以对任务进行管理了.

    以上的实现.参考了javaeye中的部分文章.

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  • 原文地址:https://www.cnblogs.com/pigwing/p/2005158.html
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