flowable一个简单的例子

holiday-request.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: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"
             xmlns:activiti="http://activiti.org/bpmn"
             typeLanguage="http://www.w3.org/2001/XMLSchema"
             expressionLanguage="http://www.w3.org/1999/XPath"
             targetNamespace="http://www.flowable.org/processdef">

    <process id="holidayRequest" name="Holiday Request" isExecutable="true">

        <startEvent id="startEvent"/>
        <sequenceFlow sourceRef="startEvent" targetRef="approveTask"/>

        <userTask id="approveTask" name="Approve or reject request" activiti:candidateGroups="managers"/>
        <sequenceFlow sourceRef="approveTask" targetRef="decision"/>

        <exclusiveGateway id="decision"/>
        <sequenceFlow sourceRef="decision" targetRef="externalSystemCall">
            <conditionExpression xsi:type="tFormalExpression">
                <![CDATA[
                  ${approved}
                ]]>
            </conditionExpression>
        </sequenceFlow>
        <sequenceFlow  sourceRef="decision" targetRef="sendRejectionMail">
            <conditionExpression xsi:type="tFormalExpression">
                <![CDATA[
                  ${!approved}
                ]]>
            </conditionExpression>
        </sequenceFlow>

        <serviceTask id="externalSystemCall" name="Enter holidays in external system" activiti:class="com.sky.flowable.CallExternalSystemDelegate"/>
        <sequenceFlow sourceRef="externalSystemCall" targetRef="holidayApprovedTask"/>

        <userTask id="holidayApprovedTask" name="Holiday approved" activiti:assignee="${employee}"/>
        <sequenceFlow sourceRef="holidayApprovedTask" targetRef="approveEnd"/>

        <serviceTask id="sendRejectionMail" name="Send out rejection email" activiti:class="com.sky.flowable.SendRejectionMail"/>
        <sequenceFlow sourceRef="sendRejectionMail" targetRef="rejectEnd"/>

        <endEvent id="approveEnd"/>

        <endEvent id="rejectEnd"/>

    </process>

</definitions>

main：

package com.sky.flowable;

import org.activiti.engine.*;
import org.activiti.engine.history.HistoricActivityInstance;
import org.activiti.engine.impl.cfg.StandaloneProcessEngineConfiguration;
import org.activiti.engine.repository.Deployment;
import org.activiti.engine.repository.ProcessDefinition;
import org.activiti.engine.runtime.ProcessInstance;
import org.activiti.engine.task.Task;

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

/**
 * @author sky
 * @version 1.0
 * @since 4.0
 */
public class main {
    public static void main(String[] args) {
        ProcessEngineConfiguration cfg = new StandaloneProcessEngineConfiguration()
                .setJdbcUrl("jdbc:h2:mem:flowable;DB_CLOSE_DELAY=-1")
                .setJdbcUsername("sa")
                .setJdbcPassword("")
                .setJdbcDriver("org.h2.Driver")
                .setDatabaseSchemaUpdate(ProcessEngineConfiguration.DB_SCHEMA_UPDATE_TRUE);

        ProcessEngine processEngine = cfg.buildProcessEngine();

        /*创建了一个新的部署*/
        RepositoryService repositoryService = processEngine.getRepositoryService();
        Deployment deployment = repositoryService.createDeployment()
                .addClasspathResource("holiday-request.bpmn20.xml")     //TODO holiday.xml命名为何不行?
                .deploy();

        /*部署流程定义*/
        ProcessDefinition processDefinition = repositoryService.createProcessDefinitionQuery()
                .deploymentId(deployment.getId())
                .singleResult();
        System.out.println("Found process definition : " + processDefinition.getName());

        Scanner scanner= new Scanner(System.in);
        System.out.println("Who are you?");
        String employee = scanner.nextLine();
        System.out.println("How many holidays do you want to request?");
        Integer nrOfHolidays = Integer.valueOf(scanner.nextLine());
        System.out.println("Why do you need them?");
        String description = scanner.nextLine();

        RuntimeService runtimeService = processEngine.getRuntimeService();
        /*参数传递*/
        Map<String, Object> variables = new HashMap<String, Object>();
        variables.put("employee", employee);
        variables.put("nrOfHolidays", nrOfHolidays);
        variables.put("description", description);
        /*通过RuntimeService启动流程实例*/
        ProcessInstance processInstance =
                runtimeService.startProcessInstanceByKey("holidayRequest", variables);

        /*得到实际的“managers”组任务列表*/
        TaskService taskService = processEngine.getTaskService();
        List<Task> tasks = taskService.createTaskQuery().taskCandidateGroup("managers").list();
        System.out.println("You have " + tasks.size() + " tasks:");
        for (int i=0; i<tasks.size(); i++) {
            System.out.println((i+1) + ") " + tasks.get(i).getName());
        }

        /*获取特定的流程实例变量*/
        System.out.println("Which task would you like to complete?");
        int taskIndex = Integer.valueOf(scanner.nextLine());
        Task task = tasks.get(taskIndex - 1);
        Map<String, Object> processVariables = taskService.getVariables(task.getId());
        System.out.println(processVariables.get("employee") + " wants " + processVariables.get("nrOfHolidays") + " of holidays. Do you approve this?");

        /*完成任务，传递排他网关条件*/
        boolean approved = scanner.nextLine().toLowerCase().equals("y");
        variables = new HashMap<String, Object>();
        variables.put("approved", approved);
        taskService.complete(task.getId(), variables);

        /*只有一个特定流程实例的活动
          只有完成的活动
          按结束时间排序*/
        HistoryService historyService = processEngine.getHistoryService();
        List<HistoricActivityInstance> activities =
                historyService.createHistoricActivityInstanceQuery()
                        .processInstanceId(processInstance.getId())
                        .finished()
                        .orderByHistoricActivityInstanceEndTime().asc()
                        .list();
        for (HistoricActivityInstance activity : activities) {
            System.out.println(activity.getActivityId() + " took "
                    + activity.getDurationInMillis() + " milliseconds");
        }
    }
}

CallExternalSystemDelegate ：

public class CallExternalSystemDelegate implements JavaDelegate {
    public void execute(DelegateExecution execution) {
        System.out.println("Calling the external system for employee "
                + execution.getVariable("employee"));
    }
}

SendRejectionMail ：

public class SendRejectionMail implements JavaDelegate {
    public void execute(DelegateExecution execution) {
        System.out.println("Calling the external system for employee "
                + execution.getVariable("employee") + "   Rejection---------------------");
    }
}