code: public Observable<AvailableProvidersListInner> listAvailableProvidersAsync(String resourceGroupName, String networkWatcherName, AvailableProvidersListParameters parameters) {
          return listAvailableProvidersWithServiceResponseAsync(resourceGroupName, networkWatcherName, parameters).map(new Func1<ServiceResponse<AvailableProvidersListInner>, AvailableProvidersListInner>() {
              @Override
              public AvailableProvidersListInner call(ServiceResponse<AvailableProvidersListInner> response) {
                  return response.body();
              }
          });
      }
docs: Lists all available internet service providers for a specified Azure region.
  
  @param resourceGroupName The name of the network watcher resource group.
  @param networkWatcherName The name of the network watcher resource.
  @param parameters Parameters that scope the list of available providers.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable for the request