文字列または文字配列のインデックスを取得する最も良い方法は何ですか？

Question

単語内の特定の文字のインデックスを取得する最も良い方法は何ですか。私がこれをやっているのは、私がハングマンのゲームを作って修正しているからです。私はすでにゲームを終えていて、それはうまくいくが、スコアベースのシステムを実装したい。私は、答えが正しいかどうかを調べるためにboolean値をとるkeepScore（）というメソッドを作成しました。それが正しい場合は、見つかった各文字に対して10ポイントを追加します。それが間違っていると、私は10ポイントを差し引います。私のメソッドkeepScore（）は、間違ってどのようなヘルプが実装されていますか？

Hangman.java

import Game.Game; 
import Prompter.Prompter; 

/* This class is the main class that starts the game. 
* It instantiates the Game and Prompter objects. 
*/ 
public class Hangman { 

    public static void main(String[] args) { 
     //Check if an argument has been passed, we expect the answer to be passed 
     if(args.length == 0) { 
      System.out.println("Expected: Java Hangman <answer>"); 
      System.err.println("Answer is required!"); 
      System.exit(1); 
     } 

     System.out.println("Welcome to Hangman!"); 

     //Create an instance of our game 
     Game game = new Game(args[0]); 
     //Create an instance of our prompter 
     Prompter prompter = new Prompter(game); 

     //Starts the game 
     while (game.getRemainingTries() > 0 && !game.isWon()) { 
      prompter.displayProgress(); 
      prompter.promptForGuess(); 
     } 
     //Displays the outcome of the game 
     prompter.displayOutcome(); 
    } 
} 

Game.java

が

package Game; 

/* This class is responsible for implementing the game 
* logic. 
*/ 
public class Game { 
    //Declare our member variables 
    public final static int TOTAL_TRIES = 3; 
    public final static int MAX_SCORE_POINTS = 10; 
    private String mAnswer; 
    private String lettersHit; 
    private String lettersMissed; 
    private int score; 

    //Default constructor 
    public Game(String answer) { 
     //Initialize our member variables 
     mAnswer = answer.toLowerCase(); 
     lettersHit = ""; 
     lettersMissed = ""; 
    } 

    //This method checks to see if the letter was a hit or a miss 
    public boolean checkLetter(char letter){ 
     letter = validateGuess(letter); 
     boolean isHit = mAnswer.indexOf(letter) != -1; 
     //If correct 
     if (isHit) { 
      //Add the letter to the lettersHit pool 
      lettersHit += letter; 
      keepScore(isHit); 
      System.out.println("Hit! Score: " + score); 

     }else { 
      //Add the letter to the lettersMissed pool 
      lettersMissed += letter; 
      keepScore(isHit); 
      System.out.println("Missed! Score: " + score); 
     } 
     return isHit; 
    } 

    private void keepScore(boolean isHit) { 
     if(isHit) { 
      for (int i = 0; i < lettersHit.length(); i++) { 
       score += MAX_SCORE_POINTS; 
      } 
     } else { 
      for (int i = 0; i < lettersMissed.length(); i++) { 
       score -= MAX_SCORE_POINTS; 
      } 
     } 
    } 

    /* 
    This method handles an empty string input. For example, 
    if the user were to press enter on input a 0 length String 
    will cause the program to crash. 
    */ 
    public boolean checkLetter(String letters) { 
     if (letters.length() == 0) { 
      throw new IllegalArgumentException("No letter entered"); 
     } 
     return checkLetter(letters.charAt(0)); 
    } 

    //This method validates the user guess 
    private char validateGuess(char letter) { 
     //If the character is not a letter 
     if (!Character.isLetter(letter)) { 
      //Ask user for a valid letter 
      throw new IllegalArgumentException("A letter is required!"); 
     } 
     //If entry was valid, convert character to lowercase 
     letter = Character.toLowerCase(letter); 

     //Check if the letter has been guessed already 
     if (lettersHit.indexOf(letter) != -1 || lettersMissed.indexOf(letter) != -1) { 
      throw new IllegalArgumentException("The letter " + letter + " has already been guessed"); 
     } 
     return letter; 
    } 

    //This method keeps track of the user's game progress 
    public String getCurrentProgress() { 
     String progress = ""; 
     //For each character in the array of strings of mAnswer 
     for (char letter : mAnswer.toCharArray()) { 
      char display = '-'; 
      if (lettersHit.indexOf(letter) != -1){ 
       display = letter; 
      } 
      progress += display; 
     } 
     return progress; 
    } 

    //Get the current remaining tries 
    public int getRemainingTries() { 
     return TOTAL_TRIES - lettersMissed.length(); 
    } 

    //Get the current answer 
    public String getAnswer() { 
     return mAnswer; 
    } 

    //This method checks if the game is won. 
    public boolean isWon() { 
     return getCurrentProgress().indexOf('-') == -1; 
    } 


    public int getScore(){ 
     return score; 
    } 
} 

Prompter.java

package Prompter; 
import Game.Game; 
import java.util.Scanner; 

/* This class is responsible for displaying instructions and information to the user 
* regarding the game. 
*/ 
public class Prompter { 
    //The game object 
    private Game mGame; 
    private boolean isHit; 
    private boolean acceptable; 

    //Default constructor 
    public Prompter(Game game) { 
     //Get the instance of our game 
     mGame = game; 
     isHit = false; 
     acceptable = false; 
    } 

    //This method prompts the user for a guess 
    public boolean promptForGuess() { 
     //Create an instance of scanner 
     Scanner scanner = new Scanner(System.in); 

     //Loop for input 
     do { 
      System.out.println("Please enter a letter: "); 
      String guess = scanner.nextLine(); 

      try { 
       isHit = mGame.checkLetter(guess); 
       acceptable = true; 
      }catch (IllegalArgumentException iae) { 
       System.out.printf("%s. Please try again!%n", iae.getMessage()); 
      } 
     } while (!acceptable); 
     return isHit; 
    } 

    //This method displays the progress 
    public void displayProgress() { 
     System.out.printf("You have %d tries to guess the answer" + 
       " before you are taken to the gallows. Try to solve: %s%n", mGame.getRemainingTries(), 
       mGame.getCurrentProgress()); 
    } 

    //This method displays the outcome of the game 
    public void displayOutcome() { 
     if(mGame.isWon()) { 
      System.out.printf("Congratulations! you won with %d tries remaining.%n" + 
        "Your total score: %d%n", mGame.getRemainingTries(), mGame.getScore()); 
     }else { 
      System.out.printf("Bummer! The answer was: %s", mGame.getAnswer()); 
     } 
    } 
} 

Answer 1

あなたのこの方法を見てみましょう。

private void keepScore(boolean isHit) { 
    if(isHit) { 
     for (int i = 0; i < lettersHit.length(); i++) { 
      score += MAX_SCORE_POINTS; 
     } 
    } else { 
     for (int i = 0; i < lettersMissed.length(); i++) { 
      score -= MAX_SCORE_POINTS; 
     } 
    } 
} 

MAX_SCORE_POINTS倍の数、良い文字の数がの場合は、と表示されます。これは良い文字の数がlettersHitであるためです。今、lettersHitには何がありますか？あなたが最初から見つけたすべての手紙があります。

だからあなたが持っているでしょう：

word to guess: anaconda 

letter: a 
lettersHit = "a", score += (lettersHit.length * 10) = 10 
letter: c 
lettersHit = "ac", score += (lettersHit.length * 10) = 30 

あなただけので、出現数、スコアを取得するためにStringUtils.countMatches(mAnswer, letter);を使用することができます。