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Java Local Development Environments Advanced Tooling Finishing TreeStory

Daniel Paradiso
Daniel Paradiso
Courses Plus Student 3,915 Points

Getting a null error.

I'm getting a null error. I have run this code over and over, and it runs all the way through on my end. Posting it here gets errors. What am I doing wrong?

package com.teamtreehouse;

public class Main {

    public static void main(String[] args) {

        Prompter prompter = new Prompter();
        String story = "Thanks __name__ for helping me out.  You are really a __adjective__ __noun__ and I owe you a __noun__.";
        Template tmpl = new Template(story);
package com.teamtreehouse;

import java.io.*;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class Prompter {
    private BufferedReader mReader;
    private Set<String> mCensoredWords;

    public Prompter() {
        mReader = new BufferedReader(new InputStreamReader(System.in));

    private void loadCensoredWords() {
        mCensoredWords = new HashSet<String>();
        Path file = Paths.get("resources", "censored_words.txt");
        List<String> words = null;
        try {
            words = Files.readAllLines(file);
        } catch (IOException e) {
            System.out.println("Couldn't load censored words");

    public void run(Template tmpl) {
        List<String> results = null;
        try {
            results = promptForWords(tmpl);
        } catch (IOException e) {
            System.out.println("There was a problem prompting for words");
        String newStory = tmpl.render(results);
        System.out.printf("Your TreeStory:%n%n%s", newStory);

    public List<String> promptForWords(Template tmpl) throws IOException {
        List<String> words = new ArrayList<String>();
        for (String phrase : tmpl.getPlaceHolders()) {
            String word = promptForWord(phrase);
        return words;

    public String promptForWord(String phrase) throws IOException{

        String newWord = "";
        boolean censored = false;
        while (!censored) {
            censored = true;
            System.out.printf("Choose a word for %s: ", phrase);
            newWord = mReader.readLine().trim();
            if (newWord.isEmpty()) {
                do {
                    System.out.println("You need to enter a word. Try again");
                    System.out.printf("Choose a word for %s: ", phrase);
                    newWord = mReader.readLine().trim();
                } while (newWord.isEmpty());
            for (String word : mCensoredWords) {
                if (word.contentEquals(newWord)) {
                    censored = false;
                    System.out.println("Not an acceptable word. Please try again");
        return newWord;
#  This is essentially what I am testing 
1.  The user is prompted for a new string template (the one with the double underscores in it).

  a. The prompter class has a new method that prompts for the story template, and that method is called.

2.  The user is then prompted for each word that has been double underscored.

   a. The answer is checked to see if it is contained in the censored words.
      User is continually prompted until they enter a valid word

3.  The user is presented with the completed story

1 Answer