flowable学习笔记(四)：动态多实例

1.定义流程模板

【测试用户任务多实例】任务节点配置了以下属性：
集合(多实例)：userList。这个创建流程实例时入参需要加上这个参数。
元素变量(多实例)：user。工作流创建多实例时会将集合(多实例)的值拆分成元素变量(多实例)，这个例子每个实例会有一个入参变量名称是user。
多实例类型：我设置成Parallel(并行)。
完成条件(多实例)：${nrOfCompletedInstances/nrOfInstances == 1} 表示全部实例通过提交才算完成。${nrOfCompletedInstances/nrOfInstances >= 0.5} 表示一半的实例通过提交才算完成。
nrOfCompletedInstances：完成实例数。number of Completed Instances
nrOfInstances：总实例数。number of Instances
执行监听器：配置一个执行监听器CommonMoreInstancesExecutionListener，用于打印流程变量。
任务监听器：配置一个任务监听器CommonMoreInstancesTaskListener，用于打印流程变量。

结束节点配置了以下属性：
执行监听器：配置一个执行监听器CommonEndExecutionListener，用于判断任务节点结束条件。

2.代码

(1)CommonMoreInstancesExecutionListener

package gdut.listener;import org.flowable.engine.delegate.DelegateExecution;
import org.flowable.engine.delegate.ExecutionListener;
import org.springframework.stereotype.Component;import java.util.Map;
import java.util.Random;@Component
public class CommonMoreInstancesExecutionListener implements ExecutionListener {@Overridepublic void notify(DelegateExecution delegateExecution) {System.out.println("CommonMoreInstancesExecutionListener start");Map<String, Object> variables = delegateExecution.getVariables();System.out.println("CommonMoreInstancesExecutionListener variables is:" + variables);System.out.println("CommonMoreInstancesExecutionListener executionId is:" + delegateExecution.getId());}
}

(2)CommonMoreInstancesTaskListener

package gdut.listener;import org.flowable.engine.delegate.TaskListener;
import org.flowable.task.service.delegate.DelegateTask;
import org.springframework.stereotype.Component;import java.util.Map;@Component
public class CommonMoreInstancesTaskListener implements TaskListener {@Overridepublic void notify(DelegateTask delegateTask) {System.out.println("CommonMoreInstancesTaskListener start");Map<String, Object> variables = delegateTask.getVariables();System.out.println("CommonMoreInstancesTaskListener variables is:" + variables);System.out.println("CommonMoreInstancesTaskListener executionId is:" + delegateTask.getExecutionId());System.out.println("CommonMoreInstancesTaskListener taskId is:" + delegateTask.getId());}
}

(3)创建流程实例接口

//创建流程实例@PostMapping("/createFlowInstanceByMap")public String createFlowInstanceByMap(@RequestBody JSONObject params) {String flowDefinitionName = params.getStr("flowDefinitionName");Map<String, Object> paramsMap = BeanUtil.beanToMap(params);ProcessInstance processInstance = runtimeService.startProcessInstanceByKey(flowDefinitionName, paramsMap);System.out.println("createFlowInstanceByMap instanceId is:" + processInstance.getProcessInstanceId());return processInstance.getProcessInstanceId();}

3.测试

部署流程定义：
http://localhost:8081/flowable/deployFlowDefinition?fileName=TestMoreInstances.bpmn20.xml

创建流程实例：
http://localhost:8081/flowable/createFlowInstanceByMap
{
“flowDefinitionName”:“TestMoreInstances”,
“userList”:[“liufeifei”, “liushanshan”, “liuhao”]
}

打印输出：

CommonStartExecutionListener start
CommonStartExecutionListener variables is:{userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances}
CommonMoreInstancesExecutionListener start
CommonMoreInstancesExecutionListener variables is:{userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener}
CommonMoreInstancesExecutionListener executionId is:caa751e3-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesExecutionListener start
CommonMoreInstancesExecutionListener variables is:{nrOfActiveInstances=3, userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener, loopCounter=0, user=liufeifei, nrOfInstances=3, nrOfCompletedInstances=0}
CommonMoreInstancesExecutionListener executionId is:caaaad4b-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesTaskListener start
CommonMoreInstancesTaskListener variables is:{nrOfActiveInstances=3, userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener, loopCounter=0, user=liufeifei, nrOfInstances=3, nrOfCompletedInstances=0}
CommonMoreInstancesTaskListener executionId is:caaaad4b-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesTaskListener taskId is:caab4993-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesExecutionListener start
CommonMoreInstancesExecutionListener variables is:{nrOfActiveInstances=3, userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener, loopCounter=1, user=liushanshan, nrOfInstances=3, nrOfCompletedInstances=0}
CommonMoreInstancesExecutionListener executionId is:caaaad4c-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesTaskListener start
CommonMoreInstancesTaskListener variables is:{nrOfActiveInstances=3, userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener, loopCounter=1, user=liushanshan, nrOfInstances=3, nrOfCompletedInstances=0}
CommonMoreInstancesTaskListener executionId is:caaaad4c-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesTaskListener taskId is:caae7de6-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesExecutionListener start
CommonMoreInstancesExecutionListener variables is:{nrOfActiveInstances=3, userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener, loopCounter=2, user=liuhao, nrOfInstances=3, nrOfCompletedInstances=0}
CommonMoreInstancesExecutionListener executionId is:caaaad4d-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesTaskListener start
CommonMoreInstancesTaskListener variables is:{nrOfActiveInstances=3, userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener, loopCounter=2, user=liuhao, nrOfInstances=3, nrOfCompletedInstances=0}
CommonMoreInstancesTaskListener executionId is:caaaad4d-875b-11ed-a341-c03c5949a6ca
CommonMoreInstancesTaskListener taskId is:cab02b99-875b-11ed-a341-c03c5949a6ca
createFlowInstanceByMap instanceId is:caa5a42e-875b-11ed-a341-c03c5949a6ca

总结：
(1)从上面的打印输出可以发现：flowable是先调用了一次执行监听器，再创建了3个用户任务实例(我请求的参数userList数组长度是3)。
(2)创建的多实例的执行监听器和任务监听器获取到的流程参数，除了创建流程实例的入参，还增加了以下几个变量：
nrOfActiveInstances 活跃的实例数
loopCounter 类似for循环下标 for(int i = 0;i < userList.size();i++) 表示i的值。
nrOfInstances 总的实例数
nrOfCompletedInstances 完成实例数
user 元素变量获取userList.get(i)的值。
(3)查看flowable数据库表ACT_RU_TASK有三条记录：
select * from ACT_RU_TASK where PROC_INST_ID_ = ‘caa5a42e-875b-11ed-a341-c03c5949a6ca’;

提交任务
http://localhost:8081/flowable/completeTaskId?taskId=caab4993-875b-11ed-a341-c03c5949a6ca
完成一个任务，结束节点监听器没有执行。ACT_RU_TASK表还有2条记录。

http://localhost:8081/flowable/completeTaskId?taskId=caae7de6-875b-11ed-a341-c03c5949a6ca
完成第二个任务，结束节点监听器没有执行。ACT_RU_TASK表还有1条记录。

http://localhost:8081/flowable/completeTaskId?taskId=cab02b99-875b-11ed-a341-c03c5949a6ca
提交第三个任务，结束节点监听器执行了，ACT_RU_TASK表没有记录。

结束节点执行监听器打印输出：

CommonEndExecutionListener end
CommonEndExecutionListener variables is:{userList=["liufeifei","liushanshan","liuhao"], flowDefinitionName=TestMoreInstances, commonStartExecutionListener=CommonStartExecutionListener}

符合我配置的完成条件，3个实例全部完成，该任务节点才算通过。

bpmn.xml

(1)TestMoreInstances.bpmn20.xml

<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:flowable="http://flowable.org/bpmn" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:omgdc="http://www.omg.org/spec/DD/20100524/DC" xmlns:omgdi="http://www.omg.org/spec/DD/20100524/DI" typeLanguage="http://www.w3.org/2001/XMLSchema" expressionLanguage="http://www.w3.org/1999/XPath" targetNamespace="http://www.flowable.org/processdef" exporter="Flowable Open Source Modeler" exporterVersion="6.7.2"><process id="TestMoreInstances" name="TestMoreInstances" isExecutable="true"><documentation>测试多实例</documentation><startEvent id="testMoreInstancesStart" name="测试用户任务多实例开始节点" flowable:formFieldValidation="true"><extensionElements><flowable:executionListener event="start" delegateExpression="${commonStartExecutionListener}"></flowable:executionListener></extensionElements></startEvent><userTask id="TestMoreUserTaskInstances" name="测试用户任务多实例" flowable:formFieldValidation="true"><extensionElements><flowable:executionListener event="start" delegateExpression="${commonMoreInstancesExecutionListener}"></flowable:executionListener><flowable:taskListener event="create" delegateExpression="${commonMoreInstancesTaskListener}"></flowable:taskListener></extensionElements><multiInstanceLoopCharacteristics isSequential="false" flowable:collection="userList" flowable:elementVariable="user"><extensionElements></extensionElements><completionCondition>${nrOfCompletedInstances/nrOfInstances == 1}</completionCondition></multiInstanceLoopCharacteristics></userTask><endEvent id="testMoreInstancesEnd" name="测试用户任务多实例结束节点"><extensionElements><flowable:executionListener event="start" delegateExpression="${commonEndExecutionListener}"></flowable:executionListener></extensionElements></endEvent><sequenceFlow id="sid-FF142143-F573-4FD7-905A-BBA5E118F13F" sourceRef="testMoreInstancesStart" targetRef="TestMoreUserTaskInstances"></sequenceFlow><sequenceFlow id="sid-90EEDCBB-5375-4A8E-A1C3-C239743F9D96" sourceRef="TestMoreUserTaskInstances" targetRef="testMoreInstancesEnd"></sequenceFlow></process><bpmndi:BPMNDiagram id="BPMNDiagram_TestMoreInstances"><bpmndi:BPMNPlane bpmnElement="TestMoreInstances" id="BPMNPlane_TestMoreInstances"><bpmndi:BPMNShape bpmnElement="testMoreInstancesStart" id="BPMNShape_testMoreInstancesStart"><omgdc:Bounds height="30.0" width="30.0" x="135.0" y="70.0"></omgdc:Bounds></bpmndi:BPMNShape><bpmndi:BPMNShape bpmnElement="TestMoreUserTaskInstances" id="BPMNShape_TestMoreUserTaskInstances"><omgdc:Bounds height="80.0" width="100.0" x="285.0" y="45.0"></omgdc:Bounds></bpmndi:BPMNShape><bpmndi:BPMNShape bpmnElement="testMoreInstancesEnd" id="BPMNShape_testMoreInstancesEnd"><omgdc:Bounds height="28.0" width="28.0" x="510.0" y="71.0"></omgdc:Bounds></bpmndi:BPMNShape><bpmndi:BPMNEdge bpmnElement="sid-FF142143-F573-4FD7-905A-BBA5E118F13F" id="BPMNEdge_sid-FF142143-F573-4FD7-905A-BBA5E118F13F" flowable:sourceDockerX="15.0" flowable:sourceDockerY="15.0" flowable:targetDockerX="50.0" flowable:targetDockerY="40.0"><omgdi:waypoint x="164.94999946593478" y="85.0"></omgdi:waypoint><omgdi:waypoint x="285.0" y="85.0"></omgdi:waypoint></bpmndi:BPMNEdge><bpmndi:BPMNEdge bpmnElement="sid-90EEDCBB-5375-4A8E-A1C3-C239743F9D96" id="BPMNEdge_sid-90EEDCBB-5375-4A8E-A1C3-C239743F9D96" flowable:sourceDockerX="50.0" flowable:sourceDockerY="40.0" flowable:targetDockerX="14.0" flowable:targetDockerY="14.0"><omgdi:waypoint x="384.94999999998174" y="85.0"></omgdi:waypoint><omgdi:waypoint x="510.0" y="85.0"></omgdi:waypoint></bpmndi:BPMNEdge></bpmndi:BPMNPlane></bpmndi:BPMNDiagram>
</definitions>

参考

flowable 报错 Waiting for changelog lock…
flowable多实例任务注意事项
Flowable—多实例任务：会签