Question

This is the below text file(log.txt) I am opening and need to match each line using regular expressions.

Jerty|gas|petrol|2.42 
Tree|planet|cigar|19.00
Karie|entertainment|grocery|9.20

So I wrote this regular expressions but it is not getting matched.

public static String pattern = "(.*?)|(.*?)|(.*?)|(.*?)";
    public static void main(String[] args) {
        File file = new File("C:\\log.txt");
        try {
            Pattern regex = Pattern.compile(pattern);
            Scanner scanner = new Scanner(file);
            while (scanner.hasNextLine()) {
                String line = scanner.nextLine();
                Matcher m = regex.matcher(line);
                if(m.matches()) {
                    System.out.println(m.group(1));
                }

            }
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

Any suggestions will be appreciated.

Answer 1

The | is a special regex symbol which means ‘or’. So, you have to escape it.

public static String pattern = "(.*?)\\|(.*?)\\|(.*?)\\|(.*?)";