@Override public Optional<ParquetDataColumnReader> visit(
              DecimalLogicalTypeAnnotation logicalTypeAnnotation) {
            final short scale = (short) logicalTypeAnnotation.getScale();
            return isDict ? Optional
                .of(new TypesFromDecimalPageReader(dictionary, length, scale, hivePrecision,
                    hiveScale)) : Optional
                .of(new TypesFromDecimalPageReader(valuesReader, length, scale, hivePrecision,
                    hiveScale));
          }
The reader who reads from the underlying UTF8 string.
ql/src/java/org/apache/hadoop/hive/ql/io/parquet/vector/ParquetDataColumnReaderFactory.java