code: public Observable<VirtualMachineExtensionsListResultInner> getExtensionsAsync(String resourceGroupName, String vmName, String expand) {
          return getExtensionsWithServiceResponseAsync(resourceGroupName, vmName, expand).map(new Func1<ServiceResponse<VirtualMachineExtensionsListResultInner>, VirtualMachineExtensionsListResultInner>() {
              @Override
              public VirtualMachineExtensionsListResultInner call(ServiceResponse<VirtualMachineExtensionsListResultInner> response) {
                  return response.body();
              }
          });
      }
docs: The operation to get all extensions of a Virtual Machine.
  
  @param resourceGroupName The name of the resource group.
  @param vmName The name of the virtual machine containing the extension.
  @param expand The expand expression to apply on the operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the VirtualMachineExtensionsListResultInner object