java - How to read Excel(.xlsx) Multipartfile using Apache CSV Parser?. Current approach not working with CSVFormat set to EXCEL

Question

I'm trying to read records for both CSV as well as Excel format using Apache CSVParser. Below is my approach for the same.

try (BufferedReader reader = new BufferedReader(new InputStreamReader(file.getInputStream(),
                                                                              StandardCharsets.UTF_8)) {
            CSVParser parser;
            String extension = StringUtils.getFilenameExtension(file.getOriginalFilename());
            logger.info("Extension Detected : {}", extension);
            if (extension != null && extension.equals("xlsx")) {
                parser = new CSVParser(reader,
                                       CSVFormat.EXCEL.withFirstRecordAsHeader().withTrim());
            } else if(extension != null && extension.equals("csv")){
                parser = new CSVParser(reader, CSVFormat.DEFAULT.withFirstRecordAsHeader()
                                                                .withIgnoreHeaderCase().withTrim());
            } else {
                throw new InvalidRequestException(Collections.singletonList(INVALID_EXTENSION));
            }
            logger.info("Records parsed successfully for file : {}", file.getOriginalFilename());
            return parser.getRecords();
        } catch (IOException e) {
            throw new FileReadException(e);
        }

This is working for CSV Files but not for Excel. Parser is not able to read the records properly. Here's the debugged value of parser.

I feel it's related to reusableToken because in case of CSV, Token Type is TOKEN , But in case of Excel it's EORecord.

Can anybody please help?

Answer 1

Apache CSVParser can't parse Excel files, only csv files. Using the CSVFormat.EXCEL parameter just tells CSVParser that the csv file was created/exported using Excel.

To read xls & xlsx files you need to use Apache POI.