How to differentiate between empty string and null with OpenCSV

java null opencsv
Gavriel picture Gavriel · Aug 14, 2014 · Viewed 12.3k times · Source

This is my code:

CSVReader reader = new CSVReader(isReader);
while ((col = reader.readNext()) != null) {
   String c1 = col[1];
}

this is my csv file:

"a","","c"
"1",,"3"

Is there a way I can differentiate between null and ""? OpenCSV seems to treat everything as non-null String. Can I tell it to treat empty fields as null?

Answer

Cary Li picture Cary Li · Jan 12, 2016

Adding to @Gavriel's answer, starting from OpenCSV 3.6 (maybe earlier), I found that strictQuotes doesn't help with returning null anymore.

CSVReaderBuilder has withFieldAsNull() for this purpose.

CSVReader csvReader = new CSVReaderBuilder(csvFileReader)
    .withFieldAsNull(CSVReaderNullFieldIndicator.EMPTY_SEPARATORS)
    .build();

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