Result separation with regex

Question

I wrote a parser that reads a file line by line and parses it with a regex statement. (Regex below)

case "countries":
            pattern = "\\\"(.+?)\\\"(\\s+)?(\\((.+?)\\))?(\\s+)?(\\{(.+?)\\(\\#(.+?)\\)\\})?(\\s+)?(.+)";
            substitution = "$1, $4, $7, $8, $10";
            break;

This outputs a list with all the groups I want and each group separated by a comma. (through the result.split(",");) Now lets say I don't want to use a comma but instead an | or an *. Changing the comma to any other string doesn't seem to change anything. What am I missing?

try (CSVWriter csvWriter = new CSVWriter(new FileWriter(myLocalPath + "CSV/" + choice.toLowerCase() + ".csv")))
{
    Pattern r = Pattern.compile(pattern);

    while (br.readLine() != null)
    {
        String nextLine = br.readLine();

        Matcher matcher = r.matcher(nextLine);

        String result = matcher.replaceAll(substitution);

        String[] line = result.split("lorem");

        csvWriter.writeNext(line, false);
    }
}catch(Exception e){
    System.out.println(e);
    System.out.println("Parsing done!");
}

Try escaping `\\|` and `\\*` because both are meta-characters in regex. — Rahul, Jan 19 '18 at 13:01
Escaping the character didnt work (java should escape characters immediately regardless if it detects its regex right?) — Marco Geertsma, Jan 19 '18 at 13:09
Does your input consistently have that pattern ? Your provided input as `lorem`. What exactly is your input ? Also check [this](https://stackoverflow.com/questions/14134558/list-of-all-special-characters-that-need-to-be-escaped-in-a-regex) answer. — Rahul, Jan 19 '18 at 13:10
Yes the list you see in the regex link is a short part of the input file — Marco Geertsma, Jan 19 '18 at 13:35

score 0 · Answer 1 · edited Jan 19 '18 at 13:32

0

seems what you're missing is Pattern.quote, if argument must be read literally, indeed split argument is a regex.

String[] line = result.split(Pattern.quote("..."));

edited Jan 19 '18 at 13:32

Valentin Michalak

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answered Jan 19 '18 at 13:29

Nahuel Fouilleul

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Cool, i didnt know about the Pattern.quote part. Really neat to know however i dont think this is usefull for my application since my regex statement already performed as it should. Im already getting the results i want and in the groups i want. I just want to change the comma that gets added between each seperator to any other character. Still gonna look more at Pattern.quote though! – Marco Geertsma Jan 19 '18 at 13:40
about the choice of separator, in a csv it is generally `,` or `;` however if this caracter can appear in a field it must be escaped, commonly within enclosing quotes, it may be changed in CSVWriter settings – Nahuel Fouilleul Jan 19 '18 at 13:44

Result separation with regex

1 Answers1