code: public ServiceFuture<RedisFirewallRuleInner> getAsync(String resourceGroupName, String cacheName, String ruleName, final ServiceCallback<RedisFirewallRuleInner> serviceCallback) {
          return ServiceFuture.fromResponse(getWithServiceResponseAsync(resourceGroupName, cacheName, ruleName), serviceCallback);
      }
docs: Gets a single firewall rule in a specified redis cache.
  
  @param resourceGroupName The name of the resource group.
  @param cacheName The name of the Redis cache.
  @param ruleName The name of the firewall rule.
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object