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javafile-ioreplaceallfile.readalllines

Why replaceAll method is not working?


I read from file like this:

List<String> list = Files.readAllLines(Paths.get("file.csv"));

After that I try to call replaceAll method on every string in the list, but it doesn't work with any regex and replacement string. Although, when I apply replaceAll with the same arguments to a string that I assign in code, it works fine. The strings look like this: "Hello","World","!!!"

Edit:

List<String> res = Files.readAllLines(Paths.get("TimeTable.csv"));

String p = "^\"(\\w+) (\\w+) (\\w+) (?:.+)?\",\"(\\d+)\\.(\\d+)\\.(\\d+)\",\"(\\d+):(\\d+):(\\d+)\"(?:.*?)$/i";
String rep = "$6-$5-$4 ==> $7:$8 $1 $2 $3";
String s = res.get(1).replaceAll(p, rep);
System.out.print(s);

The file consists of strings like that:

"AK Pz 310u PI-13-5","23.02.2015","07:45:00","23.02.2015","09:20:00","False","True","23.02.2015","07:40:00","2","Common","AK Pz 310u PI-13-5","Common"

Here is the exact code I'm using: http://pastebin.com/GhhrRWAU

And here is the file I'm trying to parse: http://www.fileconvoy.com/dfl.php?id=g450e5a3e83854bdc999643999f2ceb8c622d6abf2


Solution

  • RegEx is always a headache for me, too. Actually your regex expression is almost correct (you can check it on https://regex101.com/, for example). But this is Java and you should use inline modifier:

    String p = "^\"(\\w+) (\\w+) (\\w+) (?:.+)?\",\"(\\d+)\\.(\\d+)\\.(\\d+)\",\"(\\d+):(\\d+):(\\d+)\"(?:.*?)$";
    String rep = "$6-$5-$4 ==> $7:$8 $1 $2 $3";
    String test = "\"AK Pz 310u PI-13-5\",\"23.02.2015\",\"07:45:00\",\"23.02.2015\",\"09:20:00\",\"False\",\"True\",\"23.02.2015\",\"07:40:00\",\"2\",\"Common\",\"AK Pz 310u PI-13-5\",\"Common\"";
    String s = test.replaceAll(p, rep);
    System.out.print(s);
    

    Output:

    2015-02-23 ==> 07:40 AK Pz 310u
    

    BTW, \i modifier is useless here, because \w already matches [a-zA-Z0-9_]

    EDIT Your file contains non-Latin characters, so you can use Regex groups instead:

    List<String> res = Files.readAllLines(Paths.get("TimeTable.csv"));
    String p = "(?i)^\"([\\p{L}_]+) (\\p{L}+) ([\\p{L}\\p{N}-_]+) (?:.+)?\",\"(\\d+)\\.(\\d+)\\.(\\d+)\",\"(\\d+):(\\d+):(\\d+)\"(?:.*?)$";
    String rep = "$6-$5-$4 ==> $7:$8 $1 $2 $3";
    for (String str : res){
        System.out.println(str.replaceAll(p, rep));
    }