import java.util.*;

/**
 * Write a description of class SpellChecker here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
public class SpellChecker
{
    private List<String> words;
    
    /**
     * ...
     */
    public SpellChecker()
    {
        DictReader reader = new DictReader("words.txt");
        words = reader.getWords();
    }

    /**
     * ...
     */
    public ArrayList<String> save()
    {
        
        ArrayList<String> wordList;
        wordList = new ArrayList<String>();
        wordList.addAll(words);
        DictReader.save(wordList);
        
    }


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import java.util.List; import java.util.ArrayList;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;


/**
 * Class DictReader offers functionality to load a dictionary from a file, 
 * and to save it back to a file.
 * 
 * To use this class, create an instance of this class with the file name as 
 * a parameter. Then call 'getDictionary' to receive the dictionary object.
 * 
 * @author M. Kolling
 * @version 2006-10-24, modified by M.E. Caspersen 2007-04-24
 * 
 */
public class DictReader
{
    private List<String> dict;
    private String filename;

    /**
     * Create a DictReader instance from a file.
     */
    public DictReader(String filename)
    {
        loadDictionary(filename);
        this.filename = filename;
    }
    
    /**
     * Return the dictionary as a list of words.
     */
    public List<String> getWords()
    {
        return dict;
    }

    /**
     * Accept a new dictionary and save it under the same name. Use the new
     * one as our dictionary from now on.
     */
    public void save(ArrayList<String> dictionary)
    {
        try {
            FileWriter out = new FileWriter(filename);
            for(String word : dictionary) {
                out.write(word);
                out.write("\n");
            }
            out.close();
            dict = dictionary;
        }
        catch(IOException exc) {
            System.out.println("Error writing dictionary file: " + exc);
        }
    }

    /**
     * Load the dictionary from disk and store it in the 'dict' field.
     */
    private void loadDictionary(String filename)
    {
        dict = new ArrayList<String>();
        
        try {
            BufferedReader in = new BufferedReader(new FileReader(filename));
            String word = in.readLine();
            while(word != null) {
                dict.add(word);
                word = in.readLine();
            }
            in.close();
        }
        catch(IOException exc) {
            System.out.println("Error reading dictionary file: " + exc);
        }
    }
}