code: public static CompressionMetadata create(String dataFilePath, FileSystem fs) {
          Descriptor desc = Descriptor.fromFilename(dataFilePath);
          try {
              return new CompressionMetadata(desc.filenameFor(Component.COMPRESSION_INFO), fs.getFileStatus(new Path(dataFilePath)).getLen(), fs);
          } catch (IOException e) {
              throw new RuntimeException(e);
          }
      }
docs: Create metadata about given compressed file including uncompressed data length, chunk size
  and list of the chunk offsets of the compressed data.
  <p/>
  This is an expensive operation! Don't create more than one for each
  sstable.
  
  @param dataFilePath Path to the compressed file
  @return metadata about given compressed file.