Java help

import java.util.*;
import java.io.*;
public class Reversor {

    private ArrayList<String> sentence;
    private ArrayList<String> newSentence;
    String word;
    String w;

    public void getSentence() throws IOException {
       sentence = new ArrayList<String>();
        Scanner fileScan = new Scanner (new File("data/sentence.txt"));
           while(fileScan.hasNext()){
            String word= fileScan.next();
            sentence.add(word);
            }
           System.out.println(sentence);
       }

    public void reverseEachWord(){
        newSentence = new ArrayList<String>();
        for (String word : sentence) {
            Stack reverseWordStack = stackChars(word);
            String reverseWord = unStackChars(reverseWordStack);
            newSentence.add(reverseWord);
            System.out.println(newSentence);
        }
    }
private Stack<Character> stackChars(String word){

        Stack reverseWordStack = new Stack<Character>();
        for (int i=0; i<word.length(); i++){
            reverseWordStack.push(word.charAt(i));

        }
         return reverseWordStack;
    }

    private String unStackChars(Stack<Character> chars) {
        String newWord = new String();
        while (!chars.isEmpty()) {

            newWord += chars.pop();
        }
        return newWord;
    }

    public String toString() {
        StringBuffer result = new StringBuffer(" ");
        for (String word : newSentence){
            result.append(" ");
            result.append(word);
        }
        return result.toString();
    }
}

import java.io.IOException;
public class Driver {
    public static void main(String[] args){
        Reversor r= new Reversor();
        try {
            r.getSentence();
            r.reverseEachWord();
//            r.stackChars();
            r.toString();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}