1    /* 
2     * The porgram 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       public static void main(String[] args) throws FileNotFoundException, IOException {
17           String inputFileName = "KnowingMe.text";
18           String outputFileName = "KnowingMeReversed.text";
19           ArrayList<String> words = readWordsFromFile(inputFileName);
20           writeWordsToFile(words, outputFileName);
21       }
22   
23       private static ArrayList<String> readWordsFromFile(String inputFileName) throws FileNotFoundException {
24           // Equate a scanner with the input file
25           Scanner scanner = establishScanner(inputFileName);
26           // Read the words from the file intoa dynamically growing ArrayList
27           ArrayList<String> words = new ArrayList<>();
28           while ( scanner.hasNext() ) {
29               String word = scanner.next();
30               words.add(word);
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 = getPrintWriter(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 getPrintWriter(String outputFileName) throws FileNotFoundException {
52           String fullFileName = createFullFileName(outputFileName);
53           PrintWriter printer = new PrintWriter(fullFileName);
54           return printer;
55       }
56   
57   
58       // Create the full file name for a simple file name, assuming that it will be
59       // found in the CS1Files/data subdirectory of the user's home directory.
60   
61       private static String createFullFileName(String fileName) {
62           String separator = System.getProperty("file.separator");
63           String home = System.getProperty("user.home");
64           String path = home + separator + "CS1Files" + separator + "data" + separator;
65           String fullFileName = path + fileName;
66           return fullFileName;
67       }
68   }
69