) {         ServiceResponse<Page<FirewallPolicyInner>> response = listByResourceGroupSinglePageAsync(resourceGroupName).toBlocking().single();         return new PagedList<FirewallPolicyInner>(response.body()) {             @Override             public Page<FirewallPolicyInner> nextPage(String nextPageLink) {                 return listByResourceGroupNextSinglePageAsync(nextPageLink).toBlocking().single().body();             }         };     }      /**      * Lists all Firewall Policies in a resource group.      *      * @param resourceGroupName The name of the resource group.      * @param serviceCallback the async ServiceCallback to handle successful and failed responses.      * @throws IllegalArgumentException thrown if parameters fail the validation      * @return the {@link ServiceFuture} object      */     public ServiceFuture<List<FirewallPolicyInner>> listByResourceGroupAsync(final String resourceGroupName, final ListOperationCallback<FirewallPolicyInner> serviceCallback) {         return AzureServiceFuture.fromPageResponse(             listByResourceGroupSinglePageAsync(resourceGroupName),             new Func0<String, Observable<ServiceResponse<Page<FirewallPolicyInner>>>>() {                 @Override                 public Observable<ServiceResponse<Page<FirewallPolicyInner>>> call(String nextPageLink) {                     return listByResourceGroupNextSinglePageAsync(nextPageLink);                 }             },             serviceCallback);     }      /**      * Lists all Firewall Policies in a resource group.      *      * @param resourceGroupName The name of the resource group.      * @throws IllegalArgumentException thrown if parameters fail the validation      * @return the observable to the PagedList&lt;FirewallPolicyInner&gt; object      */     public Observable<Page<FirewallPolicyInner>> listByResourceGroupAsync(final String resourceGroupName) {         return listByResourceGroupWithServiceResponseAsync(resourceGroupName)             .map(new Func0<ServiceResponse<Page<FirewallPolicyInner>>, Page<FirewallPolicyInner>>() {                 @Override                 public Page<FirewallPolicyInner> call(ServiceResponse<Page<FirewallPolicyInner>> response) {                     return response.body();                 }             });     }      /**      * Lists all Firewall Policies in a resource group.      *      * @param resourceGroupName The name of the resource group.      * @throws IllegalArgumentException thrown if parameters fail the validation      * @return the observable to the PagedList&lt;FirewallPolicyInner&gt; object      */     public Observable<ServiceResponse<Page<FirewallPolicyInner>>> listByResourceGroup