code: public Observable<ExpressRouteCrossConnectionPeeringInner> createOrUpdateAsync(String resourceGroupName, String crossConnectionName, String peeringName, ExpressRouteCrossConnectionPeeringInner peeringParameters) {
          return createOrUpdateWithServiceResponseAsync(resourceGroupName, crossConnectionName, peeringName, peeringParameters).map(new Func1<ServiceResponse<ExpressRouteCrossConnectionPeeringInner>, ExpressRouteCrossConnectionPeeringInner>() {
              @Override
              public ExpressRouteCrossConnectionPeeringInner call(ServiceResponse<ExpressRouteCrossConnectionPeeringInner> response) {
                  return response.body();
              }
          });
      }
docs: Creates or updates a peering in the specified ExpressRouteCrossConnection.
  
  @param resourceGroupName The name of the resource group.
  @param crossConnectionName The name of the ExpressRouteCrossConnection.
  @param peeringName The name of the peering.
  @param peeringParameters Parameters supplied to the create or update ExpressRouteCrossConnection peering operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable for the request