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Java Local Development Environments Advanced Tooling Finishing TreeStory

Brian Bartholomew
Brian Bartholomew
1,741 Points

Throwing NullPointerException and I don't know why. It works just fine in my local environment.

It is probably a unit test or something and I don't know how to handle the input. Any insights would be very helpful.

package com.teamtreehouse;

import java.util.Arrays;
import java.util.List;
import java.io.*;

public class Main {

    public static void main(String[] args) {
        BufferedReader mReader = new BufferedReader(new InputStreamReader(System.in));
        Prompter prompter = new Prompter();

        String storyEx = "Thanks __name__ for helping me out.  You are really a __adjective__ __noun__ and I owe you a __noun__.";

        String story = "";
        try {
            do {
                System.out.println("Enter Story");
                System.out.printf("Example: %n%s%n: ", storyEx);
                story = mReader.readLine();
            }while(story == null || story =="");
        } catch (IOException e) {

        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");

     * Prompts user for each of the blanks
     * @param tmpl The compiled template
     * @return
     * @throws IOException
    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;

     * Prompts the user for the answer to the fill in the blank.  Value is guaranteed to be not in the censored words list.
     * @param phrase The word that the user should be prompted.  eg: adjective, proper noun, name
     * @return What the user responded
    public String promptForWord(String phrase) throws IOException {
        String word = "";
            System.out.printf("%s: ", phrase);
            word = mReader.readLine();
//            if (mCensoredWords.contains(word.toLowerCase())) {
//                System.out.println("That is rude!");
//            }
        }while (mCensoredWords.contains(word.toLowerCase()) || word == null || word == "");

        return word;
#  This is essentially what I am testing 
1.  The user is prompted for a string template (the one with the double underscores in it)

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

I had a similar issue. What you need to do is create a new method in the Prompter that actually gets a new template using the mReader, and call that method from the main method of Main.