1 /* 2 * Program featuring ArrayLists and file IO to read and reverse copy a lyric. 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 = "Rebel.text"; 18 String outputFileName = "RebelReversed.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 into a 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 // Create the full file name for a simple file name, assuming that it will be found in the CS1Files/data subdirectory of the user's home directory 58 private static String createFullFileName(String fileName) { 59 String separator = System.getProperty(("file.separator")); 60 String home = System.getProperty("user.home"); 61 String path = home + separator + "CS1Files" + separator + "Data" + separator; 62 String fullFileName = path + fileName; 63 return fullFileName; 64 } 65 }