docs: public Observable<JobTargetGroupInner> getAsync(String resourceGroupName, String serverName, String jobAgentName, String targetGroupName) {
          return getWithServiceResponseAsync(resourceGroupName, serverName, jobAgentName, targetGroupName).map(new Func1<ServiceResponse<JobTargetGroupInner>, JobTargetGroupInner>() {
              @Override
              public JobTargetGroupInner call(ServiceResponse<JobTargetGroupInner> response) {
                  return response.body();
              }
          });
      }