code: public void resumeWorkflow(String workflowId) {
          Preconditions.checkArgument(StringUtils.isNotBlank(workflowId), "workflow id cannot be blank");
          stub.resumeWorkflow(WorkflowServicePb.ResumeWorkflowRequest.newBuilder()
                  .setWorkflowId(workflowId)
                  .build()
          );
      }
docs: Resume a paused workflow by workflow id
  
  @param workflowId the workflow id of the paused workflow