private final static Logger logger = Logger.getLogger(SendMailStep.class.getName());
@Override
public String invoke(BpmStep step, Map<String, String> params) throws Exception {
ProcessToolContext ctx = ProcessToolContext.Util.getThreadProcessToolContext();
BpmNotificationService service = ctx.getRegistry().getRegisteredService(BpmNotificationService.class);
Map<String, Object> data = new HashMap<String, Object>();
String processId = step.getProcessInstance().getExternalKey();
if (!Strings.hasText(processId))
processId = step.getProcessInstance().getInternalId();