再帰的な文字列の検索と置換？

Question

私の質問は、テキストファイル内の文字列を見つけて置き換えることです。 このプログラムはA Christmas Carolテキストファイル内の単語ghostのインスタンスを検索し、GhostとGHOSTためBUNNYためghostためbunny、Bunnyでそれらを交換することになっています。小文字のゴーストで動作し、GHOSTのインスタンスはありませんが、大文字のGhostだけでは動作しません。 私の問題は、最後の2つの方法の中にあることを知っています。私は間違って何をしていますか？あなたのsubstitute方法のif声明で

package findandreplace; 

    import java.io.File; 
    import java.io.FileNotFoundException; 
    import java.io.PrintWriter; 
    import java.util.ArrayList; 
    import java.util.Scanner; 


    public class FindAndReplace { 


    public static void main(String[] args) { 
     String filename = "24022-0.txt"; //Charles Dickens - A Christmas Carol 
     try { 
      Scanner fin = getScannerFromFile(filename); 
      String [] story = readFile(fin); 
      String [] newStory = new String[story.length]; 

      for (int i = 0; i < story.length; i++) { 
       newStory[i] = substitute(story[i], "ghost", "bunny"); 
      } 

      if (writeFile("bunny.txt", newStory)) 
       System.out.println("New file successfully created."); 

     } catch (FileNotFoundException e) { 
      System.out.println("File not found"); 
      System.exit(1); 
     } 
    } 

    private static Scanner getScannerFromFile(String filename) throws FileNotFoundException { 
     File f = new File(filename); 
     return new Scanner(f); 
    } 



    private static String [] readFile(Scanner fin) { 
     ArrayList<String> lines = new ArrayList<>(); 
     while (fin.hasNext()) { 
      lines.add(fin.nextLine()); 
     } 
     return lines.toArray(new String[0]); 
    } 


    private static boolean writeFile(String newfile, String [] lines) { 
     File file = new File(newfile); 
     if (file.exists()) { 
      System.out.println("File already exists"); 
     } 
     try { 
      PrintWriter fout = new PrintWriter(file); 
      for (String line : lines) { 
       fout.println(line); 
      } 
      fout.close(); 
     } catch (FileNotFoundException ex) { 
      System.err.println("File error."); 
      return false; 
     } 
     return true; 
    } 

    /** 
    * This method should examine the first word, and return the second word matching case. 
    * For example, if first word is "GHOST", and second word is "bunny", the return value 
    * should be "BUNNY". 
    * NOTE: THIS SHOULD *NOT* BE A RECURSIVE FUNCTION 
    * precondition: the first word is all lowercase, Capitalized, or ALL-CAPS 
    * @return second, matching case of first 
    */ 
    private static String matchWordCase(String first, String second) { 
     if (first.toUpperCase().equals(first)) { 
     second = second.toUpperCase(); 
     } 
     if (first.toLowerCase().equals(first)) { 
      second = second.toLowerCase(); 
     } 
     else if (first.toUpperCase().charAt(0) == first.charAt(0)) { 
      second = second.substring(0, 1).toUpperCase() + second.substring(1); 
     } 
     return second; 
    } 

    /** 
    * This method should return line, with every instance of the word find 
    * should be replaced by replace. There are multiple approaches you can take, 
    * but words should match regardless of case, and case should be preserved. 
    * If you want to assume words are space-separated, you may. However, it is 
    * better if you figure out how to do this otherwise. 
    * NOTE: THIS SHOULD BE A RECURSIVE FUNCTION 
    * @return line - with the appropriate substitutions 
    */ 
    private static String substitute(String line, String find, String replace) { 
     StringBuilder newLine = new StringBuilder(); 
     //TODO: 
     String result; 
     if (line.length() < find.length()) { 
      return line; 
     } 

     if (find.equals(line.substring(0,find.length()))) { 
     line = matchWordCase(find, replace) + 
     substitute(line.substring(find.length()), find, matchWordCase(find, 
     replace)); 
     } else { 
      result = line.charAt(0) + substitute(line.substring(1), find, 
     replace); 
     } 


     return result; 
    } 
} 

Answer 1

、条件がfind.equalsIgnoreCase、代わりのfind.equalsすべきですか？