Activiti之 Exclusive Gateway

一、Exclusive Gateway

　　Exclusive Gateway（也称为XOR网关或更多技术基于数据的排他网关）经常用做决定流程的流转方向。当流程到达该网关的时候，所有的流出序列流到按照已定义好的顺序依次执行。当序列流条件的求值结果为true(或没有条件集的时候,在概念上有定义一个“true”定义序列流)，就会选择该序列继续的处理。Exclusive Gateway的图标就是菱形里面有一个X符合，如下所示：

　　

　　XML的代码为：

<exclusiveGateway id="exclusiveGw" name="Exclusive Gateway" />

<sequenceFlow id="flow2" sourceRef="exclusiveGw" targetRef="theTask1">
  <conditionExpression xsi:type="tFormalExpression">${input == 1}</conditionExpression>
</sequenceFlow>

<sequenceFlow id="flow3" sourceRef="exclusiveGw" targetRef="theTask2">
  <conditionExpression xsi:type="tFormalExpression">${input == 2}</conditionExpression>
</sequenceFlow>

<sequenceFlow id="flow4" sourceRef="exclusiveGw" targetRef="theTask3">
  <conditionExpression xsi:type="tFormalExpression">${input == 3}</conditionExpression>
</sequenceFlow>

 二、示例

　　本例子以请假流程为例，流程设计图如下图所示：

　　

　　当员工提出的请假时间大于2天的时候由总经理审批，当请假时间不大于2天的时候由经理审批。

　　1、leave.bpmn内容如下： 

<?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:activiti="http://activiti.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.activiti.org/test">
  <process id="leave" name="请假流程图" isExecutable="true">
    <documentation>请假流程图</documentation>
    <startEvent id="startevent1" name="Start"></startEvent>
    <endEvent id="endevent1" name="End"></endEvent>
    <!-- ${employeeId} 中的employeeId 在启动流程实例的时候，就设置employeeId变量。再根据employeeId获取员工请假任务，最后设置请假时间进行提交-->
    <userTask id="usertask1" name="员工请假" activiti:assignee="${employeeId}"></userTask>
    <userTask id="usertask2" name="经理审批" activiti:candidateGroups="manager"></userTask>
    <userTask id="usertask3" name="总经理审批" activiti:candidateGroups="boss"></userTask>
    <sequenceFlow id="flow1" sourceRef="startevent1" targetRef="usertask1"></sequenceFlow>
    <sequenceFlow id="flow2" name="${flag == true}" sourceRef="usertask2" targetRef="endevent1">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flag == true}]]></conditionExpression>
    </sequenceFlow>
    <sequenceFlow id="flow3" name="${flag == true}" sourceRef="usertask3" targetRef="endevent1">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flag == true}]]></conditionExpression>
    </sequenceFlow>
    <sequenceFlow id="flow4" name="${flag == false}" sourceRef="usertask2" targetRef="usertask1">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flag == false}]]></conditionExpression>
    </sequenceFlow>
    <sequenceFlow id="flow5" name="${flag == false}" sourceRef="usertask3" targetRef="usertask1">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flag == false}]]></conditionExpression>
    </sequenceFlow>
    <exclusiveGateway id="exclusivegateway1" name="Exclusive Gateway"></exclusiveGateway>
    <sequenceFlow id="flow6" sourceRef="usertask1" targetRef="exclusivegateway1"></sequenceFlow>
    <sequenceFlow id="flow7" name="${day &lt;= 2}" sourceRef="exclusivegateway1" targetRef="usertask2">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${day <= 2}]]></conditionExpression>
    </sequenceFlow>
    <sequenceFlow id="flow8" name="${day &gt; 2}" sourceRef="exclusivegateway1" targetRef="usertask3">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${day > 2}]]></conditionExpression>
    </sequenceFlow>
  </process>
  <bpmndi:BPMNDiagram id="BPMNDiagram_leave">
    <bpmndi:BPMNPlane bpmnElement="leave" id="BPMNPlane_leave">
      <bpmndi:BPMNShape bpmnElement="startevent1" id="BPMNShape_startevent1">
        <omgdc:Bounds height="35.0" width="35.0" x="355.0" y="48.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="endevent1" id="BPMNShape_endevent1">
        <omgdc:Bounds height="35.0" width="35.0" x="355.0" y="362.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="usertask1" id="BPMNShape_usertask1">
        <omgdc:Bounds height="55.0" width="105.0" x="320.0" y="112.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="usertask2" id="BPMNShape_usertask2">
        <omgdc:Bounds height="55.0" width="105.0" x="170.0" y="240.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="usertask3" id="BPMNShape_usertask3">
        <omgdc:Bounds height="55.0" width="105.0" x="480.0" y="242.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="exclusivegateway1" id="BPMNShape_exclusivegateway1">
        <omgdc:Bounds height="40.0" width="40.0" x="352.0" y="247.0"></omgdc:Bounds>
      </bpmndi:BPMNShape>
      <bpmndi:BPMNEdge bpmnElement="flow1" id="BPMNEdge_flow1">
        <omgdi:waypoint x="372.0" y="83.0"></omgdi:waypoint>
        <omgdi:waypoint x="372.0" y="112.0"></omgdi:waypoint>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="flow2" id="BPMNEdge_flow2">
        <omgdi:waypoint x="222.0" y="295.0"></omgdi:waypoint>
        <omgdi:waypoint x="222.0" y="379.0"></omgdi:waypoint>
        <omgdi:waypoint x="355.0" y="379.0"></omgdi:waypoint>
        <bpmndi:BPMNLabel>
          <omgdc:Bounds height="14.0" width="100.0" x="183.0" y="309.0"></omgdc:Bounds>
        </bpmndi:BPMNLabel>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="flow3" id="BPMNEdge_flow3">
        <omgdi:waypoint x="532.0" y="297.0"></omgdi:waypoint>
        <omgdi:waypoint x="532.0" y="379.0"></omgdi:waypoint>
        <omgdi:waypoint x="390.0" y="379.0"></omgdi:waypoint>
        <bpmndi:BPMNLabel>
          <omgdc:Bounds height="14.0" width="100.0" x="483.0" y="309.0"></omgdc:Bounds>
        </bpmndi:BPMNLabel>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="flow4" id="BPMNEdge_flow4">
        <omgdi:waypoint x="222.0" y="240.0"></omgdi:waypoint>
        <omgdi:waypoint x="222.0" y="139.0"></omgdi:waypoint>
        <omgdi:waypoint x="320.0" y="139.0"></omgdi:waypoint>
        <bpmndi:BPMNLabel>
          <omgdc:Bounds height="14.0" width="100.0" x="170.0" y="191.0"></omgdc:Bounds>
        </bpmndi:BPMNLabel>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="flow5" id="BPMNEdge_flow5">
        <omgdi:waypoint x="532.0" y="242.0"></omgdi:waypoint>
        <omgdi:waypoint x="532.0" y="139.0"></omgdi:waypoint>
        <omgdi:waypoint x="425.0" y="139.0"></omgdi:waypoint>
        <bpmndi:BPMNLabel>
          <omgdc:Bounds height="14.0" width="100.0" x="485.0" y="191.0"></omgdc:Bounds>
        </bpmndi:BPMNLabel>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="flow6" id="BPMNEdge_flow6">
        <omgdi:waypoint x="372.0" y="167.0"></omgdi:waypoint>
        <omgdi:waypoint x="372.0" y="247.0"></omgdi:waypoint>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="flow7" id="BPMNEdge_flow7">
        <omgdi:waypoint x="352.0" y="267.0"></omgdi:waypoint>
        <omgdi:waypoint x="275.0" y="267.0"></omgdi:waypoint>
        <bpmndi:BPMNLabel>
          <omgdc:Bounds height="14.0" width="100.0" x="283.0" y="247.0"></omgdc:Bounds>
        </bpmndi:BPMNLabel>
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="flow8" id="BPMNEdge_flow8">
        <omgdi:waypoint x="392.0" y="267.0"></omgdi:waypoint>
        <omgdi:waypoint x="480.0" y="269.0"></omgdi:waypoint>
        <bpmndi:BPMNLabel>
          <omgdc:Bounds height="14.0" width="100.0" x="400.0" y="247.0"></omgdc:Bounds>
        </bpmndi:BPMNLabel>
      </bpmndi:BPMNEdge>
    </bpmndi:BPMNPlane>
  </bpmndi:BPMNDiagram>
</definitions>

　　2、测试类LeaveTest代码如下：

package com.shh.test;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.activiti.engine.HistoryService;
import org.activiti.engine.ProcessEngine;
import org.activiti.engine.ProcessEngineConfiguration;
import org.activiti.engine.RepositoryService;
import org.activiti.engine.RuntimeService;
import org.activiti.engine.TaskService;
import org.activiti.engine.history.HistoricProcessInstanceQuery;
import org.activiti.engine.task.Task;
import org.junit.Before;
import org.junit.Test;
/**
 * 请假流程
 */
public class LeaveTest {
    ProcessEngine processEngine = null;
    RepositoryService repositoryService = null;
    RuntimeService runtimeService = null;
    TaskService taskService = null; 

    /**
     * 加载配置文件
     */
    @Before
    public void init() {
        processEngine = ProcessEngineConfiguration.createProcessEngineConfigurationFromResource("activiti.cfg.xml")
                .buildProcessEngine();
        repositoryService = processEngine.getRepositoryService();
        runtimeService = processEngine.getRuntimeService();
        taskService = processEngine.getTaskService();
    }

    /**
     * 部署流程定义
     */
    @Test
    public void deploy(){
        repositoryService.createDeployment().addClasspathResource("diagrams/leave.bpmn").deploy();
        System.out.println("***************部署流程定义完成***************");
    }
    
    /**
     * 启动一个请假流程
     */
    @Test
    public void start() {
        Map<String, Object> variables = new HashMap<String, Object>();
        variables.put("employeeId", "Kermit"); //请假人
        String processId = runtimeService.startProcessInstanceByKey("leave", variables).getId();
        System.out.println("***************启动一个请假流程完成***************" + processId);
    }

    /**
     * 提交请假申请
     */
    @Test
    public void apply(){
        System.out.println("***************提交请假申请开始***************");
        List<Task> tasks = taskService.createTaskQuery().taskAssignee("Kermit").list();
        System.out.println(tasks.size());
        for (Task task : tasks) {
            System.out.println("Kermit的任务taskname:" + task.getName() + ",id:" + task.getId());
            taskService.setVariable(task.getId(), "day", 4);//设置请假天数
            taskService.complete(task.getId());//完成任务  
            System.out.println("请假4 天");
        }
        System.out.println("***************提交请假申请完成***************");
    }
    
    @Test
    public void step2manager() {
        System.out.println("***************经理组审批流程开始***************");
        List<Task> tasks = taskService.createTaskQuery().taskCandidateGroup("manager").list();// 经理组的任务
        System.out.println("经理组的任务：" + tasks.size());
        for (Task task : tasks) {
            System.out.println("经理组的任务taskname:" + task.getName() + ",id:" + task.getId());
            taskService.claim(task.getId(), "李四");//申领任务 
            taskService.setVariable(task.getId(), "flag", false);//true批准，false不批准
            Object applyUser = taskService.getVariable(task.getId(), "employeeId");
            Object day = taskService.getVariable(task.getId(), "day");
            System.out.println(String.format("%s请假%s天", applyUser, day));
            taskService.complete(task.getId());//完成任务 
        }
        System.out.println("***************经理组审批流程结束***************");
    }
    
    @Test
    public void step2Boss() {
        System.out.println("***************总经理组审批流程开始***************");
        List<Task> tasks = taskService.createTaskQuery().taskCandidateGroup("boss").list();// 总经理组的任务
        System.out.println("总经理组的任务：" + tasks.size());
        for (Task task : tasks) {
            System.out.println("manager的任务taskname:" + task.getName() + ",id:" + task.getId());
            taskService.claim(task.getId(), "王五");//申领任务 
            taskService.setVariable(task.getId(), "flag", true);//true批准,false不批准
            Object applyUser = taskService.getVariable(task.getId(), "employeeId");
            Object day = taskService.getVariable(task.getId(), "day");
            System.out.println(String.format("%s请假%s天", applyUser, day));
            taskService.complete(task.getId());//完成任务 
        }
        System.out.println("***************总经理组审批流程结束***************");
    }
}    

　　依次运行deploy()、start()、apply()方法之后，因为申请的请假天数为4天，所以流程已经到了总经理角色，此时运行step2Boss()方法，一个完整的请假流程就已经完成。运行结果如下图所示：

　　

　　也可对代码进行修改，总经理不批准

　taskService.setVariable(task.getId(), "flag", false);

　流程就回到员工那里，员工继续申请，设置天数为2

taskService.setVariable(task.getId(), "day", 4);//设置请假天数

　　此时流程到达经理角色，经理批准，流程也就结束

　taskService.setVariable(task.getId(), "flag", true);