Master Flowable: Deploy, Model, and Integrate a Complete Workflow Engine

1. Deploy flowable‑ui

Download Flowable 6.6.0 from the official site, extract the flowable‑ui.war file and place it in Tomcat's webapps directory. Start Tomcat and open http://localhost:8080/flowable‑ui, then log in with the default account admin/test. Edit flowable‑default.properties to point to a local MySQL database.

2. Model the process

In the Flowable UI, open APP.MODELER and create a leave‑approval workflow. Define start and end events, sequence flows, exclusive gateways, and user tasks for student, teacher, and principal. After modeling, export the BPMN file for later deployment.

Diagram details

Event : start/end nodes.

Sequence flow : connectors between elements.

Gateway : decision points (diamond shape).

User task : human tasks (rectangle).

Exported BPMN XML:

<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" ...>
  <process id="leave_approval" name="请假审批" isExecutable="true">
    <startEvent id="start" name="开始" flowable:initiator="startuser" flowable:formFieldValidation="true"/>
    <userTask id="stu_task" name="学生" flowable:candidateGroups="stu_group" flowable:formFieldValidation="true"/>
    <sequenceFlow id="flow1" sourceRef="start" targetRef="stu_task"/>
    ...
  </process>
</definitions>

3. Backend project setup

Create a Spring Boot 2.3.0 project (JDK 8) and add the following dependencies:

<parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <version>2.3.0.RELEASE</version>
</parent>

<dependency>
  <groupId>org.flowable</groupId>
  <artifactId>flowable-spring-boot-starter</artifactId>
  <version>6.6.0</version>
</dependency>

<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>5.1.45</version>
</dependency>

Configure the datasource in application.yml:

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/flowable?useSSL=false&characterEncoding=UTF-8&serverTimezone=GMT%2B8
    driver-class-name: com.mysql.jdbc.Driver
    username: root
    password: 123456

4. Database tables

All Flowable tables start with ACT_. The second part indicates the purpose: ACT_RE_: repository tables (static definitions, resources). ACT_RU_: runtime tables (process instances, tasks, variables, jobs). ACT_HI_: history tables (completed instances, variables, tasks). ACT_GE_: generic tables used in multiple contexts.

Key tables include act_ge_bytearray, act_hi_procinst, act_ru_task, act_id_user, etc.

5. Engine API and services

Important services:

RepositoryService : manage deployments and process definitions.

RuntimeService : start new process instances.

IdentityService : manage users and groups.

FormService : optional form handling.

HistoryService : query historic data.

ManagementService : low‑level DB and job management.

DynamicBpmnService : modify deployed processes without redeployment.

Sample Java code demonstrates deployment, starting a process, claiming and completing tasks for student and teacher groups, and querying historic process and task instances.

import lombok.extern.slf4j.Slf4j;
import org.flowable.engine.*;
import org.flowable.task.api.Task;
import org.springframework.beans.factory.annotation.Autowired;

@Slf4j
public class TestFlowable {
    @Autowired private RepositoryService repositoryService;
    @Autowired private RuntimeService runtimeService;
    @Autowired private HistoryService historyService;
    @Autowired private org.flowable.engine.TaskService taskService;
    @Autowired private org.flowable.engine.IdentityService identityService;

    public void createDeploymentZip() {
        // Deploy BPMN zip
        try {
            File zip = new File("f:/leave_approval.bpmn20.zip");
            ZipInputStream zipStream = new ZipInputStream(new FileInputStream(zip));
            Deployment deployment = repositoryService.createDeployment()
                .addZipInputStream(zipStream)
                .deploy();
            log.info("Deployment successful:{}", deployment.getId());
        } catch (FileNotFoundException e) { e.printStackTrace(); }

        // Start process instance
        String processKey = "leave_approval";
        String businessKey = "schoolleave";
        ProcessInstance instance = runtimeService.startProcessInstanceByKey(processKey, businessKey, new HashMap<>());
        log.info("Process started:{}", instance.getId());

        // Student tasks
        List<Task> studentTasks = taskService.createTaskQuery()
            .taskCandidateGroup("stu_group")
            .orderByTaskCreateTime().desc()
            .list();
        for (Task task : studentTasks) {
            taskService.claim(task.getId(), "my");
            taskService.complete(task.getId());
        }

        // Teacher tasks with decision variable
        List<Task> teacherTasks = taskService.createTaskQuery()
            .taskCandidateGroup("te_group")
            .orderByTaskCreateTime().desc()
            .list();
        for (Task task : teacherTasks) {
            taskService.claim(task.getId(), "myte");
            Map<String, Object> vars = new HashMap<>();
            vars.put("command", "agree");
            taskService.complete(task.getId(), vars);
        }

        // History queries
        List<HistoricProcessInstance> historicProcesses = historyService
            .createHistoricProcessInstanceQuery()
            .processDefinitionKey("leave_approval")
            .list();
        List<HistoricTaskInstance> historicTasks = historyService
            .createHistoricTaskInstanceQuery()
            .processDefinitionKey("leave_approval")
            .list();
    }
}

6. References

Flowable documentation translation: https://github.com/qiudaoke/flowable-userguide

Official Flowable demo for version 6.6.0

Blog post: https://www.cnblogs.com/yangjiming/p/10938515.html