code: public Observable<ContentKeyPolicyInner> updateAsync(String resourceGroupName, String accountName, String contentKeyPolicyName, ContentKeyPolicyInner parameters) {
          return updateWithServiceResponseAsync(resourceGroupName, accountName, contentKeyPolicyName, parameters).map(new Func1<ServiceResponse<ContentKeyPolicyInner>, ContentKeyPolicyInner>() {
              @Override
              public ContentKeyPolicyInner call(ServiceResponse<ContentKeyPolicyInner> response) {
                  return response.body();
              }
          });
      }
docs: Update a Content Key Policy.
  Updates an existing Content Key Policy in the Media Services account.
  
  @param resourceGroupName The name of the resource group within the Azure subscription.
  @param accountName The Media Services account name.
  @param contentKeyPolicyName The Content Key Policy name.
  @param parameters The request parameters
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the ContentKeyPolicyInner object