code: public Observable<WorkflowTriggerInner> getAsync(String resourceGroupName, String workflowName, String triggerName) {
          return getWithServiceResponseAsync(resourceGroupName, workflowName, triggerName).map(new Func1<ServiceResponse<WorkflowTriggerInner>, WorkflowTriggerInner>() {
              @Override
              public WorkflowTriggerInner call(ServiceResponse<WorkflowTriggerInner> response) {
                  return response.body();
              }
          });
      }
docs: Gets a workflow trigger.
  
  @param resourceGroupName The resource group name.
  @param workflowName The workflow name.
  @param triggerName The workflow trigger name.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the WorkflowTriggerInner object