code: public Observable<Page<ProjectFileInner>> listNextAsync(final String nextPageLink) {
          return listNextWithServiceResponseAsync(nextPageLink)
              .map(new Func1<ServiceResponse<Page<ProjectFileInner>>, Page<ProjectFileInner>>() {
                  @Override
                  public Page<ProjectFileInner> call(ServiceResponse<Page<ProjectFileInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Get files in a project.
  The project resource is a nested resource representing a stored migration project. This method returns a list of files owned by a project resource.
  
  @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;ProjectFileInner&gt; object