Issues converting csv to xls in Java? Only core Java experience needed - question not related to import

Question

First of all, I understand that it\'s unusual that I want to up-convert like this, but please bear with me. We get these csv files via website export and we have no options

Answer 1

Just check the CSV char by char and set a toggle whenever a quote occurs. Here's a kickoff example:

public static List> parseCsv(InputStream input, char separator) 
    throws IOException 
{
    BufferedReader reader = null;
    List> csv = new ArrayList>();
    try {
        reader = new BufferedReader(new InputStreamReader(input, "UTF-8"));
        for (String record; (record = reader.readLine()) != null;) {
            boolean quoted = false;
            StringBuilder fieldBuilder = new StringBuilder();
            List fields = new ArrayList();
            for (int i = 0; i < record.length(); i++) {
                char c = record.charAt(i);
                fieldBuilder.append(c);
                if (c == '"') {
                    quoted = !quoted;
                }
                if ((!quoted && c == separator) || i + 1 == record.length()) {
                    fields.add(fieldBuilder.toString().replaceAll(separator + "$", "")
                        .replaceAll("^\"|\"$", "").replace("\"\"", "\"").trim());
                    fieldBuilder = new StringBuilder();
                }
            }
            csv.add(fields);
        }
    } finally {
        if (reader != null) try { reader.close(); } catch (IOException logOrIgnore) {}
    }
    return csv;
}

You can however also just grab any 3rd party Java CSV API which may have some more features and so on.