<dependency>
  <groupId>org.activiti</groupId>
  <artifactId>activiti-image-generator</artifactId>
  <version>5.22.0</version>
</dependency>

//這個類在5.22.0往上的版本中才有
DefaultProcessDiagramGenerator diagramGenerator=new DefaultProcessDiagramGenerator();

  @Test
  public void test1() throws Exception {
    
    //根據(jù)流程定義id來獲取BpmnModel對象
    String processDefinitionId="process:2:4304";
    BpmnModel bpmnModel = repositoryService.getBpmnModel(processDefinitionId);
    //這個類在5.22.0往上的版本中才有
    DefaultProcessDiagramGenerator diagramGenerator=new DefaultProcessDiagramGenerator();
    //繪制bpmnModel代表的流程的流程圖
    InputStream inputStream = diagramGenerator.generateDiagram(bpmnModel, "png", new ArrayList<String>());
    FileOutputStream output=new FileOutputStream(new File("d:/test.png"));
    IOUtils.copy(inputStream, output);
    System.out.println("輸出完成");
  }

String executionId=processInstance.getId();
List<String> activeActivityIds = runtimeService.getActiveActivityIds(executionId);

//得到已經(jīng)走過的節(jié)點的id集合
    HistoricActivityInstanceQuery historicActivityInstanceQuery = historyService.createHistoricActivityInstanceQuery();
    List<HistoricActivityInstance> historicActivityInstanceList = historicActivityInstanceQuery.processInstanceId(processInstanceId).list();
    for(HistoricActivityInstance hi:historicActivityInstanceList) {
      String taskKey=hi.getActivityId();
      activeActivityIds.add(taskKey);
    }

DefaultProcessDiagramGenerator defaultProcessDiagramGenerator=new DefaultProcessDiagramGenerator();
//獲取流程圖的輸入流
InputStream inputStream = defaultProcessDiagramGenerator.generateDiagram(bpmnModel, "png", activeActivityIds);
//輸出圖片到指定路徑
IOUtils.copy(inputStream, new FileOutputStream(new File("d:/test2.png")));
System.out.println("輸出成功");