如何使用多个分隔符拆分多行？

Question

I have a.txt file with multiple lines with many emails such as Mike@sport.member.com, Laura@music.member.com, Quinn@music.member.com . How do I split them so I can add them to seperate arraylists like music or sport ?

Mike: sport
Laura: music
Quinn: music

Thanks so much.

Answer 1

you can use regex

    Pattern pattern = Pattern.compile("(\\w+)@(\\w+).(\\w+).(\\w+)");
    Matcher matcher = pattern.matcher("Laura@music.member.com");

    if (matcher.find()) {
        matcher.group(1); //this return the name
        matcher.group(2); //this return music sport
        matcher.group(3); // get the company name
        matcher.group(4); // get the domain com in this case
    }

use this to fill the arraylist as you like and have a nice day:)

Answer 2

If you don't mind using ArrayUtils you can use this code:

    String[] emails = new String[] {"Mike@sport.member.com", "Laura@music.member.com", "Quinn@music.member.com"};

    int startLength;
    String[][] split = new String[emails.length][];

    for(int i = 0; i < emails.length; i++) {
        split[i] = emails[i].split("@"); //split by @
        startLength = split[i].length;
        for(int j = 0; j < startLength; j++) {
            split[i] = ArrayUtils.addAll(split[i], split[i][0].split("\\.")); //Split by . and add items to the end of the array
            split[i] = ArrayUtils.remove(split[i], 0); //remove the first item of the array
        }
    }

    System.out.println(Arrays.deepToString(split));

Output:

[[Mike, sport, member, com], [Laura, music, member, com], [Quinn, music, member, com]]

What this does is it uses.split("@") to split the emails into arrays separated by "@" Then goes through for array and splits each item in the array with.split(".").

As it splits the elements the second time it adds them to the end of the split array and removes the first item (which was the item that it just split up).

Note that I had to make the startLength variable to keep track of the original size of the split array because in the second loop its constantly changing length.

This gives you a 2D array with all the items but I won't blame you for no using this because its a bit of a mess.

Answer 3

There are two steps to solve this problem.

1. Read lines from file(a.txt).

    public List<String> readFile() throws IOException {
        String fileName = "/Users/folder/a.txt"; 
        FileInputStream inputStream = new FileInputStream(fileName);
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));

        String str = null;
        List<String> list = new ArrayList<>();
        while ((str = bufferedReader.readLine()) != null) {
            list.add(str);
        }
        //close
        inputStream.close();
        bufferedReader.close();
        return list;
    }

2. Split line, take out data.

    List<String> lines = readFile();
    Pattern pattern = Pattern.compile("([a-zA-Z]+)@([a-zA-Z]+)");
    for (String line : lines) {
        Matcher matcher = pattern.matcher(line);
        if (matcher.find()){
            System.out.println(matcher.group(1) + ":" + matcher.group(2));
        }
    }
    

The result is

Mike:sport
Laura:music
Quinn:music