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 = "100Degrees.text";
19           String outputFileName = "100DegreesReversed.text";
20           ArrayList<String> words = readWordsFromFile(inputFileName);
21           writeWordsToFile(words, outputFileName);
22       }
23   
24       private static ArrayList<String> readWordsFromFile(String inputFileName)
25               throws FileNotFoundException{
26           // Equate a scanner with the input file
27           Scanner scanner = establishScanner(inputFileName);
28           // Read words from the file into a dynamically growing ArrayList
29           ArrayList<String> words = new ArrayList<>();
30           while (scanner.hasNext()){
31               String word = scanner.next();
32               words.add(word);
33           }
34           // Return the words
35           return words;
36       }
37   
38       private static void writeWordsToFile(ArrayList<String> words, String outputFileName)
39               throws IOException{
40           // Equate a printer with an output file
41           PrintWriter printer = getPrintWriter(outputFileName);
42           // Print the words to the file
43           for (int x = words.size() - 1;x >= 0;x = x-1){
44               printer.println(words.get(x));
45           }
46           printer.close();
47       }
48   
49       private static Scanner establishScanner(String inputFileName)
50               throws FileNotFoundException {
51           String fullFileName = createFullFileName(inputFileName);
52           return new Scanner(new File(fullFileName));
53       }
54   
55       private static PrintWriter getPrintWriter(String outputFileName)
56               throws FileNotFoundException {
57           String fullFileName = createFullFileName(outputFileName);
58           PrintWriter printer = new PrintWriter(fullFileName);
59           return printer;
60       }
61   
62       // Create the full file name for a simple file name, assuming that it will be
63       // found in the CS1Files/data subdirectory of the user's home directory.
64       private static String createFullFileName(String fileName){
65           String separator = System.getProperty("file.separator");
66           String home = System.getProperty("user.home");
67           String path = home + separator + "CS1Files" + separator + "data" +separator;
68           String fullFileName = path + fileName;
69           return fullFileName;
70       }
71   
72   }
73