「这是我参与2022首次更文挑战的第30天，活动详情查看：2022首次更文挑战」。
xxl-job 在当下是一个炙手可热的分布式任务调度框架，在分布式系统中我们常常通过xxl-job做定时任务，它简单易用，天然支持分布式场景，多种路由策略可选，支持弹性扩缩容...本篇文章我们就从源码层面分析一下xxl-job-admin(调度中心)。
1 xxl-job 简介
XXL-JOB是一个分布式任务调度平台，其核心设计目标是开发迅速、学习简单、轻量级、易扩展。
其源码分为三部分：
- xxl-job-admin 调度中心
- xxl-job-core 核心依赖
- xxl-job-executor-samples 示例
2 xxl-job-admin（调度中心）核心源码分析
本篇文章我们先来分析一下xxl-job-admin的源码，xxl-job-admin是一个独立的项目，我们需要将其单独部署在服务器上，支持集群模式。xxl-job-admin负责管理调度信息，按照调度配置发出调度请求，自身不承担业务代码。调度系统与任务解耦，提高了系统可用性和稳定性，同时调度系统性能不再受限于任务模块；支持可视化、简单且动态的管理调度信息，包括任务新建，更新，删除，GLUE开发和任务报警等，所有上述操作都会实时生效，同时支持监控调度结果以及执行日志，支持执行器故障转移（Failover）。
调度中心就是根据配置的任务信息，在合适的时间调用执行器执行任务，目的就是将任务和调度解耦。
2.1 调度器启动
它的启动方式也是基于Spring，是在属性填充后执行，首先是获取配置，然后就是初始化调度器。
@Component
public class XxlJobAdminConfig implements InitializingBean, DisposableBean {
private static XxlJobAdminConfig adminConfig = null;
public static XxlJobAdminConfig getAdminConfig() {
return adminConfig;
}
// ---------------------- XxlJobScheduler ----------------------
private XxlJobScheduler xxlJobScheduler;
@Override
public void afterPropertiesSet() throws Exception {
adminConfig = this;
xxlJobScheduler = new XxlJobScheduler();
xxlJobScheduler.init();
}
@Override
public void destroy() throws Exception {
xxlJobScheduler.destroy();
}
// ---------------------- XxlJobScheduler ----------------------
// conf
@Value("${xxl.job.i18n}")
private String i18n;
@Value("${xxl.job.accessToken}")
private String accessToken;
@Value("${spring.mail.from}")
private String emailFrom;
@Value("${xxl.job.triggerpool.fast.max}")
private int triggerPoolFastMax;
@Value("${xxl.job.triggerpool.slow.max}")
private int triggerPoolSlowMax;
@Value("${xxl.job.logretentiondays}")
private int logretentiondays;
@Resource
private XxlJobLogDao xxlJobLogDao;
@Resource
private XxlJobInfoDao xxlJobInfoDao;
@Resource
private XxlJobRegistryDao xxlJobRegistryDao;
@Resource
private XxlJobGroupDao xxlJobGroupDao;
@Resource
private XxlJobLogReportDao xxlJobLogReportDao;
@Resource
private JavaMailSender mailSender;
@Resource
private DataSource dataSource;
@Resource
private JobAlarmer jobAlarmer;
public String getI18n() {
if (!Arrays.asList("zh_CN", "zh_TC", "en").contains(i18n)) {
return "zh_CN";
}
return i18n;
}
// 省略get() set()方法
...
}
2.2 xxlJobScheduler 初始化
这里我们只看最为核心的代码
初始化步骤：
- 国际化
- 触发器线程池
- 注册监视器（任务服务心跳监控）
- 文件监控器
- 任务完成（丢失任务监控器）
- 日志报告监控
- 任务调度
public void init() throws Exception {
// init i18n
initI18n();
// admin trigger pool start
JobTriggerPoolHelper.toStart();
// admin registry monitor run
JobRegistryHelper.getInstance().start();
// admin fail-monitor run
JobFailMonitorHelper.getInstance().start();
// admin lose-monitor run ( depend on JobTriggerPoolHelper )
JobCompleteHelper.getInstance().start();
// admin log report start
JobLogReportHelper.getInstance().start();
// start-schedule ( depend on JobTriggerPoolHelper )
JobScheduleHelper.getInstance().start();
logger.info(">>>>>>>>> init xxl-job admin success.");
}
2.3 JobTriggerPoolHelper触发器线程池
JobTriggerPoolHelper是其中最为核心的一个类，它通过线程池的方式能够实现多任务并行触发执行，我们调度中心向执行器发号施令都是通过此处，这里一快一慢构建了两个线程池。当任务的超时时间设置超过10秒时，我们认为其为慢任务，使用慢触发器线程池去处理，没有设置超时间和超时时间小于10s的我们认为其运行很快交由快触发器线程池处理。
这里addTrigger是核心方法，使我们触发任务时调用的。
public class JobTriggerPoolHelper {
private static Logger logger = LoggerFactory.getLogger(JobTriggerPoolHelper.class);
// ---------------------- trigger pool ----------------------
private ThreadPoolExecutor fastTriggerPool = null;
private ThreadPoolExecutor slowTriggerPool = null;
public void start(){
fastTriggerPool = new ThreadPoolExecutor(
10,
XxlJobAdminConfig.getAdminConfig().getTriggerPoolFastMax(),
60L,
TimeUnit.SECONDS,
new LinkedBlockingQueue<Runnable>(1000),
new ThreadFactory() {
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "xxl-job, admin JobTriggerPoolHelper-fastTriggerPool-" + r.hashCode());
}
});
slowTriggerPool = new ThreadPoolExecutor(
10,
XxlJobAdminConfig.getAdminConfig().getTriggerPoolSlowMax(),
60L,
TimeUnit.SECONDS,
new LinkedBlockingQueue<Runnable>(2000),
new ThreadFactory() {
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "xxl-job, admin JobTriggerPoolHelper-slowTriggerPool-" + r.hashCode());
}
});
}
public void stop() {
//triggerPool.shutdown();
fastTriggerPool.shutdownNow();
slowTriggerPool.shutdownNow();
logger.info(">>>>>>>>> xxl-job trigger thread pool shutdown success.");
}
// job timeout count
private volatile long minTim = System.currentTimeMillis()/60000; // ms > min
private volatile ConcurrentMap<Integer, AtomicInteger> jobTimeoutCountMap = new ConcurrentHashMap<>();
public void addTrigger(final int jobId,
final TriggerTypeEnum triggerType,
final int failRetryCount,
final String executorShardingParam,
final String executorParam,
final String addressList) {
// choose thread pool
ThreadPoolExecutor triggerPool_ = fastTriggerPool;
AtomicInteger jobTimeoutCount = jobTimeoutCountMap.get(jobId);
if (jobTimeoutCount!=null && jobTimeoutCount.get() > 10) { // job-timeout 10 times in 1 min
triggerPool_ = slowTriggerPool;
}
// trigger
triggerPool_.execute(new Runnable() {
@Override
public void run() {
long start = System.currentTimeMillis();
try {
// do trigger
XxlJobTrigger.trigger(jobId, triggerType, failRetryCount, executorShardingParam, executorParam, addressList);
} catch (Exception e) {
logger.error(e.getMessage(), e);
} finally {
// check timeout-count-map
long minTim_now = System.currentTimeMillis()/60000;
if (minTim != minTim_now) {
minTim = minTim_now;
jobTimeoutCountMap.clear();
}
// incr timeout-count-map
long cost = System.currentTimeMillis()-start;
if (cost > 500) {
AtomicInteger timeoutCount = jobTimeoutCountMap.putIfAbsent(jobId, new AtomicInteger(1));
if (timeoutCount != null) {
timeoutCount.incrementAndGet();
}
}
}
}
});
}
// ---------------------- helper ----------------------
private static JobTriggerPoolHelper helper = new JobTriggerPoolHelper();
public static void toStart() {
helper.start();
}
public static void toStop() {
helper.stop();
}
public static void trigger(int jobId, TriggerTypeEnum triggerType, int failRetryCount, String executorShardingParam, String executorParam, String addressList) {
helper.addTrigger(jobId, triggerType, failRetryCount, executorShardingParam, executorParam, addressList);
}
}
2.4 XxlJobTrigger 任务触发器
该类是任务触发的详细流程
- trigger
- 获取任务详细信息
- 设置任务参数
- 获取失败重试次数
- 获取任务组（执行机器）
- 判断是否需要分片广播（此处可将分片参数传入，每台机器执行对应的分片任务）
- processTrigger
- 获取阻塞策略
- 获取路由策略
- 获取分片参数
- 记录日志log-id
- 初始化触发器参数
- 初始化调用地址
- runExecutor
- rpc远程调用executorBiz.run(triggerParam)（触发执行器执行任务）
- 获取调用结果
- 记录日志trigger-info
public class XxlJobTrigger {
private static Logger logger = LoggerFactory.getLogger(XxlJobTrigger.class);
public static void trigger(int jobId,
TriggerTypeEnum triggerType,
int failRetryCount,
String executorShardingParam,
String executorParam,
String addressList) {
// load data
XxlJobInfo jobInfo = XxlJobAdminConfig.getAdminConfig().getXxlJobInfoDao().loadById(jobId);
if (jobInfo == null) {
logger.warn(">>>>>>>>>>>> trigger fail, jobId invalid，jobId={}", jobId);
return;
}
if (executorParam != null) {
jobInfo.setExecutorParam(executorParam);
}
int finalFailRetryCount = failRetryCount>=0?failRetryCount:jobInfo.getExecutorFailRetryCount();
XxlJobGroup group = XxlJobAdminConfig.getAdminConfig().getXxlJobGroupDao().load(jobInfo.getJobGroup());
// cover addressList
if (addressList!=null && addressList.trim().length()>0) {
group.setAddressType(1);
group.setAddressList(addressList.trim());
}
// sharding param
int[] shardingParam = null;
if (executorShardingParam!=null){
String[] shardingArr = executorShardingParam.split("/");
if (shardingArr.length==2 && isNumeric(shardingArr[0]) && isNumeric(shardingArr[1])) {
shardingParam = new int[2];
shardingParam[0] = Integer.valueOf(shardingArr[0]);
shardingParam[1] = Integer.valueOf(shardingArr[1]);
}
}
if (ExecutorRouteStrategyEnum.SHARDING_BROADCAST==ExecutorRouteStrategyEnum.match(jobInfo.getExecutorRouteStrategy(), null)
&& group.getRegistryList()!=null && !group.getRegistryList().isEmpty()
&& shardingParam==null) {
for (int i = 0; i < group.getRegistryList().size(); i++) {
processTrigger(group, jobInfo, finalFailRetryCount, triggerType, i, group.getRegistryList().size());
}
} else {
if (shardingParam == null) {
shardingParam = new int[]{0, 1};
}
processTrigger(group, jobInfo, finalFailRetryCount, triggerType, shardingParam[0], shardingParam[1]);
}
}
private static boolean isNumeric(String str){
try {
int result = Integer.valueOf(str);
return true;
} catch (NumberFormatException e) {
return false;
}
}
private static void processTrigger(XxlJobGroup group, XxlJobInfo jobInfo, int finalFailRetryCount, TriggerTypeEnum triggerType, int index, int total){
// param
ExecutorBlockStrategyEnum blockStrategy = ExecutorBlockStrategyEnum.match(jobInfo.getExecutorBlockStrategy(), ExecutorBlockStrategyEnum.SERIAL_EXECUTION); // block strategy
ExecutorRouteStrategyEnum executorRouteStrategyEnum = ExecutorRouteStrategyEnum.match(jobInfo.getExecutorRouteStrategy(), null); // route strategy
String shardingParam = (ExecutorRouteStrategyEnum.SHARDING_BROADCAST==executorRouteStrategyEnum)?String.valueOf(index).concat("/").concat(String.valueOf(total)):null;
// 1、save log-id
XxlJobLog jobLog = new XxlJobLog();
jobLog.setJobGroup(jobInfo.getJobGroup());
jobLog.setJobId(jobInfo.getId());
jobLog.setTriggerTime(new Date());
XxlJobAdminConfig.getAdminConfig().getXxlJobLogDao().save(jobLog);
logger.debug(">>>>>>>>>>> xxl-job trigger start, jobId:{}", jobLog.getId());
// 2、init trigger-param
TriggerParam triggerParam = new TriggerParam();
triggerParam.setJobId(jobInfo.getId());
triggerParam.setExecutorHandler(jobInfo.getExecutorHandler());
triggerParam.setExecutorParams(jobInfo.getExecutorParam());
triggerParam.setExecutorBlockStrategy(jobInfo.getExecutorBlockStrategy());
triggerParam.setExecutorTimeout(jobInfo.getExecutorTimeout());
triggerParam.setLogId(jobLog.getId());
triggerParam.setLogDateTime(jobLog.getTriggerTime().getTime());
triggerParam.setGlueType(jobInfo.getGlueType());
triggerParam.setGlueSource(jobInfo.getGlueSource());
triggerParam.setGlueUpdatetime(jobInfo.getGlueUpdatetime().getTime());
triggerParam.setBroadcastIndex(index);
triggerParam.setBroadcastTotal(total);
// 3、init address
String address = null;
ReturnT<String> routeAddressResult = null;
if (group.getRegistryList()!=null && !group.getRegistryList().isEmpty()) {
if (ExecutorRouteStrategyEnum.SHARDING_BROADCAST == executorRouteStrategyEnum) {
if (index < group.getRegistryList().size()) {
address = group.getRegistryList().get(index);
} else {
address = group.getRegistryList().get(0);
}
} else {
routeAddressResult = executorRouteStrategyEnum.getRouter().route(triggerParam, group.getRegistryList());
if (routeAddressResult.getCode() == ReturnT.SUCCESS_CODE) {
address = routeAddressResult.getContent();
}
}
} else {
routeAddressResult = new ReturnT<String>(ReturnT.FAIL_CODE, I18nUtil.getString("jobconf_trigger_address_empty"));
}
// 4、trigger remote executor
ReturnT<String> triggerResult = null;
if (address != null) {
triggerResult = runExecutor(triggerParam, address);
} else {
triggerResult = new ReturnT<String>(ReturnT.FAIL_CODE, null);
}
// 5、collection trigger info
StringBuffer triggerMsgSb = new StringBuffer();
triggerMsgSb.append(I18nUtil.getString("jobconf_trigger_type")).append("：").append(triggerType.getTitle());
triggerMsgSb.append("<br>").append(I18nUtil.getString("jobconf_trigger_admin_adress")).append("：").append(IpUtil.getIp());
triggerMsgSb.append("<br>").append(I18nUtil.getString("jobconf_trigger_exe_regtype")).append("：")
.append( (group.getAddressType() == 0)?I18nUtil.getString("jobgroup_field_addressType_0"):I18nUtil.getString("jobgroup_field_addressType_1") );
triggerMsgSb.append("<br>").append(I18nUtil.getString("jobconf_trigger_exe_regaddress")).append("：").append(group.getRegistryList());
triggerMsgSb.append("<br>").append(I18nUtil.getString("jobinfo_field_executorRouteStrategy")).append("：").append(executorRouteStrategyEnum.getTitle());
if (shardingParam != null) {
triggerMsgSb.append("("+shardingParam+")");
}
triggerMsgSb.append("<br>").append(I18nUtil.getString("jobinfo_field_executorBlockStrategy")).append("：").append(blockStrategy.getTitle());
triggerMsgSb.append("<br>").append(I18nUtil.getString("jobinfo_field_timeout")).append("：").append(jobInfo.getExecutorTimeout());
triggerMsgSb.append("<br>").append(I18nUtil.getString("jobinfo_field_executorFailRetryCount")).append("：").append(finalFailRetryCount);
triggerMsgSb.append("<br><br><span style=\"color:#00c0ef;\" > >>>>>>>>>>>"+ I18nUtil.getString("jobconf_trigger_run") +"<<<<<<<<<<< </span><br>")
.append((routeAddressResult!=null&&routeAddressResult.getMsg()!=null)?routeAddressResult.getMsg()+"<br><br>":"").append(triggerResult.getMsg()!=null?triggerResult.getMsg():"");
// 6、save log trigger-info
jobLog.setExecutorAddress(address);
jobLog.setExecutorHandler(jobInfo.getExecutorHandler());
jobLog.setExecutorParam(jobInfo.getExecutorParam());
jobLog.setExecutorShardingParam(shardingParam);
jobLog.setExecutorFailRetryCount(finalFailRetryCount);
//jobLog.setTriggerTime();
jobLog.setTriggerCode(triggerResult.getCode());
jobLog.setTriggerMsg(triggerMsgSb.toString());
XxlJobAdminConfig.getAdminConfig().getXxlJobLogDao().updateTriggerInfo(jobLog);
logger.debug(">>>>>>>>>>> xxl-job trigger end, jobId:{}", jobLog.getId());
}
public static ReturnT<String> runExecutor(TriggerParam triggerParam, String address){
ReturnT<String> runResult = null;
try {
ExecutorBiz executorBiz = XxlJobScheduler.getExecutorBiz(address);
runResult = executorBiz.run(triggerParam);
} catch (Exception e) {
logger.error(">>>>>>>>>>> xxl-job trigger error, please check if the executor[{}] is running.", address, e);
runResult = new ReturnT<String>(ReturnT.FAIL_CODE, ThrowableUtil.toString(e));
}
StringBuffer runResultSB = new StringBuffer(I18nUtil.getString("jobconf_trigger_run") + "：");
runResultSB.append("<br>address：").append(address);
runResultSB.append("<br>code：").append(runResult.getCode());
runResultSB.append("<br>msg：").append(runResult.getMsg());
runResult.setMsg(runResultSB.toString());
return runResult;
}
}
2.5 JobRegistryHelper 心跳检测线程池
这里会有一个线程实时检测每个任务组的注册情况，每当有服务注册会启动单独的线程进行注册。
public class JobRegistryHelper {
private static Logger logger = LoggerFactory.getLogger(JobRegistryHelper.class);
private static JobRegistryHelper instance = new JobRegistryHelper();
public static JobRegistryHelper getInstance(){
return instance;
}
private ThreadPoolExecutor registryOrRemoveThreadPool = null;
private Thread registryMonitorThread;
private volatile boolean toStop = false;
public void start(){
// for registry or remove
registryOrRemoveThreadPool = new ThreadPoolExecutor(
2,
10,
30L,
TimeUnit.SECONDS,
new LinkedBlockingQueue<Runnable>(2000),
new ThreadFactory() {
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "xxl-job, admin JobRegistryMonitorHelper-registryOrRemoveThreadPool-" + r.hashCode());
}
},
new RejectedExecutionHandler() {
@Override
public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {
r.run();
logger.warn(">>>>>>>>>>> xxl-job, registry or remove too fast, match threadpool rejected handler(run now).");
}
});
// for monitor
registryMonitorThread = new Thread(new Runnable() {
@Override
public void run() {
while (!toStop) {
try {
// auto registry group
List<XxlJobGroup> groupList = XxlJobAdminConfig.getAdminConfig().getXxlJobGroupDao().findByAddressType(0);
if (groupList!=null && !groupList.isEmpty()) {
// remove dead address (admin/executor)
List<Integer> ids = XxlJobAdminConfig.getAdminConfig().getXxlJobRegistryDao().findDead(RegistryConfig.DEAD_TIMEOUT, new Date());
if (ids!=null && ids.size()>0) {
XxlJobAdminConfig.getAdminConfig().getXxlJobRegistryDao().removeDead(ids);
}
// fresh online address (admin/executor)
HashMap<String, List<String>> appAddressMap = new HashMap<String, List<String>>();
List<XxlJobRegistry> list = XxlJobAdminConfig.getAdminConfig().getXxlJobRegistryDao().findAll(RegistryConfig.DEAD_TIMEOUT, new Date());
if (list != null) {
for (XxlJobRegistry item: list) {
if (RegistryConfig.RegistType.EXECUTOR.name().equals(item.getRegistryGroup())) {
String appname = item.getRegistryKey();
List<String> registryList = appAddressMap.get(appname);
if (registryList == null) {
registryList = new ArrayList<String>();
}
if (!registryList.contains(item.getRegistryValue())) {
registryList.add(item.getRegistryValue());
}
appAddressMap.put(appname, registryList);
}
}
}
// fresh group address
for (XxlJobGroup group: groupList) {
List<String> registryList = appAddressMap.get(group.getAppname());
String addressListStr = null;
if (registryList!=null && !registryList.isEmpty()) {
Collections.sort(registryList);
StringBuilder addressListSB = new StringBuilder();
for (String item:registryList) {
addressListSB.append(item).append(",");
}
addressListStr = addressListSB.toString();
addressListStr = addressListStr.substring(0, addressListStr.length()-1);
}
group.setAddressList(addressListStr);
group.setUpdateTime(new Date());
XxlJobAdminConfig.getAdminConfig().getXxlJobGroupDao().update(group);
}
}
} catch (Exception e) {
if (!toStop) {
logger.error(">>>>>>>>>>> xxl-job, job registry monitor thread error:{}", e);
}
}
try {
TimeUnit.SECONDS.sleep(RegistryConfig.BEAT_TIMEOUT);
} catch (InterruptedException e) {
if (!toStop) {
logger.error(">>>>>>>>>>> xxl-job, job registry monitor thread error:{}", e);
}
}
}
logger.info(">>>>>>>>>>> xxl-job, job registry monitor thread stop");
}
});
registryMonitorThread.setDaemon(true);
registryMonitorThread.setName("xxl-job, admin JobRegistryMonitorHelper-registryMonitorThread");
registryMonitorThread.start();
}
public void toStop(){
toStop = true;
// stop registryOrRemoveThreadPool
registryOrRemoveThreadPool.shutdownNow();
// stop monitir (interrupt and wait)
registryMonitorThread.interrupt();
try {
registryMonitorThread.join();
} catch (InterruptedException e) {
logger.error(e.getMessage(), e);
}
}
// ---------------------- helper ----------------------
public ReturnT<String> registry(RegistryParam registryParam) {
// valid
if (!StringUtils.hasText(registryParam.getRegistryGroup())
|| !StringUtils.hasText(registryParam.getRegistryKey())
|| !StringUtils.hasText(registryParam.getRegistryValue())) {
return new ReturnT<String>(ReturnT.FAIL_CODE, "Illegal Argument.");
}
// async execute
registryOrRemoveThreadPool.execute(new Runnable() {
@Override
public void run() {
int ret = XxlJobAdminConfig.getAdminConfig().getXxlJobRegistryDao().registryUpdate(registryParam.getRegistryGroup(), registryParam.getRegistryKey(), registryParam.getRegistryValue(), new Date());
if (ret < 1) {
XxlJobAdminConfig.getAdminConfig().getXxlJobRegistryDao().registrySave(registryParam.getRegistryGroup(), registryParam.getRegistryKey(), registryParam.getRegistryValue(), new Date());
// fresh
freshGroupRegistryInfo(registryParam);
}
}
});
return ReturnT.SUCCESS;
}
public ReturnT<String> registryRemove(RegistryParam registryParam) {
// valid
if (!StringUtils.hasText(registryParam.getRegistryGroup())
|| !StringUtils.hasText(registryParam.getRegistryKey())
|| !StringUtils.hasText(registryParam.getRegistryValue())) {
return new ReturnT<String>(ReturnT.FAIL_CODE, "Illegal Argument.");
}
// async execute
registryOrRemoveThreadPool.execute(new Runnable() {
@Override
public void run() {
int ret = XxlJobAdminConfig.getAdminConfig().getXxlJobRegistryDao().registryDelete(registryParam.getRegistryGroup(), registryParam.getRegistryKey(), registryParam.getRegistryValue());
if (ret > 0) {
// fresh
freshGroupRegistryInfo(registryParam);
}
}
});
return ReturnT.SUCCESS;
}
private void freshGroupRegistryInfo(RegistryParam registryParam){
// Under consideration, prevent affecting core tables
}
}
2.6 JobScheduleHelper 任务调度线程
调度线程scheduleThread
- 开启事务
- 根据时刻获取任务列表
- 当任务满足条件会调用触发器触发任务执行
- 当前时间> 触发时间 + 预读时间
- 调度过期策略判断是否需要再次执行
- 当前时间> 触发时间
- 触发任务
- 刷新下一次触发时间
- 当前时间小于等于触发时间
- 加入时间环中，等待执行
- 刷新下一次触发时间
- 当前时间> 触发时间 + 预读时间
- 修改保存调度结果
- 提交事务
ringThread 将上述线程推入待触发的任务，根据时刻触发执行
public class JobScheduleHelper {
private static Logger logger = LoggerFactory.getLogger(JobScheduleHelper.class);
private static JobScheduleHelper instance = new JobScheduleHelper();
public static JobScheduleHelper getInstance(){
return instance;
}
public static final long PRE_READ_MS = 5000; // pre read
private Thread scheduleThread;
private Thread ringThread;
private volatile boolean scheduleThreadToStop = false;
private volatile boolean ringThreadToStop = false;
private volatile static Map<Integer, List<Integer>> ringData = new ConcurrentHashMap<>();
public void start(){
// schedule thread
scheduleThread = new Thread(new Runnable() {
@Override
public void run() {
try {
TimeUnit.MILLISECONDS.sleep(5000 - System.currentTimeMillis()%1000 );
} catch (InterruptedException e) {
if (!scheduleThreadToStop) {
logger.error(e.getMessage(), e);
}
}
logger.info(">>>>>>>>> init xxl-job admin scheduler success.");
// pre-read count: treadpool-size * trigger-qps (each trigger cost 50ms, qps = 1000/50 = 20)
int preReadCount = (XxlJobAdminConfig.getAdminConfig().getTriggerPoolFastMax() + XxlJobAdminConfig.getAdminConfig().getTriggerPoolSlowMax()) * 20;
while (!scheduleThreadToStop) {
// Scan Job
long start = System.currentTimeMillis();
Connection conn = null;
Boolean connAutoCommit = null;
PreparedStatement preparedStatement = null;
boolean preReadSuc = true;
try {
conn = XxlJobAdminConfig.getAdminConfig().getDataSource().getConnection();
connAutoCommit = conn.getAutoCommit();
conn.setAutoCommit(false);
preparedStatement = conn.prepareStatement( "select * from xxl_job_lock where lock_name = 'schedule_lock' for update" );
preparedStatement.execute();
// tx start
// 1、pre read
long nowTime = System.currentTimeMillis();
List<XxlJobInfo> scheduleList = XxlJobAdminConfig.getAdminConfig().getXxlJobInfoDao().scheduleJobQuery(nowTime + PRE_READ_MS, preReadCount);
if (scheduleList!=null && scheduleList.size()>0) {
// 2、push time-ring
for (XxlJobInfo jobInfo: scheduleList) {
// time-ring jump
if (nowTime > jobInfo.getTriggerNextTime() + PRE_READ_MS) {
// 2.1、trigger-expire > 5s：pass && make next-trigger-time
logger.warn(">>>>>>>>>>> xxl-job, schedule misfire, jobId = " + jobInfo.getId());
// 1、misfire match
MisfireStrategyEnum misfireStrategyEnum = MisfireStrategyEnum.match(jobInfo.getMisfireStrategy(), MisfireStrategyEnum.DO_NOTHING);
if (MisfireStrategyEnum.FIRE_ONCE_NOW == misfireStrategyEnum) {
// FIRE_ONCE_NOW 》 trigger
JobTriggerPoolHelper.trigger(jobInfo.getId(), TriggerTypeEnum.MISFIRE, -1, null, null, null);
logger.debug(">>>>>>>>>>> xxl-job, schedule push trigger : jobId = " + jobInfo.getId() );
}
// 2、fresh next
refreshNextValidTime(jobInfo, new Date());
} else if (nowTime > jobInfo.getTriggerNextTime()) {
// 2.2、trigger-expire < 5s：direct-trigger && make next-trigger-time
// 1、trigger
JobTriggerPoolHelper.trigger(jobInfo.getId(), TriggerTypeEnum.CRON, -1, null, null, null);
logger.debug(">>>>>>>>>>> xxl-job, schedule push trigger : jobId = " + jobInfo.getId() );
// 2、fresh next
refreshNextValidTime(jobInfo, new Date());
// next-trigger-time in 5s, pre-read again
if (jobInfo.getTriggerStatus()==1 && nowTime + PRE_READ_MS > jobInfo.getTriggerNextTime()) {
// 1、make ring second
int ringSecond = (int)((jobInfo.getTriggerNextTime()/1000)%60);
// 2、push time ring
pushTimeRing(ringSecond, jobInfo.getId());
// 3、fresh next
refreshNextValidTime(jobInfo, new Date(jobInfo.getTriggerNextTime()));
}
} else {
// 2.3、trigger-pre-read：time-ring trigger && make next-trigger-time
// 1、make ring second
int ringSecond = (int)((jobInfo.getTriggerNextTime()/1000)%60);
// 2、push time ring
pushTimeRing(ringSecond, jobInfo.getId());
// 3、fresh next
refreshNextValidTime(jobInfo, new Date(jobInfo.getTriggerNextTime()));
}
}
// 3、update trigger info
for (XxlJobInfo jobInfo: scheduleList) {
XxlJobAdminConfig.getAdminConfig().getXxlJobInfoDao().scheduleUpdate(jobInfo);
}
} else {
preReadSuc = false;
}
// tx stop
} catch (Exception e) {
if (!scheduleThreadToStop) {
logger.error(">>>>>>>>>>> xxl-job, JobScheduleHelper#scheduleThread error:{}", e);
}
} finally {
// commit
if (conn != null) {
try {
conn.commit();
} catch (SQLException e) {
if (!scheduleThreadToStop) {
logger.error(e.getMessage(), e);
}
}
try {
conn.setAutoCommit(connAutoCommit);
} catch (SQLException e) {
if (!scheduleThreadToStop) {
logger.error(e.getMessage(), e);
}
}
try {
conn.close();
} catch (SQLException e) {
if (!scheduleThreadToStop) {
logger.error(e.getMessage(), e);
}
}
}
// close PreparedStatement
if (null != preparedStatement) {
try {
preparedStatement.close();
} catch (SQLException e) {
if (!scheduleThreadToStop) {
logger.error(e.getMessage(), e);
}
}
}
}
long cost = System.currentTimeMillis()-start;
// Wait seconds, align second
if (cost < 1000) { // scan-overtime, not wait
try {
// pre-read period: success > scan each second; fail > skip this period;
TimeUnit.MILLISECONDS.sleep((preReadSuc?1000:PRE_READ_MS) - System.currentTimeMillis()%1000);
} catch (InterruptedException e) {
if (!scheduleThreadToStop) {
logger.error(e.getMessage(), e);
}
}
}
}
logger.info(">>>>>>>>>>> xxl-job, JobScheduleHelper#scheduleThread stop");
}
});
scheduleThread.setDaemon(true);
scheduleThread.setName("xxl-job, admin JobScheduleHelper#scheduleThread");
scheduleThread.start();
// ring thread
ringThread = new Thread(new Runnable() {
@Override
public void run() {
while (!ringThreadToStop) {
// align second
try {
TimeUnit.MILLISECONDS.sleep(1000 - System.currentTimeMillis() % 1000);
} catch (InterruptedException e) {
if (!ringThreadToStop) {
logger.error(e.getMessage(), e);
}
}
try {
// second data
List<Integer> ringItemData = new ArrayList<>();
int nowSecond = Calendar.getInstance().get(Calendar.SECOND); // 避免处理耗时太长，跨过刻度，向前校验一个刻度；
for (int i = 0; i < 2; i++) {
List<Integer> tmpData = ringData.remove( (nowSecond+60-i)%60 );
if (tmpData != null) {
ringItemData.addAll(tmpData);
}
}
// ring trigger
logger.debug(">>>>>>>>>>> xxl-job, time-ring beat : " + nowSecond + " = " + Arrays.asList(ringItemData) );
if (ringItemData.size() > 0) {
// do trigger
for (int jobId: ringItemData) {
// do trigger
JobTriggerPoolHelper.trigger(jobId, TriggerTypeEnum.CRON, -1, null, null, null);
}
// clear
ringItemData.clear();
}
} catch (Exception e) {
if (!ringThreadToStop) {
logger.error(">>>>>>>>>>> xxl-job, JobScheduleHelper#ringThread error:{}", e);
}
}
}
logger.info(">>>>>>>>>>> xxl-job, JobScheduleHelper#ringThread stop");
}
});
ringThread.setDaemon(true);
ringThread.setName("xxl-job, admin JobScheduleHelper#ringThread");
ringThread.start();
}
private void refreshNextValidTime(XxlJobInfo jobInfo, Date fromTime) throws Exception {
Date nextValidTime = generateNextValidTime(jobInfo, fromTime);
if (nextValidTime != null) {
jobInfo.setTriggerLastTime(jobInfo.getTriggerNextTime());
jobInfo.setTriggerNextTime(nextValidTime.getTime());
} else {
jobInfo.setTriggerStatus(0);
jobInfo.setTriggerLastTime(0);
jobInfo.setTriggerNextTime(0);
logger.warn(">>>>>>>>>>> xxl-job, refreshNextValidTime fail for job: jobId={}, scheduleType={}, scheduleConf={}",
jobInfo.getId(), jobInfo.getScheduleType(), jobInfo.getScheduleConf());
}
}
private void pushTimeRing(int ringSecond, int jobId){
// push async ring
List<Integer> ringItemData = ringData.get(ringSecond);
if (ringItemData == null) {
ringItemData = new ArrayList<Integer>();
ringData.put(ringSecond, ringItemData);
}
ringItemData.add(jobId);
logger.debug(">>>>>>>>>>> xxl-job, schedule push time-ring : " + ringSecond + " = " + Arrays.asList(ringItemData) );
}
public void toStop(){
// 1、stop schedule
scheduleThreadToStop = true;
try {
TimeUnit.SECONDS.sleep(1); // wait
} catch (InterruptedException e) {
logger.error(e.getMessage(), e);
}
if (scheduleThread.getState() != Thread.State.TERMINATED){
// interrupt and wait
scheduleThread.interrupt();
try {
scheduleThread.join();
} catch (InterruptedException e) {
logger.error(e.getMessage(), e);
}
}
// if has ring data
boolean hasRingData = false;
if (!ringData.isEmpty()) {
for (int second : ringData.keySet()) {
List<Integer> tmpData = ringData.get(second);
if (tmpData!=null && tmpData.size()>0) {
hasRingData = true;
break;
}
}
}
if (hasRingData) {
try {
TimeUnit.SECONDS.sleep(8);
} catch (InterruptedException e) {
logger.error(e.getMessage(), e);
}
}
// stop ring (wait job-in-memory stop)
ringThreadToStop = true;
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
logger.error(e.getMessage(), e);
}
if (ringThread.getState() != Thread.State.TERMINATED){
// interrupt and wait
ringThread.interrupt();
try {
ringThread.join();
} catch (InterruptedException e) {
logger.error(e.getMessage(), e);
}
}
logger.info(">>>>>>>>>>> xxl-job, JobScheduleHelper stop");
}
// ---------------------- tools ----------------------
public static Date generateNextValidTime(XxlJobInfo jobInfo, Date fromTime) throws Exception {
ScheduleTypeEnum scheduleTypeEnum = ScheduleTypeEnum.match(jobInfo.getScheduleType(), null);
if (ScheduleTypeEnum.CRON == scheduleTypeEnum) {
Date nextValidTime = new CronExpression(jobInfo.getScheduleConf()).getNextValidTimeAfter(fromTime);
return nextValidTime;
} else if (ScheduleTypeEnum.FIX_RATE == scheduleTypeEnum /*|| ScheduleTypeEnum.FIX_DELAY == scheduleTypeEnum*/) {
return new Date(fromTime.getTime() + Integer.valueOf(jobInfo.getScheduleConf())*1000 );
}
return null;
}
}
3 总结
调度中心是分布式任务调度的重中之中，我们下面再来过一下其执行流程
- Spring初始化
- 调度器初始化
- 国际化
- 触发器线程池
- 注册监视器（任务服务心跳监控）
- 文件监控器
- 任务完成（丢失任务监控器）
- 日志报告监控
- 任务调度
- 任务调度线程，监控到待执行任务
- 调度通过触发器线程池执行调度
- 调度判断其是不是分片任务
- 根据路由策略，阻塞处理策略触发rpc远程调用执行器执行任务
- 执行器触发执行，任务结束后写回响应结果
