code: public static <T> IncreasingQualityDataSourceSupplier<T> create(
        List<Supplier<DataSource<T>>> dataSourceSuppliers, boolean dataSourceLazy) {
      return new IncreasingQualityDataSourceSupplier<T>(dataSourceSuppliers, dataSourceLazy);
    }
docs: Creates a new data source supplier with increasing-quality strategy with optional lazy state
  creation.
  
  <p>Note: for performance reasons the list doesn't get cloned, so the caller of this method
  should not modify the list once passed in here.
  
  @param dataSourceSuppliers list of underlying suppliers
  @param dataSourceLazy if true, the state of data source would be created only if necessary