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 = "Colors.text";
19           String outputFileName = "ColorsReversed.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 the 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 + "Public_html" + separator + "CS1Files" + separator + "data" + separator;
68           String fullFileName = path + fileName;
69           return fullFileName;
70       }
71   
72   }