code: public Observable<ServerKeyInner> getAsync(String resourceGroupName, String serverName, String keyName) {
          return getWithServiceResponseAsync(resourceGroupName, serverName, keyName).map(new Func1<ServiceResponse<ServerKeyInner>, ServerKeyInner>() {
              @Override
              public ServerKeyInner call(ServiceResponse<ServerKeyInner> response) {
                  return response.body();
              }
          });
      }
docs: Gets a server key.
  
  @param resourceGroupName The name of the resource group that contains the resource. You can obtain this value from the Azure Resource Manager API or the portal.
  @param serverName The name of the server.
  @param keyName The name of the server key to be retrieved.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the ServerKeyInner object