How split line by comma when comma is included inside in java

Question

I want to split text that must fit to csv syntax but the text contains comma

Example: account id title text

String line = "account123,2222,Thnaks for reaching out,\"Hey [[customerFirstName]], Thanks for reaching out to us.\""

String[] splitted = line.split(",");

Result:

splitted = {String[5]@539} 
 0 = "account123"
 1 = "2222"
 2 = "Thnaks for reaching out"
 3 = ""Hey [[customerFirstName]]"
 4 = " Thanks for reaching out to us.""

But I expect

splitted = {String[4]@539} 
             0 = "account123"
             1 = "2222"
             2 = "Thnaks for reaching out"
             3 = "Hey [[customerFirstName]], Thanks for reaching out to us.\"

This question comes up often here, not only in Java, but across basically every language tag. The usual way to deal with this is to escape each field with a special character, e.g. escape each CSV field with double quotes. — Tim Biegeleisen, Aug 01 '18 at 14:13
the Java `.split()` has a second argument which is the "limit". In your case above you could use ... `.split(",", 3)` — 7 Reeds, Aug 01 '18 at 14:14
take a look here: https://www.mkyong.com/java/how-to-read-and-parse-csv-file-in-java/ — Luca Di Liello, Aug 01 '18 at 14:14
Consider using CSV parser library, take a look at [commons-csv](https://commons.apache.org/proper/commons-csv/) or [opencsv](http://opencsv.sourceforge.net/) — Vladimir Vagaytsev, Aug 01 '18 at 14:19
read this https://stackoverflow.com/questions/18893390/splitting-on-comma-outside-quotes — Youcef LAIDANI, Aug 01 '18 at 14:20
I dont want to use libraries (its a production code ) ..do you have concrete solution , maybe regex ? — VitalyT, Aug 01 '18 at 14:20
[`String line = "account123,2222,Thnaks for reaching out,\"Hey [[customerFirstName]], Thanks for reaching out to us.\""; String[] split = line.split(",(?=(?:[^\"]*\"[^\"]*\")*[^\"]*$)"); Arrays.stream(split) .forEach(System.out::println);`](https://ideone.com/kaCIWn) — Youcef LAIDANI, Aug 01 '18 at 14:24

score 1 · Answer 1 · answered Aug 01 '18 at 14:21

Your solution is, as you have found, very brittle. The good news is that there are a number of more robust CSV solutions available. For purposes of this answer, I'll use openCSV, where your reading code becomes:

CSVReader csvReader = new CSVReader(reader);
List<String[]> list = csvReader.readAll();
reader.close();
csvReader.close();

Hope that helps...

score 0 · Answer 2 · answered Aug 01 '18 at 14:43

Here is a simple solution:

public static void main(String... args) {
    String line = "account123,2222,Thnaks for reaching out,\"Hey [[customerFirstName]], Thanks for reaching out to us.\",\"Hey [[customerFirstName]], Thanks for reaching out to us.\"";
    for (String s : splitByComma(line)) {
        System.out.println(s);
    }
}

private static List<String> splitByComma(String line) {
    String[] words = line.split(",");
    List<String> list = new ArrayList<>();
    for (int i = 0; i < words.length; ++i) {
        if (words[i].startsWith("\"")) { // collect from the start of the cell;
            String s = words[i].substring(1);
            while (i < words.length - 1) {
                s += "," + words[++i].substring(0, words[i].length() - 1);
                if (words[i++].endsWith("\"")) break; // jump out of the cell after the closing double quotes;
            }
            list.add(s);
            i--;
        } else {
            list.add(words[i]);
        }
    }
    return list;
}

And your output will be:

account123
2222
Thnaks for reaching out
Hey [[customerFirstName]], Thanks for reaching out to us.
Hey [[customerFirstName]], Thanks for reaching out to us.

this regex split("(?=(?:[^"]*"[^"]*")*[^"]*$) ") works for me :) — VitalyT, Aug 01 '18 at 15:40
@VitalyT don't get me wrong here... but you yourself have used a regex... ;) — Eugene, Aug 02 '18 at 09:24

How split line by comma when comma is included inside in java

2 Answers2