// CSE 143, Summer 2012
// Code written in lecture to reverse a file. 
// The two versions of the code we wrote have been factored into 
// methods so that you can view both.  

import java.util.*;
import java.io.*;

public class ReverseFile {

	public static void main (String[] args) throws FileNotFoundException{
		reverseUsingAnArray();
		System.out.println();
		reverseUsingAnArrayList();
	}
	
	// initial code using our 142 knowledge
	public static void reverseUsingAnArray() throws FileNotFoundException{
		// hardcoding 1000 as the array size is bad! 
		// the file we are reading could be longer or shorter
		String[] allWords = new String[1000];
		int wordCount = 0;
		Scanner input = new Scanner(new File("poem.txt"));

		while(input.hasNext()) {
			allWords[wordCount] = input.next();
			wordCount++;
		}
		
		// we have to start at wordCount NOT at allWords.length
		// as there may be extra space in the array if it is longer
		// than our file
		for (int i = wordCount - 1; i >= 0; i--) {
			System.out.print(allWords[i] + " ");
		}

	}
	
	// improved code transitioned to use an ArrayList
	public static void reverseUsingAnArrayList() throws FileNotFoundException{
		ArrayList<String> allWords = new ArrayList<String>();
		Scanner input = new Scanner(new File("poem.txt"));

		while(input.hasNext()) {
			allWords.add(input.next());
		}
		
		for (int i = allWords.size() -1; i >= 0; i--) {
			System.out.print(allWords.get(i) + " ");
		}
	}

}