1    /* 
2    * This program features an ArrayList to do its reverse copy thing from one file to another 
3     */
4    
5    package arraylistplay;
6    
7    import java.io.File;
8    import java.io.FileNotFoundException;
9    import java.io.IOException;
10   import java.io.PrintWriter;
11   import java.util.ArrayList;
12   import  java.util.Scanner;
13   
14   public class ReverseCopy {
15   
16       public static void main (String [] args ) throws FileNotFoundException, IOException {
17           String inputFileName = "AllForUs.text";
18           String outputFileName = "AllForUsReversed.text";
19           ArrayList<String> words = readWordsFromFile(inputFileName);
20           writeWordsToFile(words, outputFileName);
21       }
22   
23       private static ArrayList<String> readWordsFromFile(String inputFileName)
24           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               words.add(word);
32           }
33           // return the words
34           return words;
35       }
36   
37       private static void writeWordsToFile(ArrayList<String> words, String outputFileName)
38           throws IOException {
39           // equate a printer with an output file
40           PrintWriter printer = getPrintWriter(outputFileName);
41           // print the words to the file
42           for (int x = words.size() -1; x>=0; x=x -1){
43               printer.println(words.get(x));
44           }
45           printer.close();
46       }
47   
48       private static Scanner establishScanner(String inputFileName)
49           throws FileNotFoundException{
50           String fullFileName = createFullFileName(inputFileName);
51           return new Scanner(new File(fullFileName));
52       }
53   
54       private static PrintWriter getPrintWriter(String outputFileName)
55           throws FileNotFoundException {
56           String fullFileName = createFullFileName(outputFileName);
57           PrintWriter printer = new PrintWriter(fullFileName);
58   return printer;
59   }
60   
61   // create the full file name for a simple file name, assuming that it will be found in the CS1Files/data subdirectory of the users home directory
62   private static String createFullFileName(String fileName) {
63   String seperator = System.getProperty("file.separtor");
64   String home = System.getProperty("user.home");
65   String path = home + seperator + "CS1Files" + seperator + "data" + seperator;
66   String fullFileName = path + fileName;
67   return fullFileName;
68   }
69   }