code: public Observable<Page<ProtectionPolicyResourceInner>> listNextAsync(final String nextPageLink) {
          return listNextWithServiceResponseAsync(nextPageLink)
              .map(new Func1<ServiceResponse<Page<ProtectionPolicyResourceInner>>, Page<ProtectionPolicyResourceInner>>() {
                  @Override
                  public Page<ProtectionPolicyResourceInner> call(ServiceResponse<Page<ProtectionPolicyResourceInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Lists of backup policies associated with Recovery Services Vault. API provides pagination parameters to fetch scoped results.
  
  @param nextPageLink The NextLink from the previous successful call to List operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;ProtectionPolicyResourceInner&gt; object