public StreamResource buildStreamResource(
ProcessInstance processInstance,
RepositoryService repositoryService,
RuntimeService runtimeService) {
StreamResource imageResource = null;
ProcessDefinitionEntity processDefinition =
(ProcessDefinitionEntity)
((RepositoryServiceImpl) repositoryService)
.getDeployedProcessDefinition(processInstance.getProcessDefinitionId());
if (processDefinition != null && processDefinition.isGraphicalNotationDefined()) {
InputStream definitionImageStream =
ProcessDiagramGenerator.generateDiagram(
processDefinition,
"png",
runtimeService.getActiveActivityIds(processInstance.getId()));
StreamSource streamSource = new InputStreamStreamSource(definitionImageStream);
// Create image name
String imageExtension = extractImageExtension(processDefinition.getDiagramResourceName());
String fileName = processInstance.getId() + UUID.randomUUID() + "." + imageExtension;
imageResource = new StreamResource(streamSource, fileName, ExplorerApp.get());
}
return imageResource;
}
/**
* 显示图片
*
* @return
*/
@RequestMapping(value = "/viewPic.do")
public void viewPic(
HttpServletRequest request,
HttpServletResponse response,
@RequestParam("executionId") String executionId)
throws Exception {
ProcessInstance processInstance =
runtimeService.createProcessInstanceQuery().processInstanceId(executionId).singleResult();
BpmnModel bpmnModel = repositoryService.getBpmnModel(processInstance.getProcessDefinitionId());
List<String> activeActivityIds = runtimeService.getActiveActivityIds(executionId);
// 使用spring注入引擎请使用下面的这行代码
Context.setProcessEngineConfiguration(processEngine.getProcessEngineConfiguration());
InputStream imageStream =
ProcessDiagramGenerator.generateDiagram(bpmnModel, "png", activeActivityIds);
// 输出资源内容到相应对象
byte[] b = new byte[1024];
int len;
while ((len = imageStream.read(b, 0, 1024)) != -1) {
response.getOutputStream().write(b, 0, len);
}
}