code: public Observable<Page<ProjectTaskInner>> listNextAsync(final String nextPageLink) {
          return listNextWithServiceResponseAsync(nextPageLink)
              .map(new Func1<ServiceResponse<Page<ProjectTaskInner>>, Page<ProjectTaskInner>>() {
                  @Override
                  public Page<ProjectTaskInner> call(ServiceResponse<Page<ProjectTaskInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Get tasks in a service.
  The services resource is the top-level resource that represents the Data Migration Service. This method returns a list of tasks owned by a service resource. Some tasks may have a status of Unknown, which indicates that an error occurred while querying the status of that task.
  
  @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;ProjectTaskInner&gt; object