工作流引擎

Activiti&Flowable

工作流引擎

ProcessEngine对象，这是Activiti工作的核心。负责生成流程运行时的各种实例及数据、监控和管理流程的运行。

BPMN

业务流程建模与标注（Business Process Model and Notation，BPMN) ，描述流程的基本符号，包括这些图元如何组合成一个业务流程图（Business Process Diagram）

实现

1. 配置数据库
2. 画（配置）流程图

SpringBoot-Flowable

1. 添加依赖

   <dependencies>
           <dependency>
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-starter-web</artifactId>
           </dependency>
           <!--flowable工作流依赖-->
           <dependency>
               <groupId>org.flowable</groupId>
               <artifactId>flowable-spring-boot-starter</artifactId>
               <version>6.3.0</version>
           </dependency>
           <!--mysql依赖-->
           <dependency>
               <groupId>mysql</groupId>
               <artifactId>mysql-connector-java</artifactId>
               <version>5.1.45</version>
           </dependency>
   </dependencies>
   

2. Flowable配置

   spring:
     datasource:
       url: jdbc:mysql://127.0.0.1:3306/flowable-spring-boot?characterEncoding=UTF-8
       username: root
       password: root
   flowable:
   #关闭定时任务JOB
     async-executor-activate: false
   

3. 定义流程文件

   The Flowable engine expects processes to be defined in the BPMN 2.0 format, which is an XML standard that is widely accepted in the industry. Typically, such a process definition is modeled with a visual modeling tool, such as the Flowable Designer (Eclipse) or the Flowable Modeler (web application).

   flowable建议采用业界标准BPMN2.0的XML来描述需要定义的工作流。 可以使用流程建模工具生成xxx.bpmn20.xml文件。

   核心逻辑在于process标签内。包括各个节点以及每条流程线。

4. 测试

   首先创建一个Controller：自动注入Flowable框架的几个Bean

   @Controller
   @RequestMapping(value = "expense")
   public class ExpenseController {
       @Autowired
       private RuntimeService runtimeService;
       @Autowired
       private TaskService taskService;
       @Autowired
       private RepositoryService repositoryService;
       @Autowired
       private ProcessEngine processEngine;
   /***************此处为业务代码******************/
   }
   

   1. 启动流程

      @RequestMapping(value = "add")
          @ResponseBody
          public String addExpense(String userId, Integer money, String descption) {
              //启动流程
              HashMap<String, Object> map = new HashMap<>();
              map.put("taskUser", userId);
              map.put("money", money);
              ProcessInstance processInstance = runtimeService
                  .startProcessInstanceByKey("Expense", map);
              return "提交成功.流程Id为：" + processInstance.getId();
          } 
      

   2. 查询流程列表和代办列表

      @RequestMapping(value = "/list")
          @ResponseBody
          public Object list(String userId) {
              List<Task> tasks = taskService.createTaskQuery()
                  .taskAssignee(userId)
                  .orderByTaskCreateTime()
                  .desc()
                  .list();
              for (Task task : tasks) {
                  System.out.println(task.toString());
              }
              return tasks.toArray().toString();
          }
      

   3. 审批

      @RequestMapping(value = "apply")
          @ResponseBody
          public String apply(String taskId) {
              Task task = taskService
                  .createTaskQuery()
                  .taskId(taskId)
                  .singleResult();
              if (task == null) {
                  throw new RuntimeException("流程不存在");
              }
              //通过审核
              HashMap<String, Object> map = new HashMap<>();
              map.put("outcome", "通过");
              taskService.complete(taskId, map);
              return "processed ok!";
          } 
      

   4. 生成流程图

      /**
           * 生成流程图
           *
           * @param processId 任务ID
           */
          @RequestMapping(value = "processDiagram")
          public void genProcessDiagram(HttpServletResponse httpServletResponse, String processId) throws Exception {
              ProcessInstance pi = runtimeService.createProcessInstanceQuery().processInstanceId(processId).singleResult();
       
              //流程走完的不显示图
              if (pi == null) {
                  return;
              }
              Task task = taskService.createTaskQuery().processInstanceId(pi.getId()).singleResult();
              //使用流程实例ID，查询正在执行的执行对象表，返回流程实例对象
              String InstanceId = task.getProcessInstanceId();
              List<Execution> executions = runtimeService
                      .createExecutionQuery()
                      .processInstanceId(InstanceId)
                      .list();
       
              //得到正在执行的Activity的Id
              List<String> activityIds = new ArrayList<>();
              List<String> flows = new ArrayList<>();
              for (Execution exe : executions) {
                  List<String> ids = runtimeService.getActiveActivityIds(exe.getId());
                  activityIds.addAll(ids);
              }
       
              //获取流程图
              BpmnModel bpmnModel = repositoryService.getBpmnModel(pi.getProcessDefinitionId());
              ProcessEngineConfiguration engconf = processEngine.getProcessEngineConfiguration();
              ProcessDiagramGenerator diagramGenerator = engconf.getProcessDiagramGenerator();
              InputStream in = diagramGenerator.generateDiagram(bpmnModel, "png", activityIds, flows, engconf.getActivityFontName(), engconf.getLabelFontName(), engconf.getAnnotationFontName(), engconf.getClassLoader(), 1.0);
              OutputStream out = null;
              byte[] buf = new byte[1024];
              int legth = 0;
              try {
                  out = httpServletResponse.getOutputStream();
                  while ((legth = in.read(buf)) != -1) {
                      out.write(buf, 0, legth);
                  }
              } finally {
                  if (in != null) {
                      in.close();
                  }
                  if (out != null) {
                      out.close();
                  }
              }
          }