@Override
    public void processWatermark(Watermark mark) throws Exception {
        if (propagateWatermark || Watermark.MAX_WATERMARK.equals(mark)) {
            super.processWatermark(mark);
        }
    }
@Test
    public void testWatermarkSuppression() throws Exception {
        final InputConversionOperator<Row> operator =
                new InputConversionOperator<>(
                        createConverter(DataTypes.ROW(DataTypes.FIELD("f", DataTypes.INT()))),
                        false,
                        false,
                        false,
                        true);

        // would throw an exception otherwise because an output is not set
        operator.processWatermark(new Watermark(1000));
    }