6日でできる 新Java入門｜改良4：クイズゲームをGUIにする

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class QuizGame extends JFrame {
    private boolean cheatMode;

    private CardLayout cardLayout;
    private JPanel mainPanel;

    private JComboBox<QuizGenre> genreComboBox;
    private JLabel quizTitleLabel;
    private JLabel questionCountLabel;
    private JLabel questionLabel;
    private JLabel resultMessageLabel;
    private JLabel scoreLabel;
    private JButton[] choiceButtons;

    private QuizManager manager;
    private QuizManager.QuizQuestion currentQuestion;

    public QuizGame(boolean cheatMode) {
        this.cheatMode = cheatMode;

        setTitle("アニメクイズゲーム");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(760, 520);
        setLocationRelativeTo(null);

        cardLayout = new CardLayout();
        mainPanel = new JPanel(cardLayout);

        mainPanel.add(createTitlePanel(), "TITLE");
        mainPanel.add(createQuizPanel(), "QUIZ");
        mainPanel.add(createResultPanel(), "RESULT");

        add(mainPanel);
        showTitle();
    }

    private JPanel createTitlePanel() {
        JPanel panel = new JPanel(new BorderLayout());
        panel.setBackground(new Color(235, 245, 255));

        JLabel titleLabel = new JLabel("アニメクイズゲーム", SwingConstants.CENTER);
        titleLabel.setFont(new Font("Meiryo", Font.BOLD, 38));
        titleLabel.setBorder(BorderFactory.createEmptyBorder(50, 10, 20, 10));

        JLabel descriptionLabel = new JLabel("ジャンルを選んで「スタート」を押してください", SwingConstants.CENTER);
        descriptionLabel.setFont(new Font("Meiryo", Font.PLAIN, 18));

        genreComboBox = new JComboBox<QuizGenre>(QuizGenre.values());
        genreComboBox.setFont(new Font("Meiryo", Font.PLAIN, 18));
        genreComboBox.setPreferredSize(new Dimension(420, 40));

        JButton startButton = new JButton("スタート");
        startButton.setFont(new Font("Meiryo", Font.BOLD, 22));
        startButton.setPreferredSize(new Dimension(180, 50));

        startButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                startGame();
            }
        });

        JPanel centerPanel = new JPanel();
        centerPanel.setOpaque(false);
        centerPanel.setLayout(new BoxLayout(centerPanel, BoxLayout.Y_AXIS));

        JPanel comboPanel = new JPanel();
        comboPanel.setOpaque(false);
        comboPanel.add(genreComboBox);

        JPanel buttonPanel = new JPanel();
        buttonPanel.setOpaque(false);
        buttonPanel.add(startButton);

        centerPanel.add(descriptionLabel);
        centerPanel.add(Box.createVerticalStrut(25));
        centerPanel.add(comboPanel);
        centerPanel.add(Box.createVerticalStrut(25));
        centerPanel.add(buttonPanel);

        panel.add(titleLabel, BorderLayout.NORTH);
        panel.add(centerPanel, BorderLayout.CENTER);

        return panel;
    }

    private JPanel createQuizPanel() {
        JPanel panel = new JPanel(new BorderLayout());
        panel.setBackground(Color.WHITE);

        quizTitleLabel = new JLabel("", SwingConstants.CENTER);
        quizTitleLabel.setFont(new Font("Meiryo", Font.BOLD, 24));
        quizTitleLabel.setBorder(BorderFactory.createEmptyBorder(20, 10, 5, 10));

        questionCountLabel = new JLabel("", SwingConstants.CENTER);
        questionCountLabel.setFont(new Font("Meiryo", Font.PLAIN, 16));

        questionLabel = new JLabel("", SwingConstants.CENTER);
        questionLabel.setFont(new Font("Meiryo", Font.BOLD, 24));
        questionLabel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));

        resultMessageLabel = new JLabel(" ", SwingConstants.CENTER);
        resultMessageLabel.setFont(new Font("Meiryo", Font.BOLD, 18));
        resultMessageLabel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));

        JPanel topPanel = new JPanel(new GridLayout(2, 1));
        topPanel.setOpaque(false);
        topPanel.add(quizTitleLabel);
        topPanel.add(questionCountLabel);

        JPanel choicePanel = new JPanel(new GridLayout(4, 1, 10, 10));
        choicePanel.setBackground(Color.WHITE);
        choicePanel.setBorder(BorderFactory.createEmptyBorder(10, 90, 10, 90));

        choiceButtons = new JButton[4];
        for (int i = 0; i < choiceButtons.length; i++) {
            final int index = i;
            choiceButtons[i] = new JButton();
            choiceButtons[i].setFont(new Font("Meiryo", Font.PLAIN, 18));
            choiceButtons[i].setFocusPainted(false);
            choiceButtons[i].addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e) {
                    checkAnswer(index);
                }
            });
            choicePanel.add(choiceButtons[i]);
        }

        JPanel centerPanel = new JPanel(new BorderLayout());
        centerPanel.setOpaque(false);
        centerPanel.add(questionLabel, BorderLayout.NORTH);
        centerPanel.add(choicePanel, BorderLayout.CENTER);
        centerPanel.add(resultMessageLabel, BorderLayout.SOUTH);

        panel.add(topPanel, BorderLayout.NORTH);
        panel.add(centerPanel, BorderLayout.CENTER);

        return panel;
    }

    private JPanel createResultPanel() {
        JPanel panel = new JPanel(new BorderLayout());
        panel.setBackground(new Color(245, 250, 255));

        JLabel titleLabel = new JLabel("ゲーム終了", SwingConstants.CENTER);
        titleLabel.setFont(new Font("Meiryo", Font.BOLD, 36));
        titleLabel.setBorder(BorderFactory.createEmptyBorder(60, 10, 20, 10));

        scoreLabel = new JLabel("", SwingConstants.CENTER);
        scoreLabel.setFont(new Font("Meiryo", Font.BOLD, 26));

        JButton titleButton = new JButton("タイトルへ");
        titleButton.setFont(new Font("Meiryo", Font.BOLD, 22));
        titleButton.setPreferredSize(new Dimension(200, 55));
        titleButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                showTitle();
            }
        });

        JPanel buttonPanel = new JPanel();
        buttonPanel.setOpaque(false);
        buttonPanel.add(titleButton);

        panel.add(titleLabel, BorderLayout.NORTH);
        panel.add(scoreLabel, BorderLayout.CENTER);
        panel.add(buttonPanel, BorderLayout.SOUTH);

        return panel;
    }

    private void startGame() {
        try {
            QuizGenre quizGenre = (QuizGenre) genreComboBox.getSelectedItem();

            manager = new QuizManager(
                quizGenre.getFileName(),
                quizGenre.getTitle(),
                quizGenre.getQuestionCount(),
                cheatMode
            );

            manager.startQuiz();
            quizTitleLabel.setText(quizGenre.getTitle());
            showNextQuestion();
            cardLayout.show(mainPanel, "QUIZ");

        } catch (Exception e) {
            JOptionPane.showMessageDialog(
                this,
                "問題データの読み込みに失敗しました。\n" + e.getMessage(),
                "エラー",
                JOptionPane.ERROR_MESSAGE
            );
        }
    }

    private void showNextQuestion() {
        currentQuestion = manager.nextQuestion();

        if (currentQuestion == null) {
            showResult();
            return;
        }

        questionCountLabel.setText(currentQuestion.getNumber() + "問目 / " + manager.getQuestionCount() + "問");
        questionLabel.setText("<html><div style='text-align:center;'>「" + currentQuestion.getQuestionText() + "」</div></html>");
        resultMessageLabel.setText(" ");

        for (int i = 0; i < choiceButtons.length; i++) {
            choiceButtons[i].setEnabled(true);
            choiceButtons[i].setText((i + 1) + "：" + currentQuestion.getChoice(i));
        }

        if (manager.isCheatMode()) {
            resultMessageLabel.setText("【チートモード】正解は「" + currentQuestion.getCorrectAnswer() + "」です。");
        }
    }

    private void checkAnswer(int selectedIndex) {
        boolean correct = manager.checkAnswer(currentQuestion, selectedIndex);

        for (int i = 0; i < choiceButtons.length; i++) {
            choiceButtons[i].setEnabled(false);
        }

        if (correct) {
            resultMessageLabel.setText("正解です！");
        } else {
            resultMessageLabel.setText("不正解。正解は「" + currentQuestion.getCorrectAnswer() + "」です。");
        }

        Timer timer = new Timer(1200, new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                showNextQuestion();
            }
        });
        timer.setRepeats(false);
        timer.start();
    }

    private void showResult() {
        scoreLabel.setText(
            "<html><div style='text-align:center;'>全" + manager.getQuestionCount()
            + "問終了！<br>あなたの得点は " + manager.getScore() + " 点です。</div></html>"
        );
        cardLayout.show(mainPanel, "RESULT");
    }

    private void showTitle() {
        cardLayout.show(mainPanel, "TITLE");
    }

    public static void main(String[] args) {
        final boolean cheatMode = (args.length > 0 && args[0].equals("cheat"));

        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new QuizGame(cheatMode).setVisible(true);
            }
        });
    }
}

public enum QuizGenre {
    DRAGONBALL(1, "dragonball_quiz.txt", "ドラゴンボール・クイズ", 10),
    KIMETSU(2, "kimetsu_quiz.txt", "鬼滅の刃・クイズ", 10),
    JOJO(3, "jojo_quiz.txt", "ジョジョの奇妙な冒険・クイズ", 10);

    private int code;
    private String fileName;
    private String title;
    private int questionCount;

    QuizGenre(int code, String fileName, String title, int questionCount) {
        this.code = code;
        this.fileName = fileName;
        this.title = title;
        this.questionCount = questionCount;
    }

    public int getCode() {
        return code;
    }

    public String getFileName() {
        return fileName;
    }

    public String getTitle() {
        return title;
    }

    public int getQuestionCount() {
        return questionCount;
    }

    public static QuizGenre fromInt(int code) {
        for (QuizGenre g : QuizGenre.values()) {
            if (g.code == code) {
                return g;
            }
        }
        return DRAGONBALL;
    }

    public String toString() {
        return title;
    }
}

public String toString() {
    return title;
}

import java.io.BufferedReader;
import java.io.FileReader;
import java.util.ArrayList;
import java.util.Random;

public class QuizManager {
    private String fileName;
    private String title;
    private int questionCount;
    private boolean cheatMode;

    private ArrayList<String> questions = new ArrayList<String>();
    private ArrayList<String> answers = new ArrayList<String>();

    private ArrayList<String> quizQuestions;
    private ArrayList<String> quizAnswers;

    private int score;
    private int currentNumber;
    private Random rand = new Random();

    public QuizManager(String fileName, String title, int questionCount, boolean cheatMode) throws Exception {
        this.fileName = fileName;
        this.title = title;
        this.questionCount = questionCount;
        this.cheatMode = cheatMode;
        loadQuestions();
    }

    private void loadQuestions() throws Exception {
        BufferedReader br = new BufferedReader(new FileReader(fileName));
        String line;

        while ((line = br.readLine()) != null) {
            int idx = line.indexOf(',');

            if (idx == -1) {
                continue;
            }

            questions.add(line.substring(0, idx));
            answers.add(line.substring(idx + 1));
        }

        br.close();
    }

    public void startQuiz() {
        score = 0;
        currentNumber = 0;

        quizQuestions = new ArrayList<String>(questions);
        quizAnswers = new ArrayList<String>(answers);
    }

    public QuizQuestion nextQuestion() {
        if (currentNumber >= questionCount || quizQuestions.size() == 0) {
            return null;
        }

        int qIdx = rand.nextInt(quizQuestions.size());
        String questionText = quizQuestions.remove(qIdx);
        String correctAnswer = quizAnswers.remove(qIdx);

        ArrayList<String> choices = new ArrayList<String>();
        ArrayList<String> backupAnswers = new ArrayList<String>(quizAnswers);

        for (int j = 0; j < 3 && backupAnswers.size() > 0; j++) {
            int cIdx = rand.nextInt(backupAnswers.size());
            choices.add(backupAnswers.remove(cIdx));
        }

        int insertIdx = rand.nextInt(choices.size() + 1);
        choices.add(insertIdx, correctAnswer);

        currentNumber++;

        return new QuizQuestion(
            currentNumber,
            title,
            questionText,
            correctAnswer,
            choices,
            insertIdx
        );
    }

    public boolean checkAnswer(QuizQuestion question, int selectedIndex) {
        boolean correct = (selectedIndex == question.getCorrectIndex());

        if (correct) {
            score++;
        }

        return correct;
    }

    public int getScore() {
        return score;
    }

    public int getQuestionCount() {
        return questionCount;
    }

    public boolean isCheatMode() {
        return cheatMode;
    }

    public static class QuizQuestion {
        private int number;
        private String title;
        private String questionText;
        private String correctAnswer;
        private ArrayList<String> choices;
        private int correctIndex;

        public QuizQuestion(
            int number,
            String title,
            String questionText,
            String correctAnswer,
            ArrayList<String> choices,
            int correctIndex
        ) {
            this.number = number;
            this.title = title;
            this.questionText = questionText;
            this.correctAnswer = correctAnswer;
            this.choices = choices;
            this.correctIndex = correctIndex;
        }

        public int getNumber() {
            return number;
        }

        public String getTitle() {
            return title;
        }

        public String getQuestionText() {
            return questionText;
        }

        public String getCorrectAnswer() {
            return correctAnswer;
        }

        public String getChoice(int index) {
            return choices.get(index);
        }

        public int getCorrectIndex() {
            return correctIndex;
        }
    }
}

final boolean cheatMode = (args.length > 0 && args[0].equals("cheat"));

SwingUtilities.invokeLater(new Runnable() {
    public void run() {
        new QuizGame(cheatMode).setVisible(true);
    }
});

mainPanel.add(createTitlePanel(), "TITLE");
mainPanel.add(createQuizPanel(), "QUIZ");
mainPanel.add(createResultPanel(), "RESULT");

startButton.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        startGame();
    }
});

QuizGenre quizGenre = (QuizGenre) genreComboBox.getSelectedItem();

manager = new QuizManager(
    quizGenre.getFileName(),
    quizGenre.getTitle(),
    quizGenre.getQuestionCount(),
    cheatMode
);

manager.startQuiz();
quizTitleLabel.setText(quizGenre.getTitle());
showNextQuestion();
cardLayout.show(mainPanel, "QUIZ");

choiceButtons[i].addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        checkAnswer(index);
    }
});

boolean correct = manager.checkAnswer(currentQuestion, selectedIndex);

Timer timer = new Timer(1200, new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        showNextQuestion();
    }
});
timer.setRepeats(false);
timer.start();

if (currentQuestion == null) {
    showResult();
    return;
}

cardLayout.show(mainPanel, "RESULT");

java QuizGame cheat

if (manager.isCheatMode()) {
    resultMessageLabel.setText("【チートモード】正解は「" + currentQuestion.getCorrectAnswer() + "」です。");
}

java QuizGame

問題文,正解

孫悟空のサイヤ人としての名前,カカロット

Timer timer = new Timer(1200, new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        showNextQuestion();
    }
});

JOptionPane.showMessageDialog(
    this,
    "問題データの読み込みに失敗しました。\n" + e.getMessage(),
    "エラー",
    JOptionPane.ERROR_MESSAGE
);

java QuizGame

java QuizGame cheat