Provided Code

// Part A: write entire RandomStringChooser class
// Part B: given skeleton:
public class RandomLetterChooser extends RandomStringChooser
{
    public RandomLetterChooser(String str)
    { /* to be implemented in part (b) */ }

    public static String[] getSingleLetters(String str)
    { /* provided — splits str into array of 1-char strings */ }
}

Part A — RandomStringChooser class (7 Points)

Write the entire RandomStringChooser class: constructor takes a String array and populates an ArrayList; getNext() picks and removes a random element, returning 'NONE' if empty.

Check Answer Clear

public class RandomStringChooser
{
    private ArrayList words;

    public RandomStringChooser(String[] wordArray)
    {
        words = new ArrayList();
        for (String w : wordArray)
        {
            words.add(w);
        }
    }

    public String getNext()
    {
        if (words.isEmpty())
            return "NONE";

        int index = (int)(Math.random() * words.size());
        return words.remove(index);
    }
}

Part B — RandomLetterChooser subclass (2 Points)

Write the RandomLetterChooser constructor. It receives a String of letters and must call the parent constructor with getSingleLetters(str).

Check Answer Clear

public RandomLetterChooser(String str)
{
    super(getSingleLetters(str));
}

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