Reading existing csv and then writing back to CSV puts inches expressed as double quotes in a cell as "" instead of \"

Question

I have a CSV that I generate by building StringBuilder and writing to using PrintWriter. Then I read that CSV again and append something to it, but it messes up the cell which has double quotes in it, used to denote inches. It prints double-quotes twice as 15"

One of the values being added to StringBuilder is this:

Code 1.1

String title = "Poly Nuclear 15\" Laptop Series Notebook Intel Windows10+ 7.6V Battery 8GB Memory"
Text t1 = new Text();
t1.setContent(title);

if (title.contains("\"")) {
      t1.setContent("Poly Nuclear 15\\\" Laptop Series Notebook Intel Windows10+ 7.6V Battery 8GB Memory");
}

My first output (after writing comma separated String created using StringBuilder) using PrintWriter is this:

OutputStreamWriter outputStreamWriter = new OutputStreamWriter(new FileOutputStream(filename, true), StandardCharsets.UTF_8);
PrintWriter printWriter = new PrintWriter(outputStreamWriter);
printWriter.println(stringBuilder.toString());

key,date,ms_id,title,alertId
190-2,2022-02-20 12:35:09,107193,Poly Nuclear 15"  Laptop Series Notebook Intel Windows10+ 7.6V Battery 8GB Memory,

Code 1.2

Now I am adding the last column's value alertId at the of each row. I am reading and appending to each row, then writing back to CSV as follows:

// Here below method is called as writeBack("1222") with fixed value.
public void writeBack(String value) {
      String filePath = "/dir1/dir2/test.csv";
      String key = "alertId"; // column name for which value needs to be added.
      InputStreamReader inputStreamReader = new InputStreamReader(new 
      FileInputStream(filePath), StandardCharsets.UTF_8);
      CSVReader reader = new CSVReader(inputStreamReader);

      String[] header = reader.readNext();
      int columnNum = Arrays.asList(header).indexOf(key);

      List<String[]> feedData = reader.readAll();
      try {
        for (String[] row : feedData) {
          row[columnNum] = value;
        }
        reader.close();

        OutputStreamWriter outputStreamWriter = new OutputStreamWriter(new FileOutputStream(filePath), StandardCharsets.UTF_8);
        CSVWriter writer = new CSVWriter(outputStreamWriter);
        writer.writeNext(header);
        writer.writeAll(feedData);
        writer.flush();
        writer.close();
      } catch (Exception e) {
        writeLog("ERROR", e);

      }
}

My final output is this where everything is correct except the String value has double quotes as 15""

"key","date","ms_id","title","alertId"
"190-2","2022-02-20 12:35:09","107193","Poly Nuclear 15""  Laptop Series Notebook Intel Windows10+ 7.6V Battery 8GB Memory","1222"

What can I do to avoid double quotes in the final output within the cell that denotes inches?

Expected output

"key","date","ms_id","title","alertId"
"190-2","2022-02-20 12:35:09","107193","Poly Nuclear 15\"  Laptop Series Notebook Intel Windows10+ 7.6V Battery 8GB Memory","1222"

Answer 1

Thank you @Mark Rotteveel for the pointer tip. This helped me to look for a different separator and also escape more characters.

Realized that CSVReader and CSVWriter has different escape characters too.

I finally solved using the follwing:

import org.apache.commons.lang.StringEscapeUtils;
...

StringEscapeUtils.escapeCsv("Poly Nuclear 15\" Laptop Series, Notebook \\ Intel Windows10+ 7.6V Battery 8GB Memory")

And using this while writing:

import com.opencsv.ICSVWriter;
...
char escapeChar = '\\';
CSVWriter writer = new CSVWriter(outputStreamWriter, ICSVWriter.DEFAULT_SEPARATOR, ICSVWriter.DEFAULT_QUOTE_CHARACTER, escapeChar, ICSVWriter.DEFAULT_LINE_END);