Question

I want to implement a program that reads a file (i.e. .txt) and saves the file in an array (I have done this). Then I want to have a 2-dimensional array where I save only the words for every line.

For example if the file contains two lines with two words in every line I want in array[0][0] the first word of the first line and in array[0][1] to have the second word of the first line, etc.

I have the following code:

for (int i=0; i < aryLines.length; i++) {
    String[] channels = aryLines[i].split(" ");

    System.out.println("line " + (i+1) + ": ");

    for (int j=0; j < channels.length; j++){
        System.out.println("word " + (j+1) + ": ");
        System.out.println(channels[j]);
    }

    System.out.println();
}

where the aryLines contatins all the lines but I didn’t find a solution that performs what I described.

Answer 1

Let your 1-D array is: –

String[] lines = new String[10];

You first need to declare an array of array: –

String[][] words = new String[lines.length][];

Then iterate over it, and for each line, split it and assign it to inner array: –

for (int i = 0; i < words.length; i++) {
    words[i] = lines[i].split("\\s+");
}

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Now, the problem will be, not all words are separated by just space. They also have many punctuation that you need to consider. I would leave it to you to split it on all the punctuation.

For e.g.: –

"This line: - has word separated by, : and -"

Now, you would need to find all the punctuation used in your sentence.

---

One thing which you can do is use a Regex to match a pattern for words only, if you are not sure about what all punctuation are used in your line. And add each matched word to an arraylist.

"\\w+"  // this regex will match one or more characters forming words

Let’s see it working in the above example: –

    String str = "This line: - has word separated by, : and -";
    List<String> words = new ArrayList<String>();

    Matcher matcher = Pattern.compile("\\w+").matcher(str);

    while (matcher.find()) {
        words.add(matcher.group());
    }

    System.out.println(words);

OUTPUT : –

[This, line, has, word, separated, by, and]

You can use this approach in your above loop that I posted.