### Question:
CumulativeSumFlux extends AbstractParametrizedFlux { @Nonnull public CumulativeSumFlux withColumns(@Nonnull final String[] columns) { Arguments.checkNotNull(columns, "columns"); this.withPropertyValue("columns", columns); return this; } CumulativeSumFlux(@Nonnull final Flux source); @Nonnull CumulativeSumFlux withColumns(@Nonnull final String[] columns); @Nonnull CumulativeSumFlux withColumns(@Nonnull final Collection<String> columns);  }### Answer:
@Test void cumulativeSum() { Flux flux = Flux .from("telegraf") .cumulativeSum() .withColumns(new String[]{"_value"}); Assertions.assertThat(flux.toString()) .isEqualToIgnoringWhitespace("from(bucket:\"telegraf\") |> cumulativeSum(columns: [\"_value\"])"); }