1 /* 2 *THis program features an ArrayList to do its reverse copy thing 3 * from one file to another. 4 */ 5 6 package arraylistplay; 7 8 import java.io.File; 9 import java.io.FileNotFoundException; 10 import java.io.IOException; 11 import java.io.PrintWriter; 12 import java.util.ArrayList; 13 import java.util.Scanner; 14 15 public class ReverseCopy { 16 17 public static void main(String[] args) throws FileNotFoundException, IOException { 18 String inputFileName = "WhatsFree.text"; 19 String outputFileName = "WhatsFreeReversed.text"; 20 ArrayList<String> words = readWordsFromFile(inputFileName); 21 writeWordsToFile(words, outputFileName); 22 } 23 24 private static ArrayList<String> readWordsFromFile(String inputFileName) throws FileNotFoundException { 25 // Equate a scanner with the input file 26 Scanner scanner = establishScanner(inputFileName); 27 // Read the words from the file into a dynamically growing ArrayList 28 ArrayList<String> words = new ArrayList<>(); 29 while (scanner.hasNext()) { 30 String word = scanner.next(); 31 } 32 //return the words 33 return words; 34 } 35 36 private static void writeWordsToFile(ArrayList<String> words, String outputFileName) throws IOException { 37 //Equate a printer with an output file 38 PrintWriter printer = getPrinterWriter(outputFileName); 39 //Print the words to the file 40 for (int x = words.size() - 1; x >= 0; x = x - 1) { 41 printer.println(words.get(x)); 42 } 43 printer.close(); 44 } 45 46 private static Scanner establishScanner(String inputFileName) throws FileNotFoundException { 47 String fullFileName = createFullFileName(inputFileName); 48 return new Scanner(new File(fullFileName)); 49 } 50 51 private static PrintWriter getPrinterWriter(String outputFileName) throws FileNotFoundException { 52 String fullFileName = createFullFileName(outputFileName); 53 PrintWriter printer = new PrintWriter(fullFileName); 54 return printer; 55 } 56 57 //Create the full file name for a simple file name, assuming that it will be 58 //found in the CS1Files/data subdirectory of the user's home directory. 59 private static String createFullFileName(String fileName) { 60 String separator = System.getProperty("file.separator"); 61 String home = System.getProperty("user.home"); 62 String path = home + separator + "CS1Files" + separator + "data" + separator; 63 String fullFileName = path + fileName; 64 return fullFileName; 65 } 66 } 67 68