Activiti无指定开始事件实例

Activiti无指定开始事件指不为开始事件指定任何的触发条件的事件。下面将通过一个实例来学习什么是无指定开始事件。

（无指定开始事件图标）

流程图：

流程启动后进入“任务01”（调用complete方法来完成该任务），然后结束流程。

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流程定义XML：

<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="https://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" xmlns:activiti="https://activiti.org/bpmn" xmlns:bpmndi="https://www.omg.org/spec/BPMN/20100524/DI" xmlns:omgdc="https://www.omg.org/spec/DD/20100524/DC" xmlns:omgdi="https://www.omg.org/spec/DD/20100524/DI" typeLanguage="https://www.w3.org/2001/XMLSchema" expressionLanguage="https://www.w3.org/1999/XPath" targetNamespace="https://www.activiti.org/processdef">
  <process id="startEventTest01" name="开始事件测试01" isExecutable="true">
    <startEvent id="start"></startEvent>
    <userTask id="task01" name="任务01"></userTask>
    <endEvent id="end"></endEvent>
    <sequenceFlow id="sid-B96A1813-6837-4845-8167-3ACA1A3B3D20" sourceRef="start" targetRef="task01"></sequenceFlow>
    <sequenceFlow id="sid-35F14E43-5255-4FCC-8962-209578CDE088" sourceRef="task01" targetRef="end"></sequenceFlow>
  </process>
  
  <bpmndi:BPMNDiagram id="BPMNDiagram_startEventTest01">
    <bpmndi:BPMNPlane bpmnElement="startEventTest01" id="BPMNPlane_startEventTest01">
      <bpmndi:BPMNShape bpmnElement="start" id="BPMNShape_start">
        <omgdc:Bounds height="30.0" width="30.0" x="116.0" y="150.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="task01" id="BPMNShape_task01">
        <omgdc:Bounds height="80.0" width="100.0" x="191.0" y="125.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="end" id="BPMNShape_end">
        <omgdc:Bounds height="28.0" width="28.0" x="336.0" y="151.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNEdge bpmnElement="sid-35F14E43-5255-4FCC-8962-209578CDE088" id="BPMNEdge_sid-35F14E43-5255-4FCC-8962-209578CDE088">
        <omgdi:waypoint x="291.0" y="165.0"></omgdi:waypoint>
        <omgdi:waypoint x="336.0" y="165.0"></omgdi:waypoint>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="sid-B96A1813-6837-4845-8167-3ACA1A3B3D20" id="BPMNEdge_sid-B96A1813-6837-4845-8167-3ACA1A3B3D20">
        <omgdi:waypoint x="146.0" y="165.0"></omgdi:waypoint>
        <omgdi:waypoint x="191.0" y="165.0"></omgdi:waypoint>
      </bpmndi:BPMNEdge>
    </bpmndi:BPMNPlane>
  </bpmndi:BPMNDiagram>
</definitions>

客户端测试代码：

package com.bug315.event;

import org.activiti.engine.ProcessEngine;
import org.activiti.engine.ProcessEngines;
import org.activiti.engine.RepositoryService;
import org.activiti.engine.RuntimeService;
import org.activiti.engine.TaskService;
import org.activiti.engine.repository.Deployment;
import org.activiti.engine.runtime.ProcessInstance;
import org.activiti.engine.task.Task;

/**
 * 开始事件测试
 * @author Administrator
 *
 */
public class StartEventTest01 {

	public static void main(String[] args) {
		ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
		RepositoryService repositoryService = processEngine.getRepositoryService();
		Deployment deployment = repositoryService.createDeployment().addClasspathResource("bpmn/startEventTest01.bpmn20.xml").deploy();
		System.out.println("deployment Id = " + deployment.getId());
		System.out.println("deployment Name = " + deployment.getName());
		
		RuntimeService runtimeService = processEngine.getRuntimeService();
		ProcessInstance processInstance = runtimeService.startProcessInstanceByKey("startEventTest01");
		System.out.println("processInstance Id = " + processInstance.getId());
		System.out.println("processInstance BusinessKey = " + processInstance.getBusinessKey());
		
		TaskService taskService = processEngine.getTaskService();
		Task task = taskService.createTaskQuery().singleResult();
		System.out.println("task Id = " + task.getId());
		System.out.println("task Name = " + task.getName());
		taskService.complete(task.getId());
		System.out.println("task完成");
		
		task = taskService.createTaskQuery().singleResult();
		System.out.println("task = " + task);
	}
	
}

Activiti配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="https://www.springframework.org/schema/beans"
	xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="https://www.springframework.org/schema/beans
		https://www.springframework.org/schema/beans/spring-beans-3.1.xsd">
    <bean id="processEngineConfiguration"  
        class="org.activiti.engine.impl.cfg.StandaloneProcessEngineConfiguration">
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/activiti" />
        <property name="jdbcDriver" value="com.mysql.jdbc.Driver" />
        <property name="jdbcUsername" value="root" />
        <property name="jdbcPassword" value="aaaaaa" />
        <property name="jobExecutorActivate" value="true" />
        <property name="databaseType" value="mysql"/>
        <property name="databaseSchemaUpdate" value="true" />
        <property name="history" value="full"/>
    </bean>
</beans>

注意事项：

1、流程引擎并不知道流程将在什么时候开始，如果要启动流程，必须使用startProcessBy***方法。

2、子流程中总会有一个无指定开始事件，即使将开始事件强制定义为其他开始事件，其也会被当作无指定开始事件。因为流程到达子流程时，就意味着子流程需要启动，而且并不需要其他启动条件。