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Java Local Development Environments Advanced Tooling Finishing TreeStory

Daniel Paradiso
PLUS
Daniel Paradiso
Courses Plus Student 3,915 Points

This error is killing me. nullPointerException

I have tried my way, no dice... I've ripped others, no dice. What am I doing wrong?

com/teamtreehouse/Main.java
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);
        prompter.run(tmpl);
    }
}
com/teamtreehouse/Prompter.java
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));
        loadCensoredWords();
    }

    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");
            e.printStackTrace();
        }
        mCensoredWords.addAll(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");
            e.printStackTrace();
            System.exit(0);
        }
        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);
            words.add(word);
        }
        return words;
    }

    public String promptForWord(String phrase) throws IOException {
        String newWord = "";
        while (newWord.isEmpty() ||  (mCensoredWords.contains(newWord.toLowerCase().trim()))) {
            if (newWord.isEmpty()) {
                System.out.printf("Please enter your word for %s: %n", phrase);
                newWord = mReader.readLine();
            }

            if (newWord != null && mCensoredWords.contains(newWord.toLowerCase().trim())) {
                System.out.printf("Be nice, please try another word for %s. %n", phrase);
                newWord = mReader.readLine();
            }
        }
        return newWord.trim();
    }
}
pseudo-tests.md
#  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

2 Answers

Simon Coates
Simon Coates
28,692 Points

Try the following. It's from here

package com.teamtreehouse;

import java.util.Arrays;
import java.util.List;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
public class Main {
public static void main(String[] args) {
        BufferedReader mReader = new BufferedReader(new InputStreamReader(System.in));
        System.out.println("Make a story! Write a fill in the blank story with an underscore on each side of the variable like _noun/adjective/etc_");
        Prompter prompter = new Prompter();
        String story = null;
        try {
            story = prompter.promptForStory();
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
        Template tmpl = new Template(story);
        prompter.run(tmpl);
    }
}
package com.teamtreehouse;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
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));
        loadCensoredWords();
    }

    public String promptForStory() throws IOException {
        return mReader.readLine();
    }

    private void loadCensoredWords() {
        mCensoredWords = new HashSet<>();
        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");
            e.printStackTrace();
        }
        mCensoredWords.addAll(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");
            e.printStackTrace();
            System.exit(0);
        }
        // Print out the results that were gathered here by rendering the template
        System.out.println(tmpl.render(results));
    }


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


    public String promptForWord(String phrase) throws IOException {
        System.out.printf("Please enter your word for %s: %n", phrase);
        String entryWord = mReader.readLine();

        while (entryWord!=null && mCensoredWords.contains(entryWord.toLowerCase().trim())) {
            System.out.printf("Be nice, please try another word for %s. %n", phrase);
            entryWord = mReader.readLine();

        }

        return (entryWord==null)? entryWord: entryWord.trim();
    }
}
Simon Coates
Simon Coates
28,692 Points

I just used it to past the test. It has some oddities. That return (entryWord==null)? entryWord: entryWord.trim(); differs from the original code. I was getting some strange behaviours with nulls. But when i retried it, Kevin Faust's code didn't need it. he had something like return entryWord.trim();