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一、概述
介紹: 流程在執行過程中會產生不同的任務。
- ServiceTask異步任務會產生異步任務,存放在一般工作表act_ru_job中。
- 定時任務會產生定時的任務,在定時時間未到達之前會存放在定時工作表act_ru_timer_job中。
- 掛起任務,比如將未到時間的定時任務手動暫停,則會存放在掛起任務表act_ru_suspended_job中。
- 不可執行任務,如果任務執行失敗,並且在重試次數用完的情況下也沒有成功執行,則任務會存放到不可執行任務表act_ru_deadletter_job中。
二、異步任務
- 設計流程
配置ServiceTask<process id="myProcess_1" isClosed="false" isExecutable="true" processType="None"> <startEvent id="_2" name="StartEvent"/> <endEvent id="_3" name="EndEvent"/> <userTask activiti:exclusive="true" id="UserTask" name="UserTask"/> <!--開啓異步,並指定委託類(在下面編碼中)。注意:activiti開頭的元素不屬於bpmn規範,因此該bpmn文件不能移植到其他流程引擎中--> <serviceTask activiti:exclusive="true" id="ServiceTask" name="ServiceTask" activiti:async="true" activiti:class="com.xjf.test.MyJavaDelegate"/> <sequenceFlow id="_6" sourceRef="_2" targetRef="ServiceTask"/> <sequenceFlow id="_7" sourceRef="ServiceTask" targetRef="UserTask"/> <sequenceFlow id="_8" sourceRef="UserTask" targetRef="_3"/> </process>
- 編碼
委託類:/** * 實現委託類,需要被ServiceTask元素引用 * * @Author: xjf * @Date: 2019/12/2 23:20 */ public class MyJavaDelegate implements JavaDelegate { @Override public void execute(DelegateExecution delegateExecution) { System.out.println("這是處理類"); } }
- 配置:需要在activiti.cfg.xml配置文件中開啓異步執行器
<!--開啓異步執行器,異步纔會自動異步執行,比如異步工作、定時器工作等--> <property name="asyncExecutorActivate" value="true" />
- 發佈
public static void main(String[] args) throws InterruptedException { ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine(); RepositoryService repositoryService = processEngine.getRepositoryService(); RuntimeService runtimeService = processEngine.getRuntimeService(); Deployment deployment = repositoryService.createDeployment().addClasspathResource("service-task.bpmn").deploy(); ProcessDefinition processDefinition = repositoryService.createProcessDefinitionQuery().deploymentId(deployment.getId()).singleResult(); ProcessInstance processInstance = runtimeService.startProcessInstanceById(processDefinition.getId()); // 可以查看act_ru_job,會有異步工作。不過此時沒有開啓異步執行器,流程是卡在ServiceTask任務的,沒有往下執行。 // 開啓後將看不到數據,因爲直接執行了(是異步的) System.out.println("流程實例id: " + processInstance.getId()); processEngine.close(); System.exit(0); }
- 根據控制檯打印的流程實例ID(關閉異步執行器),查看一般工作數據庫:act_ru_job
三、定時任務
- 介紹: 定時任務測試,任務在定時期間會產生定時job,存儲在表 act_ru_timer_job 中。
定時時間到了之後將會被刪除,同時需要配置中開啓異步執行器纔會自動執行
遇到問題: 定時任務到時間後,沒有繼續執行,需要確定
已解決: 程序不能關閉,不然定時時間到了,任務執行不了 - 設計流程
bpmn如下:
xml配置如下:<process id="myProcess_1" isClosed="false" isExecutable="true" processType="None"> <startEvent id="_2" name="StartEvent"/> <intermediateCatchEvent id="IntermediateCatchingEvent" name="IntermediateCatchingEvent"> <timerEventDefinition> <!--定時任務,定時爲一分鐘--> <timeDuration>PT1M</timeDuration> </timerEventDefinition> </intermediateCatchEvent> <userTask activiti:exclusive="true" id="UserTask" name="UserTask"/> <endEvent id="_5" name="EndEvent"/> <sequenceFlow id="_6" sourceRef="_2" targetRef="IntermediateCatchingEvent"/> <sequenceFlow id="_7" sourceRef="IntermediateCatchingEvent" targetRef="UserTask"/> <sequenceFlow id="_8" sourceRef="UserTask" targetRef="_5"/> </process>
- 發佈定時任務(記得打開異步執行器)
ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine(); RepositoryService repositoryService = processEngine.getRepositoryService(); RuntimeService runtimeService = processEngine.getRuntimeService(); Deployment deployment = repositoryService.createDeployment().addClasspathResource("timer-task.bpmn").deploy(); ProcessDefinition processDefinition = repositoryService.createProcessDefinitionQuery().deploymentId(deployment.getId()).singleResult(); ProcessInstance processInstance = runtimeService.startProcessInstanceById(processDefinition.getId()); System.out.println("流程實例id:" + processInstance.getId()); //程序不能馬上關閉,需要等待定時任務執行,然後程序死了,定時任務沒法執行 Thread.sleep(120000); processEngine.close(); System.exit(0);
- 查看數據庫
四、掛起(暫停)任務
- 設計流程:與上面的定時任務一樣,只是把定時時間改爲5分鐘(留有時間操作)。
<timerEventDefinition> <!--定時5分鐘--> <timeDuration>PT5M</timeDuration> </timerEventDefinition>
- 發佈
ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine(); RepositoryService repositoryService = processEngine.getRepositoryService(); RuntimeService runtimeService = processEngine.getRuntimeService(); Deployment deployment = repositoryService.createDeployment().addClasspathResource("suspend-task.bpmn").deploy(); ProcessDefinition processDefinition = repositoryService.createProcessDefinitionQuery().deploymentId(deployment.getId()).singleResult(); ProcessInstance processInstance = runtimeService.startProcessInstanceById(processDefinition.getId()); System.out.println("流程實例ID:" + processInstance.getId()); //因爲定時任務時間爲5分鐘,此時等待10s時工作存放在act_ru_timer_job中 Thread.sleep(10000); //將任務暫停,則任務會存放到表act_ru_suspended_job中 runtimeService.suspendProcessInstanceById(processInstance.getId()); //再次等待10s後,將任務激活,則任務回到act_ru_timer_job中 Thread.sleep(10000); runtimeService.activateProcessInstanceById(processInstance.getId()); processEngine.close(); System.exit(0);
- 在對應的時間裏去查看act_ru_suspended_job和act_ru_timer_job,可以看到任務的轉變
五、不可執行任務
- 設計流程:流程和上面的異步任務一樣,不過委託類換一個如下。我們需要手動報錯
public class ExceptionDelegate implements JavaDelegate { @Override public void execute(DelegateExecution execution) { System.out.println("這是執行器"); //測試不可執行的任務,手動出錯 throw new RuntimeException("always exception 手動拋出"); } }
- 編碼發佈(記得打開異步執行器)
ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine(); RepositoryService repositoryService = processEngine.getRepositoryService(); RuntimeService runtimeService = processEngine.getRuntimeService(); ManagementService managementService = processEngine.getManagementService(); Deployment deployment = repositoryService.createDeployment().addClasspathResource("error-task.bpmn").deploy(); ProcessDefinition processDefinition = repositoryService.createProcessDefinitionQuery().deploymentId(deployment.getId()).singleResult(); ProcessInstance processInstance = runtimeService.startProcessInstanceById(processDefinition.getId()); System.out.println("流程實例ID:" + processInstance.getId()); //任務重試次數默認爲三次,手動設置爲一次,方便快速測試查看 Job job = managementService.createJobQuery().processInstanceId(processInstance.getId()).singleResult(); managementService.setJobRetries(job.getId(),1); Thread.sleep(30000); processEngine.close(); System.exit(0);
- 查看不可執行的任務數據庫表:act_ru_deadletter_job