Quartz框架的核心是调度器。调度器负责管理Quartz应用运行时环境。调度器不是靠自己做所有的工作，而是依赖框架内一些非常重要的部件。Quartz不仅仅是线程和线程管理。为确保可伸缩性，Quartz采用了基于多线程的架构。启动时，框架初始化一套worker线程，这套线程被调度器用来执行预定的作业。这就是Quartz怎样能并发运行多个作业的原理。Quartz依赖一套松耦合的线程池管理部件来管理线程环境。
该定时器Demo用于定时执行制定路径下的jar包的编译,也可以用于普通的任务调度.通过对任务的查询修改删除来管理整个列表文件.可以通关开启和关闭来更改jar的开始执行状态(开启后如果需要停止只能关闭或重启服务器才能生效,具体的解决办法还在改进中).相关的一整套的UI界面比较简略,可以进行二次开发,主要整合了JPA的分页查询,可以查看相关代码部分.
//主页路径:
http://localhost:9090/
//启动jar的路径(这里的我只是建了一个简单的springboot的helloword的Jar包,相关jar包在项目中可以找到)
http://localhost:8088/sayHello@Service
public class QuartzServiceImpl implements QuartzService {
@Autowired
private JobEntityRepository repository;
@Override
public JobEntity getById(int id) {
return repository.getById(id);
}
//通过Id获取Job
public JobEntity getJobEntityById(Integer id) {
return repository.getById(id);
}
//从数据库中加载获取到所有Job
public List<JobEntity> loadJobs() {
List<JobEntity> list = new ArrayList<>();
repository.findAll().forEach(list::add);
return list;
}
//获取JobDataMap.(Job参数对象)
public JobDataMap getJobDataMap(JobEntity job) {
JobDataMap map = new JobDataMap();
map.put("name", job.getName());
map.put("group", job.getGroup());
map.put("cronExpression", job.getCron());
map.put("parameter", job.getParameter());
map.put("JobDescription", job.getDescription());
map.put("vmParam", job.getVmParam());
map.put("jarPath", job.getJarPath());
map.put("status", job.getStatus());
return map;
}
//获取JobDetail,JobDetail是任务的定义,而Job是任务的执行逻辑,JobDetail里会引用一个Job Class来定义
public JobDetail geJobDetail(JobKey jobKey, String description, JobDataMap map) {
return JobBuilder.newJob(DynamicJob.class)
.withIdentity(jobKey)
.withDescription(description)
.setJobData(map)
.storeDurably()
.build();
}
//获取Trigger (Job的触发器,执行规则)
public Trigger getTrigger(JobEntity job) {
return TriggerBuilder.newTrigger()
.withIdentity(job.getName(), job.getGroup())
.withSchedule(CronScheduleBuilder.cronSchedule(job.getCron()))
.build();
}
//获取JobKey,包含Name和Group
public JobKey getJobKey(JobEntity job) {
return JobKey.jobKey(job.getName(), job.getGroup());
}
}/**
* :@DisallowConcurrentExecution : 此标记用在实现Job的类上面,意思是不允许并发执行.
* :注意org.quartz.threadPool.threadCount线程池中线程的数量至少要多个,否则@DisallowConcurrentExecution不生效
* :假如Job的设置时间间隔为3秒,但Job执行时间是5秒,设置@DisallowConcurrentExecution以后程序会等任务执行完毕以后再去执行,否则会在3秒时再启用新的线程执行
*/
@DisallowConcurrentExecution
@PersistJobDataAfterExecution //没有异常就更新数据 可用?
@Component
@Slf4j
public class DynamicJob implements Job {
private Logger logger = LoggerFactory.getLogger(DynamicJob.class);
/**
* 核心方法,Quartz Job真正的执行逻辑.
* executorContext JobExecutionContext中封装有Quartz运行所需要的所有信息
* @throws JobExecutionException execute()方法只允许抛出JobExecutionException异常
*/
@Override
public void execute(JobExecutionContext executionContext) throws JobExecutionException {
JobDataMap map = executionContext.getMergedJobDataMap();
String jarPath = map.getString("jarPath");
String parameter = map.getString("parameter");
String vmParam = map.getString("vmParam");
logger.info("Running Job name : {} ", map.getString("name"));
logger.info("Running Job description : " + map.getString("JobDescription"));
logger.info("Running Job group: {} ", map.getString("group"));
logger.info("Running Job cron : " + map.getString("cronExpression"));
logger.info("Running Job jar path : {} ", jarPath);
logger.info("Running Job parameter : {} ", parameter);
logger.info("Running Job vmParam : {} ", vmParam);
long startTime = System.currentTimeMillis();
if (!StringUtils.getStringUtil.isEmpty(jarPath)) {
File jar = new File(jarPath);
if (jar.exists()) {
ProcessBuilder processBuilder = new ProcessBuilder();
processBuilder.directory(jar.getParentFile());
/**
* 这个是java的执行命令
* java -jar
*/
List<String> commands = new ArrayList<>();
commands.add("java");
if (!StringUtils.getStringUtil.isEmpty(vmParam)) {
commands.add(vmParam);
}
commands.add("-jar");
commands.add(jarPath);
commands.add(" &");
System.out.println("commands->\n"+commands);
if (!StringUtils.getStringUtil.isEmpty(parameter)) {
commands.add(parameter);
processBuilder.command(commands);
logger.info("Running Job details as follows >>>>>>>>>>>>>>>>>>>>: ");
logger.info("Running Job commands : {} ", StringUtils.getStringUtil.getListString(commands));
try {
Process process = processBuilder.start();
logProcess(process.getInputStream(), process.getErrorStream());
} catch (Exception e) {
e.printStackTrace();
}
} else {
throw new JobExecutionException("Job Jar not found >> " + jarPath);
}
long endTime = System.currentTimeMillis();
logger.info(">>>>>>>>>>>>> Running Job has been completed , cost time : " + (endTime - startTime) + "ms\n");
}
}
}
//打印Job执行内容的日志
private void logProcess(InputStream inputStream, InputStream errorStream) throws IOException {
String inputLine;
String errorLine;
BufferedReader inputReader = new BufferedReader(new InputStreamReader(inputStream));
BufferedReader errorReader = new BufferedReader(new InputStreamReader(errorStream));
while ((inputLine = inputReader.readLine()) != null){
logger.info(inputLine);
}
while ((errorLine = errorReader.readLine()) != null) {
logger.error(errorLine);
}
}
}