How to get Distinct count from parquet file without reading whole file Using Java ParquetFileReader

Question

I need to get information like get maximum length of a string if the type is string and distinct count from parquet without reading the whole file in Java not using Avro Parquet reader.

ParquetFileReader parquetFileReader = ParquetFileReader.open(inputFile);

List<BlockMetaData> fileMetaData = parquetFileReader.getFooter().getBlocks();

In this block metaData holds only stats like min max value or row count. I need distinct count and in case of String types max length String.