xxl-job（v2.1.0 Release）调度器端任务启动执行的原理
（一）xxl-job介绍以及搭建过程
（二）xxl-job执行器端的执行器自动注册原理
（三）xxl-job调度器端的执行器自动注册原理
（四）xxl-job任务管理以及调度器端任务手动执行的原理
（五）xxl-job调度器端任务启动执行的原理
（六）xxl-job执行器端接收调度器任务执行的原理
进入任务管理页面，点击启动任务（不是执行一次），这个过程又是如何的呢，我们来看看。
1、先研究调度中心的配置方法类XxlJobScheduler
public class JobScheduleHelper {
public void start(){
// 开启ringThread线程在此线程中有个while循环
ringThread = new Thread(new Runnable() {
@Override
public void run() {
while (!ringThreadToStop) {
try {
// ring trigger
if (ringItemData!=null && ringItemData.size()>0) {
// do trigger
for (int jobId: ringItemData) {
//通过 JobTriggerPoolHelper触发任务
JobTriggerPoolHelper.trigger(jobId, TriggerTypeEnum.CRON, -1, null, null);
}
// clear
ringItemData.clear();
}
} catch (Exception e) {
if (!ringThreadToStop) {
logger.error(">>>>>>>>>>> xxl-job, JobScheduleHelper#ringThread error:{}", e);
}
}
}
});
ringThread.setDaemon(true);
ringThread.setName("xxl-job, admin JobScheduleHelper#ringThread");
ringThread.start();
}
启动执行任务是通过JobTriggerPoolHelper.trigger()处理的，继续跟踪代码
public static void trigger(int jobId, TriggerTypeEnum triggerType, int failRetryCount, String executorShardingParam, String executorParam) {
helper.addTrigger(jobId, triggerType, failRetryCount, executorShardingParam, executorParam);
}
public static void trigger(int jobId, TriggerTypeEnum triggerType, int failRetryCount, String executorShardingParam, String executorParam) {
// 加载数据
XxlJobInfo jobInfo = XxlJobAdminConfig.getAdminConfig().getXxlJobInfoDao().loadById(jobId);
if (executorParam != null) {
//设置执行器的配置参数
jobInfo.setExecutorParam(executorParam);
}
//设置失败重试次数
int finalFailRetryCount = failRetryCount>=0?failRetryCount:jobInfo.getExecutorFailRetryCount();
//根据执行器主键id 从xxl_job_group表中获取执行器的app_name和执行器address_list(地址:端口号)
XxlJobGroup group = XxlJobAdminConfig.getAdminConfig().getXxlJobGroupDao().load(jobInfo.getJobGroup());
//执行器路由策略
// 分片广播策略，广播触发对应集群中所有机器执行一次任务，同时系统自动传递分片参数；可根据分片参数开发分片任务；
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 {
//其他路由策略
if (shardingParam == null) {
shardingParam = new int[]{0, 1};
}
processTrigger(group, jobInfo, finalFailRetryCount, triggerType, shardingParam[0], shardingParam[1]);
}
}
继续关注processTrigger()
private static void processTrigger(XxlJobGroup group, XxlJobInfo jobInfo, int finalFailRetryCount, TriggerTypeEnum triggerType, int index, int total){
// 获取参数 阻塞策略
ExecutorBlockStrategyEnum blockStrategy = ExecutorBlockStrategyEnum.match(jobInfo.getExecutorBlockStrategy(), ExecutorBlockStrategyEnum.SERIAL_EXECUTION);
// 获取参数 路由策略
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、存储日志
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、初始化 trigger参数
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.setLogDateTim(jobLog.getTriggerTime().getTime());
triggerParam.setGlueType(jobInfo.getGlueType());
triggerParam.setGlueSource(jobInfo.getGlueSource());
triggerParam.setGlueUpdatetime(jobInfo.getGlueUpdatetime().getTime());
triggerParam.setBroadcastIndex(index);
triggerParam.setBroadcastTotal(total);
// 3、初始化 执行器的地址
String address = null;
ReturnT routeAddressResult = null;
//group.getRegistryList() 获取执行器的地址
if (group.getRegistryList()!=null && !group.getRegistryList().isEmpty()) {
//如果路由策略是分片广播 就获取getRegistryList对应的执行器地址
if (ExecutorRouteStrategyEnum.SHARDING_BROADCAST == executorRouteStrategyEnum) {
if (index < group.getRegistryList().size()) {
address = group.getRegistryList().get(index);
} else {
address = group.getRegistryList().get(0);
}
} else {
//如果路由策略是其他策略
//根据不同路由策略，通过ExecutorRouter的实现类的route()获取执行器地址
routeAddressResult = executorRouteStrategyEnum.getRouter().route(triggerParam, group.getRegistryList());
if (routeAddressResult.getCode() == ReturnT.SUCCESS_CODE) {
address = routeAddressResult.getContent();
}
}
} else {
routeAddressResult = new ReturnT(ReturnT.FAIL_CODE, I18nUtil.getString("jobconf_trigger_address_empty"));
}
// 4、trigger remote executor
ReturnT triggerResult = null;
if (address != null) {
//根据address地址，远程调用执行器服务接口，执行任务
triggerResult = runExecutor(triggerParam, address);
} else {
triggerResult = new ReturnT(ReturnT.FAIL_CODE, null);
}
继续跟踪runExecutor()
public static ReturnT runExecutor(TriggerParam triggerParam, String address){
ReturnT runResult = null;
try {
//获取执行器动态代理类
ExecutorBiz executorBiz = XxlJobScheduler.getExecutorBiz(address);
//执行run的时候，动态代理就会执行InvocationHandler对象的invoke()
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(ReturnT.FAIL_CODE, ThrowableUtil.toString(e));
}
StringBuffer runResultSB = new StringBuffer(I18nUtil.getString("jobconf_trigger_run") + "：");
runResultSB.append("
address：").append(address);
runResultSB.append("
code：").append(runResult.getCode());
runResultSB.append("
msg：").append(runResult.getMsg());
runResult.setMsg(runResultSB.toString());
return runResult;
}
通过 XxlJobScheduler.getExecutorBiz(address)获取执行器代理类
public static ExecutorBiz getExecutorBiz(String address) throws Exception {
// set-cache
executorBiz = (ExecutorBiz) new XxlRpcReferenceBean(
NetEnum.NETTY_HTTP,
Serializer.SerializeEnum.HESSIAN.getSerializer(),
CallType.SYNC,
LoadBalance.ROUND,
ExecutorBiz.class,
null,
3000,
address,
XxlJobAdminConfig.getAdminConfig().getAccessToken(),
null,
null).getObject();
return executorBiz;
}
同样我们关注一下getObject()方法
public Object getObject() {
return Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(), new Class[]{this.iface}, new InvocationHandler() {
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
//获取执行器实现类的类名
String className = method.getDeclaringClass().getName();
String varsion_ = XxlRpcReferenceBean.this.version;
//获取方法名
String methodName = method.getName();
Class[] parameterTypes = method.getParameterTypes();
..........................................................
if (finalAddress != null && finalAddress.trim().length() != 0) {
// request封装
XxlRpcRequest xxlRpcRequest = new XxlRpcRequest();
xxlRpcRequest.setRequestId(UUID.randomUUID().toString());
xxlRpcRequest.setCreateMillisTime(System.currentTimeMillis());
xxlRpcRequest.setAccessToken(XxlRpcReferenceBean.this.accessToken);
xxlRpcRequest.setClassName(className);
xxlRpcRequest.setMethodName(methodName);
xxlRpcRequest.setParameterTypes(parameterTypes);
xxlRpcRequest.setParameters(parameters);
XxlRpcFutureResponse futureResponse;
if (CallType.SYNC == XxlRpcReferenceBean.this.callType) {
futureResponse = new XxlRpcFutureResponse(XxlRpcReferenceBean.this.invokerFactory, xxlRpcRequest, (XxlRpcInvokeCallback)null);
Object var31;
try {
// 通过nettyClient.send发送请求执行的方法名和参数
XxlRpcReferenceBean.this.client.asyncSend(finalAddress, xxlRpcRequest);
XxlRpcResponse xxlRpcResponse = futureResponse.get(XxlRpcReferenceBean.this.timeout, TimeUnit.MILLISECONDS);
if (xxlRpcResponse.getErrorMsg() != null) {
throw new XxlRpcException(xxlRpcResponse.getErrorMsg());
}
//执行器动态代理ExecutorBiz
var31 = xxlRpcResponse.getResult();
} catch (Exception var21) {
XxlRpcReferenceBean.logger.info(">>>>>>>>>>> xxl-rpc, invoke error, address:{}, XxlRpcRequest{}", finalAddress, xxlRpcRequest);
throw (Throwable)(var21 instanceof XxlRpcException ? var21 : new XxlRpcException(var21));
} finally {
futureResponse.removeInvokerFuture();
}
//var31就是执行器 动态代理ExecutorBiz
return var31;
}
到了这里我们就生成了执行器的动态代理ExecutorBiz，那么反过来在研究一下executorBiz.run(triggerParam)，这段代码的执行实际上是通过InvocationHandler对象的invoke()方法去执行的，在invoke方法中通过nettyClient向执行器发送了需要执行的方法名和参数，那么执行器通过RPC收到请求后就开始执行任务。