Question

So I can search for a string in my text file, however, I wanted to sort data within this ArrayList and implement an algorithm. Is it possible to read from a text file and the values [Strings] within the text file be stored in a String[] Array.

Also is it possible to separate the Strings? So instead of my Array having:

[Alice was beginning to get very tired of sitting by her sister on the, bank, and of having nothing to do:]

is it possible to an array as:

["Alice", "was" "beginning" "to" "get"...]

.

    public static void main(String[]args) throws IOException
    {
        Scanner scan = new Scanner(System.in);
        String stringSearch = scan.nextLine();

        BufferedReader reader = new BufferedReader(new FileReader("File1.txt"));
        List<String> words = new ArrayList<String>();

        String line;
        while ((line = reader.readLine()) != null) {                
            words.add(line);
        }

        for(String sLine : words) 
        {
            if (sLine.contains(stringSearch)) 
            {
                int index = words.indexOf(sLine);
                System.out.println("Got a match at line " + index);

            }
         }

        //Collections.sort(words);
        //for (String str: words)
        //      System.out.println(str);

        int size = words.size();
        System.out.println("There are " + size + " Lines of text in this text file.");
        reader.close();

        System.out.println(words);

    }

Answer 1

To split a line into an array of words, use this:

String words = sentence.split("[^\\w']+");

The regex [^\w'] means "not a word char or an apostrophe"

This will capture words with embedded apostrophes like "can’t" and skip over all punctuation.

Edit:

A comment has raised the edge case of parsing a quoted word such as 'this' as this.
Here’s the solution for that – you have to first remove wrapping quotes:

String[] words = input.replaceAll("(^|\\s)'([\\w']+)'(\\s|$)", "$1$2$3").split("[^\\w']+");

Here’s some test code with edge and corner cases:

public static void main(String[] args) throws Exception {
    String input = "'I', ie \"me\", can't extract 'can't' or 'can't'";
    String[] words = input.replaceAll("(^|[^\\w'])'([\\w']+)'([^\\w']|$)", "$1$2$3").split("[^\\w']+");
    System.out.println(Arrays.toString(words));
}

Output:

[I, ie, me, can't, extract, can't, or, can't]