v2.0

pom.xml

@@ -0,0 +1,70 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.example</groupId>
+    <artifactId>math-learning-app</artifactId>
+    <version>1.0.0</version>
+
+    <properties>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    </properties>
+
+    <dependencies>
+        <!-- JavaMail API -->
+        <dependency>
+            <groupId>com.sun.mail</groupId>
+            <artifactId>javax.mail</artifactId>
+            <version>1.6.2</version>
+        </dependency>
+
+        <!-- JAF (Java Activation Framework) -->
+        <dependency>
+            <groupId>javax.activation</groupId>
+            <artifactId>activation</artifactId>
+            <version>1.1.1</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <sourceDirectory>src</sourceDirectory>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
+                <configuration>
+                    <source>11</source>
+                    <target>11</target>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-assembly-plugin</artifactId>
+                <version>3.3.0</version>
+                <configuration>
+                    <archive>
+                        <manifest>
+                            <mainClass>ui.MathLearningApp</mainClass>
+                        </manifest>
+                    </archive>
+                    <descriptorRefs>
+                        <descriptorRef>jar-with-dependencies</descriptorRef>
+                    </descriptorRefs>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>make-assembly</id>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>single</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+</project>

src/model/GradeType.java

@@ -0,0 +1,22 @@
+package model;
+
+/**
+ * 年级类型枚举
+ * 定义小学、初中、高中三个年级
+ */
+public enum GradeType {
+    /**
+     * 小学
+     */
+    PRIMARY,
+
+    /**
+     * 初中
+     */
+    MIDDLE,
+
+    /**
+     * 高中
+     */
+    HIGH
+}

src/model/Question.java

@@ -0,0 +1,64 @@
+package model;
+
+/**
+ * 题目类
+ * 包含题干、选项和正确答案
+ */
+public class Question {
+    private final String questionText;
+    private final String[] options;
+    private final int correctAnswer;
+    private final String expression;
+
+    /**
+     * 构造题目对象
+     *
+     * @param expression 数学表达式
+     * @param questionText 题目文本
+     * @param options 选项数组(4个选项)
+     * @param correctAnswer 正确答案索引(0-3)
+     */
+    public Question(String expression, String questionText, String[] options,
+                    int correctAnswer) {
+        this.expression = expression;
+        this.questionText = questionText;
+        this.options = options;
+        this.correctAnswer = correctAnswer;
+    }
+
+    /**
+     * 获取题目文本
+     *
+     * @return 题目文本
+     */
+    public String getQuestionText() {
+        return questionText;
+    }
+
+    /**
+     * 获取选项数组
+     *
+     * @return 选项数组
+     */
+    public String[] getOptions() {
+        return options;
+    }
+
+    /**
+     * 获取正确答案索引
+     *
+     * @return 正确答案索引
+     */
+    public int getCorrectAnswer() {
+        return correctAnswer;
+    }
+
+    /**
+     * 获取数学表达式
+     *
+     * @return 数学表达式
+     */
+    public String getExpression() {
+        return expression;
+    }
+}

src/model/QuestionGenerator.java

@@ -0,0 +1,509 @@
+package model;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Random;
+import java.util.Set;
+
+/**
+ * 题目生成器
+ * 根据年级生成相应难度的数学题目,支持查重功能
+ */
+public class QuestionGenerator {
+    private static final int MAX_ATTEMPTS = 100;
+    private final Random random;
+
+    /**
+     * 构造题目生成器
+     */
+    public QuestionGenerator() {
+        this.random = new Random();
+    }
+
+    /**
+     * 生成指定数量的题目
+     *
+     * @param gradeType 年级类型
+     * @param count 题目数量
+     * @param email 用户邮箱
+     * @return 题目列表
+     */
+    public List<Question> generateQuestions(GradeType gradeType,
+                                            int count, String email) {
+        List<Question> questions = new ArrayList<>();
+        Set<String> existingQuestions = loadUserQuestions(email);
+        Set<String> currentQuestions = new HashSet<>();
+        int attempts = 0;
+
+        while (questions.size() < count && attempts < MAX_ATTEMPTS) {
+            String expression = generateExpression(gradeType);
+
+            if (!existingQuestions.contains(expression) &&
+                    !currentQuestions.contains(expression)) {
+                try {
+                    double result = evaluateExpression(expression);
+                    Question question = createQuestion(expression, result);
+                    questions.add(question);
+                    currentQuestions.add(expression);
+                    existingQuestions.add(expression);
+                } catch (Exception e) {
+                    // 表达式无效,继续尝试
+                }
+            }
+            attempts++;
+        }
+
+        saveUserQuestions(email, new ArrayList<>(currentQuestions));
+        return questions;
+    }
+
+    /**
+     * 根据年级生成表达式
+     *
+     * @param gradeType 年级类型
+     * @return 数学表达式
+     */
+    private String generateExpression(GradeType gradeType) {
+        switch (gradeType) {
+            case PRIMARY:
+                return generatePrimaryExpression();
+            case MIDDLE:
+                return generateMiddleExpression();
+            case HIGH:
+                return generateHighExpression();
+            default:
+                return generatePrimaryExpression();
+        }
+    }
+
+    /**
+     * 生成小学数学表达式(包含括号)
+     *
+     * @return 数学表达式
+     */
+    private String generatePrimaryExpression() {
+        int termCount = random.nextInt(2) + 2; // 2或3个操作数
+        char[] operators = {'+', '-', '*', '/'};
+
+        int num1 = random.nextInt(100) + 1;
+        char op1 = operators[random.nextInt(operators.length)];
+        int num2;
+
+        // 为第一个操作符生成第二个操作数，并确保合法性
+        if (op1 == '-') {
+            num2 = random.nextInt(num1 + 1); // 确保 num1 >= num2
+        } else if (op1 == '/') {
+            List<Integer> divisors = getDivisors(num1);
+            num2 = divisors.get(random.nextInt(divisors.size()));
+        } else { // + or *
+            num2 = random.nextInt(20) + 1; // 乘法和加法的数小一点，避免结果过大
+        }
+
+        // 如果只有两个操作数，直接返回
+        if (termCount == 2) {
+            return String.format("%d %c %d", num1, op1, num2);
+        }
+
+        // --- 如果有三个操作数 ---
+        String firstPart = String.format("%d %c %d", num1, op1, num2);
+        double interimResult;
+        try {
+            interimResult = evaluateExpression(firstPart);
+        } catch (Exception e) {
+            // 如果第一部分计算出错（理论上不应该），则简化为两项操作
+            return firstPart;
+        }
+
+        // 确保中间结果为非负整数
+        if (interimResult < 0 || interimResult != (int)interimResult) {
+            return firstPart; // 不满足条件，提前返回两项操作
+        }
+
+        char op2 = operators[random.nextInt(operators.length)];
+        int num3;
+
+        // 为第二个操作符生成第三个操作数，并确保合法性
+        if (op2 == '-') {
+            num3 = random.nextInt((int) interimResult + 1); // 确保 interimResult >= num3
+        } else if (op2 == '/') {
+            if (interimResult == 0) { // 除数不能为0
+                 op2 = '+'; // 将操作符改为加法
+                 num3 = random.nextInt(20) + 1;
+            } else {
+                List<Integer> divisors = getDivisors((int)interimResult);
+                num3 = divisors.get(random.nextInt(divisors.size()));
+            }
+        } else { // + or *
+            num3 = random.nextInt(20) + 1;
+        }
+
+        // 随机决定是否以及如何添加括号
+        if (random.nextBoolean()) {
+            return String.format("(%d %c %d) %c %d", num1, op1, num2, op2, num3);
+        } else {
+            // 检查第二个操作符优先级是否高于第一个
+            if ((op2 == '*' || op2 == '/') && (op1 == '+' || op1 == '-')) {
+                 return String.format("%d %c (%d %c %d)", num1, op1, num2, op2, num3);
+            }
+            // 默认无括号或左侧括号
+            return String.format("%d %c %d %c %d", num1, op1, num2, op2, num3);
+        }
+    }
+
+    /**
+     * 获取一个数的所有正整数约数
+     * @param n 数字
+     * @return 约数列表
+     */
+    private List<Integer> getDivisors(int n) {
+        List<Integer> divisors = new ArrayList<>();
+        if (n == 0) {
+            divisors.add(1); // 除数不能为0，返回1作为安全值
+            return divisors;
+        }
+        n = Math.abs(n); // 处理可能的负数输入
+        for (int i = 1; i <= n; i++) {
+            if (n % i == 0) {
+                divisors.add(i);
+            }
+        }
+        return divisors;
+    }
+
+    /**
+     * 为表达式添加括号
+     *
+     * @param expression 原表达式
+     * @return 添加括号后的表达式
+     */
+    private String addBrackets(String expression) {
+        String[] parts = expression.split(" ");
+        if (parts.length >= 5 && random.nextBoolean()) {
+            int start = (random.nextInt((parts.length - 3) / 2) + 1) * 2;
+            int end = Math.min(start + 2, parts.length - 1);
+
+            StringBuilder result = new StringBuilder();
+            for (int i = 0; i < parts.length; i++) {
+                if (i == start) {
+                    result.append("( ");
+                }
+                result.append(parts[i]);
+                if (i == end) {
+                    result.append(" )");
+                }
+                if (i < parts.length - 1) {
+                    result.append(" ");
+                }
+            }
+            return result.toString();
+        }
+        return expression;
+    }
+
+    /**
+     * 生成初中数学表达式(包含平方和平方根)
+     *
+     * @return 数学表达式
+     */
+    private String generateMiddleExpression() {
+        int termCount = random.nextInt(2) + 2; // 2或3个项
+        StringBuilder expr = new StringBuilder();
+        char[] operators = {'+', '-', '*', '/'};
+        int specialOpIndex = random.nextInt(termCount); // 随机决定哪一项是特殊运算
+
+        for (int i = 0; i < termCount; i++) {
+            if (i > 0) {
+                char op = operators[random.nextInt(operators.length)];
+                expr.append(" ").append(op).append(" ");
+            }
+
+            if (i == specialOpIndex) {
+                // 强制生成特殊运算
+                if (random.nextBoolean()) {
+                    // 生成平方运算
+                    int num = random.nextInt(15) + 1; // 平方的底数小一些
+                    expr.append("pow(").append(num).append(",2)");
+                } else {
+                    // 生成开方运算, 确保是完全平方数
+                    int sqrtNum = random.nextInt(10) + 1; // 1-10
+                    int perfectSquare = sqrtNum * sqrtNum;
+                    expr.append("(√").append(perfectSquare).append(")");
+                }
+            } else {
+                expr.append(random.nextInt(100) + 1);
+            }
+        }
+        return expr.toString();
+    }
+
+    /**
+     * 生成高中数学表达式(包含三角函数)
+     *
+     * @return 数学表达式
+     */
+    private String generateHighExpression() {
+        int termCount = random.nextInt(2) + 2; // 2或3个项
+        StringBuilder expr = new StringBuilder();
+        char[] operators = {'+', '-', '*', '/'};
+        String[] functions = {"sin", "cos", "tan"};
+        int trigFuncIndex = random.nextInt(termCount); // 随机决定哪一项是三角函数
+
+        for (int i = 0; i < termCount; i++) {
+            if (i > 0) {
+                char op = operators[random.nextInt(operators.length)];
+                expr.append(" ").append(op).append(" ");
+            }
+
+            if (i == trigFuncIndex) {
+                // 强制生成三角函数
+                String func = functions[random.nextInt(functions.length)];
+                int angle;
+                if ("tan".equals(func)) {
+                    angle = random.nextInt(90); // tan的角度范围 0-89
+                } else {
+                    angle = random.nextInt(361); // sin/cos的角度范围 0-360
+                }
+                expr.append(func).append("(").append(angle).append(")");
+            } else {
+                expr.append(random.nextInt(100) + 1);
+            }
+        }
+        return expr.toString();
+    }
+
+    /**
+     * 计算表达式的值
+     *
+     * @param expression 数学表达式
+     * @return 计算结果
+     */
+    private double evaluateExpression(String expression) {
+        // 预处理表达式，将自定义格式转换为标准格式
+        String processedExpression = expression.replaceAll("√(\\d+)", "sqrt($1)");
+
+        try {
+            return eval(processedExpression);
+        } catch (Exception e) {
+            System.err.println("表达式求值失败: " + expression);
+            System.err.println("处理后: " + processedExpression);
+            e.printStackTrace();
+            throw new IllegalArgumentException("无效的表达式: " + expression, e);
+        }
+    }
+
+    /**
+     * 表达式求值器
+     *
+     * @param expr 表达式字符串
+     * @return 计算结果
+     */
+    private double eval(String expr) {
+        return new Object() {
+            int pos = -1;
+            int ch;
+
+            void nextChar() {
+                ch = (++pos < expr.length()) ? expr.charAt(pos) : -1;
+            }
+
+            boolean eat(int charToEat) {
+                while (ch == ' ') {
+                    nextChar();
+                }
+                if (ch == charToEat) {
+                    nextChar();
+                    return true;
+                }
+                return false;
+            }
+
+            double parse() {
+                nextChar();
+                double x = parseExpression();
+                if (pos < expr.length()) {
+                    throw new RuntimeException("Unexpected: " + (char) ch);
+                }
+                return x;
+            }
+
+            double parseExpression() {
+                double x = parseTerm();
+                for (;;) {
+                    if (eat('+')) {
+                        x += parseTerm();
+                    } else if (eat('-')) {
+                        x -= parseTerm();
+                    } else {
+                        return x;
+                    }
+                }
+            }
+
+            double parseTerm() {
+                double x = parseFactor();
+                for (;;) {
+                    if (eat('*')) {
+                        x *= parseFactor();
+                    } else if (eat('/')) {
+                        x /= parseFactor();
+                    } else {
+                        return x;
+                    }
+                }
+            }
+
+            double parseFactor() {
+                if (eat('+')) {
+                    return parseFactor();
+                }
+                if (eat('-')) {
+                    return -parseFactor();
+                }
+
+                double x;
+                int startPos = this.pos;
+                if (eat('(')) {
+                    x = parseExpression();
+                    eat(')');
+                } else if ((ch >= '0' && ch <= '9') || ch == '.') {
+                    while ((ch >= '0' && ch <= '9') || ch == '.') {
+                        nextChar();
+                    }
+                    x = Double.parseDouble(expr.substring(startPos, this.pos));
+                } else if (ch >= 'a' && ch <= 'z') {
+                    while (ch >= 'a' && ch <= 'z') {
+                        nextChar();
+                    }
+                    String func = expr.substring(startPos, this.pos);
+                    x = parseFactor();
+                    if (func.equals("sqrt")) {
+                        x = Math.sqrt(x);
+                    } else if (func.equals("sin")) {
+                        x = Math.sin(x);
+                    } else if (func.equals("cos")) {
+                        x = Math.cos(x);
+                    } else if (func.equals("tan")) {
+                        x = Math.tan(x);
+                    } else {
+                        throw new RuntimeException("Unknown function: " + func);
+                    }
+                } else {
+                    throw new RuntimeException("Unexpected: " + (char) ch);
+                }
+
+                return x;
+            }
+        }.parse();
+    }
+
+    /**
+     * 创建题目对象
+     *
+     * @param expression 数学表达式
+     * @param correctAnswer 正确答案
+     * @return 题目对象
+     */
+    private Question createQuestion(String expression, double correctAnswer) {
+        String questionText = "计算: " + expression + " = ?";
+        double[] options = new double[4];
+        int correctIndex = random.nextInt(4);
+
+        options[correctIndex] = correctAnswer;
+
+        for (int i = 0; i < 4; i++) {
+            if (i != correctIndex) {
+                double offset = (random.nextDouble() * 20 - 10);
+                if (Math.abs(offset) < 1) {
+                    offset = random.nextBoolean() ? 5 : -5;
+                }
+                options[i] = correctAnswer + offset;
+            }
+        }
+
+        String[] optionStrings = new String[4];
+        for (int i = 0; i < 4; i++) {
+            optionStrings[i] = String.format("%c. %.2f",
+                    (char) ('A' + i), options[i]);
+        }
+
+        return new Question(expression, questionText, optionStrings, correctIndex);
+    }
+
+    /**
+     * 加载用户历史题目
+     *
+     * @param email 用户邮箱
+     * @return 历史题目集合
+     */
+    private Set<String> loadUserQuestions(String email) {
+        Set<String> questions = new HashSet<>();
+        File userDir = new File("questions" + File.separator + email);
+
+        if (!userDir.exists() || !userDir.isDirectory()) {
+            return questions;
+        }
+
+        File[] files = userDir.listFiles((dir, name) -> name.endsWith(".txt"));
+        if (files == null) {
+            return questions;
+        }
+
+        for (File file : files) {
+            try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
+                String line;
+                while ((line = reader.readLine()) != null) {
+                    line = line.trim();
+                    if (line.matches("\\d+\\.\\s+.*")) {
+                        String question = line.substring(line.indexOf('.') + 1).trim();
+                        questions.add(question);
+                    }
+                }
+            } catch (IOException e) {
+                System.err.println("读取文件失败: " + e.getMessage());
+            }
+        }
+
+        return questions;
+    }
+
+    /**
+     * 保存用户题目到文件
+     *
+     * @param email 用户邮箱
+     * @param questions 题目列表
+     */
+    private void saveUserQuestions(String email, List<String> questions) {
+        File userDir = new File("questions" + File.separator + email);
+        if (!userDir.exists()) {
+            if (!userDir.mkdirs()) {
+                System.err.println("创建目录失败");
+                return;
+            }
+        }
+
+        LocalDateTime now = LocalDateTime.now();
+        String fileName = now.format(
+                DateTimeFormatter.ofPattern("yyyy-MM-dd-HH-mm-ss")) + ".txt";
+        File file = new File(userDir, fileName);
+
+        try (PrintWriter writer = new PrintWriter(new FileWriter(file))) {
+            for (int i = 0; i < questions.size(); i++) {
+                writer.println((i + 1) + ". " + questions.get(i));
+                if (i < questions.size() - 1) {
+                    writer.println();
+                }
+            }
+        } catch (IOException e) {
+            System.err.println("保存文件失败: " + e.getMessage());
+        }
+    }
+}

src/model/UserManager.java

@@ -0,0 +1,154 @@
+package model;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * 用户管理类
+ * 负责用户注册、登录、密码修改等功能
+ */
+public class UserManager {
+    private static final Map<String, UserInfo> users = new HashMap<>();
+    private static final Map<String, String> usernameToEmail = new HashMap<>(); // 用于检查用户名唯一性
+
+    /**
+     * 用户注册
+     *
+     * @param email 用户邮箱
+     * @param password 密码
+     * @param gradeType 年级类型
+     * @param username 用户名
+     * @return 注册是否成功
+     */
+    public boolean register(String email, String password, GradeType gradeType, String username) {
+        if (users.containsKey(email) || usernameToEmail.containsKey(username)) {
+            return false;
+        }
+        users.put(email, new UserInfo(email, password, gradeType, username));
+        usernameToEmail.put(username, email);
+        return true;
+    }
+
+    /**
+     * 用户登录
+     *
+     * @param email 用户邮箱
+     * @param password 密码
+     * @return 用户信息对象,登录失败返回null
+     */
+    public UserInfo login(String email, String password) {
+        UserInfo user = users.get(email);
+        if (user == null || !user.getPassword().equals(password)) {
+            return null;
+        }
+        return user;
+    }
+
+    /**
+     * 检查用户是否存在
+     *
+     * @param email 用户邮箱
+     * @return 用户是否存在
+     */
+    public boolean userExists(String email) {
+        return users.containsKey(email);
+    }
+
+    /**
+     * 检查用户名是否存在
+     *
+     * @param username 用户名
+     * @return 用户名是否存在
+     */
+    public boolean usernameExists(String username) {
+        return usernameToEmail.containsKey(username);
+    }
+
+    /**
+     * 修改密码
+     *
+     * @param email 用户邮箱
+     * @param oldPassword 原密码
+     * @param newPassword 新密码
+     * @return 修改是否成功
+     */
+    public boolean changePassword(String email, String oldPassword,
+                                  String newPassword) {
+        UserInfo user = users.get(email);
+        if (user == null || !user.getPassword().equals(oldPassword)) {
+            return false;
+        }
+        user.setPassword(newPassword);
+        return true;
+    }
+
+    /**
+     * 内部类：用户信息
+     */
+    public static class UserInfo {
+        private final String email;
+        private String password;
+        private final GradeType gradeType;
+        private final String username;
+
+        /**
+         * 构造用户信息
+         *
+         * @param email 邮箱
+         * @param password 密码
+         * @param gradeType 年级类型
+         * @param username 用户名
+         */
+        public UserInfo(String email, String password, GradeType gradeType, String username) {
+            this.email = email;
+            this.password = password;
+            this.gradeType = gradeType;
+            this.username = username;
+        }
+
+        /**
+         * 获取邮箱
+         *
+         * @return 邮箱
+         */
+        public String getEmail() {
+            return email;
+        }
+
+        /**
+         * 获取密码
+         *
+         * @return 密码
+         */
+        public String getPassword() {
+            return password;
+        }
+
+        /**
+         * 设置密码
+         *
+         * @param password 新密码
+         */
+        public void setPassword(String password) {
+            this.password = password;
+        }
+
+        /**
+         * 获取年级类型
+         *
+         * @return 年级类型
+         */
+        public GradeType getGradeType() {
+            return gradeType;
+        }
+
+        /**
+         * 获取用户名
+         *
+         * @return 用户名
+         */
+        public String getUsername() {
+            return username;
+        }
+    }
+}

src/ui/ChangePasswordDialog.java

@@ -0,0 +1,159 @@
+package ui;
+
+import model.UserManager;
+import javax.swing.BorderFactory;
+import javax.swing.JButton;
+import javax.swing.JDialog;
+import javax.swing.JLabel;
+import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.JPasswordField;
+import java.awt.Dimension;
+import java.awt.Font;
+import java.awt.Frame;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.Insets;
+import java.util.regex.Pattern;
+
+/**
+ * 修改密码对话框
+ * 用户在登录状态下可以修改密码
+ */
+public class ChangePasswordDialog extends JDialog {
+    private static final long serialVersionUID = 1L;
+    private static final Pattern PASSWORD_PATTERN =
+            Pattern.compile("^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)[a-zA-Z0-9]{6,10}$");
+
+    private final JPasswordField oldPasswordField;
+    private final JPasswordField newPassword1Field;
+    private final JPasswordField newPassword2Field;
+    private final JButton confirmButton;
+    private final UserManager userManager;
+    private final String email;
+
+    /**
+     * 构造修改密码对话框
+     *
+     * @param parent 父窗口
+     * @param email 用户邮箱
+     */
+    public ChangePasswordDialog(Frame parent, String email) {
+        super(parent, "修改密码", true);
+        this.email = email;
+        this.userManager = new UserManager();
+
+    setSize(600, 360);
+    setLocationRelativeTo(parent);
+    setResizable(true);
+
+        JPanel panel = new JPanel(new GridBagLayout());
+        panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(5, 5, 5, 5);
+        gbc.fill = GridBagConstraints.HORIZONTAL;
+
+        JLabel infoLabel = new JLabel("<html>新密码要求:<br>" +
+                "1. 长度 6-10位<br>" +
+                "2. 必须包含大写字母<br>" +
+                "3. 必须包含小写字母<br>" +
+                "4. 必须包含数字<br>" +
+                "5. 不能包含特殊字符</html>");
+        infoLabel.setFont(new Font("微软雅黑", Font.PLAIN, 11));
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        gbc.gridwidth = 2;
+        panel.add(infoLabel, gbc);
+
+        gbc.gridwidth = 1;
+        gbc.gridy = 1;
+        panel.add(new JLabel("原密码:"), gbc);
+
+    oldPasswordField = new JPasswordField(20);
+    gbc.gridx = 1;
+    gbc.weightx = 1.0;
+    panel.add(oldPasswordField, gbc);
+    gbc.weightx = 0.0;
+
+        gbc.gridx = 0;
+        gbc.gridy = 2;
+        panel.add(new JLabel("新密码:"), gbc);
+
+    newPassword1Field = new JPasswordField(20);
+    gbc.gridx = 1;
+    gbc.weightx = 1.0;
+    panel.add(newPassword1Field, gbc);
+    gbc.weightx = 0.0;
+
+        gbc.gridx = 0;
+        gbc.gridy = 3;
+        panel.add(new JLabel("确认新密码:"), gbc);
+
+    newPassword2Field = new JPasswordField(20);
+    gbc.gridx = 1;
+    gbc.weightx = 1.0;
+    panel.add(newPassword2Field, gbc);
+    gbc.weightx = 0.0;
+
+        confirmButton = new JButton("确认修改");
+        confirmButton.setPreferredSize(new Dimension(120, 30));
+        gbc.gridx = 0;
+        gbc.gridy = 4;
+        gbc.gridwidth = 2;
+        gbc.anchor = GridBagConstraints.CENTER;
+        panel.add(confirmButton, gbc);
+
+        add(panel);
+
+        confirmButton.addActionListener(e -> handleConfirm());
+        getRootPane().setDefaultButton(confirmButton);
+    }
+
+    /**
+     * 处理确认修改
+     */
+    private void handleConfirm() {
+        String oldPassword = new String(oldPasswordField.getPassword());
+        String newPassword1 = new String(newPassword1Field.getPassword());
+        String newPassword2 = new String(newPassword2Field.getPassword());
+
+        if (oldPassword.isEmpty() || newPassword1.isEmpty() ||
+                newPassword2.isEmpty()) {
+            showError("所有字段都不能为空");
+            return;
+        }
+
+        if (!newPassword1.equals(newPassword2)) {
+            showError("两次输入的新密码不一致");
+            return;
+        }
+
+        if (!PASSWORD_PATTERN.matcher(newPassword1).matches()) {
+            showError("新密码不符合要求:\n" +
+                    "长度6-10位, 必须包含大小写字母和数字, 且不能包含特殊字符");
+            return;
+        }
+
+        if (userManager.changePassword(email, oldPassword, newPassword1)) {
+            JOptionPane.showMessageDialog(this,
+                    "密码修改成功!",
+                    "成功",
+                    JOptionPane.INFORMATION_MESSAGE);
+            dispose();
+        } else {
+            showError("原密码错误");
+        }
+    }
+
+    /**
+     * 显示错误信息
+     *
+     * @param message 错误消息
+     */
+    private void showError(String message) {
+        JOptionPane.showMessageDialog(this,
+                message,
+                "错误",
+                JOptionPane.ERROR_MESSAGE);
+    }
+}

src/ui/GradeSelectionFrame.java

@@ -0,0 +1,234 @@
+package ui;
+
+import model.Grade;
+import model.UserManager;
+import javax.swing.BorderFactory;
+import javax.swing.JButton;
+import javax.swing.JComboBox;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.JSpinner;
+import javax.swing.SpinnerNumberModel;
+import java.awt.BorderLayout;
+import java.awt.Dimension;
+import java.awt.FlowLayout;
+import java.awt.Font;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.Insets;
+
+/**
+ * 年级选择和题目数量输入界面
+ * 用户可以选择年级、设置题目数量、用户设置或退出登录
+ */
+public class GradeSelectionFrame extends JFrame {
+    private static final long serialVersionUID = 1L;
+
+    private final String email;
+    private final String username;
+    private Grade currentGrade;
+    private final JLabel gradeLabel;
+    private final JComboBox<String> gradeComboBox;
+    private final JSpinner questionSpinner;
+    private final JButton startButton;
+    private final JButton userSettingsButton;
+    private final JButton logoutButton;
+
+    /**
+     * 构造年级选择界面（使用邮箱和年级）
+     *
+     * @param email 用户邮箱
+     * @param initialGrade 初始年级
+     */
+    public GradeSelectionFrame(String email, Grade initialGrade) {
+        this(email, initialGrade, email); // 默认显示邮箱作为用户名
+    }
+
+    /**
+     * 构造年级选择界面（使用 UserInfo 对象）
+     *
+     * @param userInfo 用户信息对象
+     */
+    public GradeSelectionFrame(UserManager.UserInfo userInfo) {
+        this(userInfo.getEmail(), userInfo.getGrade(), userInfo.getUsername());
+    }
+
+    /**
+     * 构造年级选择界面（完整构造函数）
+     *
+     * @param email 用户邮箱
+     * @param initialGrade 初始年级
+     * @param username 用户名
+     */
+    private GradeSelectionFrame(String email, Grade initialGrade, String username) {
+        this.email = email;
+        this.username = username;
+        this.currentGrade = initialGrade;
+
+        setTitle("数学学习软件 - 选择年级");
+        setSize(700, 450);
+        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+        setLocationRelativeTo(null);
+        setResizable(true);
+
+        JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+        mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+        // --- Top Panel ---
+        JPanel topPanel = new JPanel(new BorderLayout());
+
+        // 欢迎信息（显示用户名）
+        JLabel welcomeLabel = new JLabel("欢迎, " + username, JLabel.LEFT);
+        welcomeLabel.setFont(new Font("微软雅黑", Font.BOLD, 16));
+        topPanel.add(welcomeLabel, BorderLayout.WEST);
+
+        // 用户设置按钮（右上角）
+        userSettingsButton = new JButton("用户设置");
+        JPanel topRightPanel = new JPanel(new FlowLayout(FlowLayout.RIGHT, 0, 0));
+        topRightPanel.add(userSettingsButton);
+        topPanel.add(topRightPanel, BorderLayout.EAST);
+
+        // 当前年级显示
+        gradeLabel = new JLabel("当前年级: " + getGradeName(currentGrade),
+                JLabel.CENTER);
+        gradeLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+        gradeLabel.setBorder(BorderFactory.createEmptyBorder(10, 0, 0, 0));
+        topPanel.add(gradeLabel, BorderLayout.SOUTH);
+
+        mainPanel.add(topPanel, BorderLayout.NORTH);
+
+        // --- Center Panel ---
+        JPanel centerPanel = new JPanel(new GridBagLayout());
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(10, 5, 10, 5);
+        gbc.fill = GridBagConstraints.HORIZONTAL;
+
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        centerPanel.add(new JLabel("选择年级:"), gbc);
+
+        String[] grades = {"小学", "初中", "高中"};
+        gradeComboBox = new JComboBox<>(grades);
+        gradeComboBox.setSelectedItem(getGradeName(currentGrade));
+        gbc.gridx = 1;
+        gbc.weightx = 1.0;
+        centerPanel.add(gradeComboBox, gbc);
+        gbc.weightx = 0.0;
+
+        gbc.gridx = 0;
+        gbc.gridy = 1;
+        centerPanel.add(new JLabel("题目数量:"), gbc);
+
+        SpinnerNumberModel spinnerModel = new SpinnerNumberModel(10, 10, 30, 1);
+        questionSpinner = new JSpinner(spinnerModel);
+
+        // 禁用 JSpinner 的文本输入功能，只允许通过按钮调节
+        JSpinner.DefaultEditor editor = (JSpinner.DefaultEditor) questionSpinner.getEditor();
+        editor.getTextField().setEditable(false);
+
+        gbc.gridx = 1;
+        gbc.weightx = 1.0;
+        centerPanel.add(questionSpinner, gbc);
+        gbc.weightx = 0.0;
+
+        startButton = new JButton("开始答题");
+        startButton.setPreferredSize(new Dimension(200, 40));
+        startButton.setFont(new Font("微软雅黑", Font.BOLD, 14));
+        gbc.gridx = 0;
+        gbc.gridy = 2;
+        gbc.gridwidth = 2;
+        gbc.anchor = GridBagConstraints.CENTER;
+        centerPanel.add(startButton, gbc);
+
+        mainPanel.add(centerPanel, BorderLayout.CENTER);
+
+        // --- Bottom Panel ---
+        JPanel bottomPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 10, 0));
+        logoutButton = new JButton("退出登录");
+        bottomPanel.add(logoutButton);
+
+        mainPanel.add(bottomPanel, BorderLayout.SOUTH);
+
+        add(mainPanel);
+
+        // --- Action Listeners ---
+        startButton.addActionListener(e -> startQuiz());
+        userSettingsButton.addActionListener(e -> openUserSettings());
+        logoutButton.addActionListener(e -> logout());
+        gradeComboBox.addActionListener(e -> updateGrade());
+    }
+
+    /**
+     * 更新当前年级
+     */
+    private void updateGrade() {
+        String selected = (String) gradeComboBox.getSelectedItem();
+        switch (selected) {
+            case "小学":
+                currentGrade = Grade.primary;
+                break;
+            case "初中":
+                currentGrade = Grade.middle;
+                break;
+            case "高中":
+                currentGrade = Grade.high;
+                break;
+        }
+        gradeLabel.setText("当前年级: " + getGradeName(currentGrade));
+    }
+
+    /**
+     * 开始答题
+     */
+    private void startQuiz() {
+        int questionCount = (Integer) questionSpinner.getValue();
+        QuizFrame quizFrame = new QuizFrame(email, currentGrade, questionCount);
+        quizFrame.setVisible(true);
+        this.dispose();
+    }
+
+    /**
+     * 打开用户设置对话框
+     */
+    private void openUserSettings() {
+        UserSettingsDialog dialog = new UserSettingsDialog(this, email, username);
+        dialog.setVisible(true);
+    }
+
+    /**
+     * 退出登录
+     */
+    private void logout() {
+        int confirm = JOptionPane.showConfirmDialog(this,
+                "确定要退出登录吗?",
+                "确认",
+                JOptionPane.YES_NO_OPTION);
+
+        if (confirm == JOptionPane.YES_OPTION) {
+            LoginFrame loginFrame = new LoginFrame();
+            loginFrame.setVisible(true);
+            this.dispose();
+        }
+    }
+
+    /**
+     * 获取年级名称
+     *
+     * @param grade 年级类型
+     * @return 年级名称
+     */
+    private String getGradeName(Grade grade) {
+        switch (grade) {
+            case primary:
+                return "小学";
+            case middle:
+                return "初中";
+            case high:
+                return "高中";
+            default:
+                return "未知";
+        }
+    }
+}

src/ui/LoginFrame.java

@@ -0,0 +1,178 @@
+package ui;
+
+import model.UserManager;
+import javax.swing.BorderFactory;
+import javax.swing.JButton;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.JPasswordField;
+import javax.swing.JTextField;
+import java.awt.Dimension;
+import java.awt.FlowLayout;
+import java.awt.Font;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.Insets;
+
+/**
+ * 登录框界面类，处理用户登录和注册功能。
+ *
+ * <p>该类提供了一个图形界面，允许用户通过邮箱或用户名和密码登录系统，
+ * 或者跳转到注册界面创建新账户。此类使用{@link UserManager}处理具体的用户验证逻辑。
+ *
+ * @author 结对项目组
+ */
+public class LoginFrame extends JFrame {
+    private static final long serialVersionUID = 1L;
+
+    /** 邮箱/用户名输入框 */
+    private final JTextField accountField;
+    /** 密码输入框 */
+    private final JPasswordField passwordField;
+    /** 登录按钮 */
+    private final JButton loginButton;
+    /** 注册按钮 */
+    private final JButton registerButton;
+    /** 用户管理器，处理登录验证 */
+    private final UserManager userManager;
+
+    /**
+     * 创建并初始化登录界面。
+     *
+     * <p>设置界面布局，包括账号输入框、密码输入框、登录按钮和注册按钮。
+     * 初始化{@link UserManager}用于处理用户验证。
+     */
+    public LoginFrame() {
+        this.userManager = new UserManager();
+
+        setTitle("数学学习软件 - 登录");
+        setSize(600, 450);
+        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+        setLocationRelativeTo(null);
+        setResizable(true);
+
+        JPanel mainPanel = new JPanel(new GridBagLayout());
+        mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(5, 5, 5, 5);
+        gbc.fill = GridBagConstraints.HORIZONTAL;
+
+        // 标题
+        JLabel titleLabel = new JLabel("小初高数学学习系统", JLabel.CENTER);
+        titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 20));
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        gbc.gridwidth = 2;
+        mainPanel.add(titleLabel, gbc);
+
+        // 提示信息
+        JLabel hintLabel = new JLabel("支持邮箱或用户名登录", JLabel.CENTER);
+        hintLabel.setFont(new Font("微软雅黑", Font.PLAIN, 11));
+        hintLabel.setForeground(java.awt.Color.GRAY);
+        gbc.gridy = 1;
+        mainPanel.add(hintLabel, gbc);
+
+        // 账号输入
+        gbc.gridwidth = 1;
+        gbc.gridy = 2;
+        mainPanel.add(new JLabel("账号:"), gbc);
+
+        accountField = new JTextField(25);
+        gbc.gridx = 1;
+        gbc.weightx = 1.0;
+        mainPanel.add(accountField, gbc);
+        gbc.weightx = 0.0;
+
+        // 密码输入
+        gbc.gridx = 0;
+        gbc.gridy = 3;
+        mainPanel.add(new JLabel("密码:"), gbc);
+
+        passwordField = new JPasswordField(25);
+        gbc.gridx = 1;
+        gbc.weightx = 1.0;
+        mainPanel.add(passwordField, gbc);
+        gbc.weightx = 0.0;
+
+        // 按钮面板
+        JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 10, 0));
+        loginButton = new JButton("登录");
+        registerButton = new JButton("注册");
+
+        loginButton.setPreferredSize(new Dimension(100, 30));
+        registerButton.setPreferredSize(new Dimension(100, 30));
+
+        buttonPanel.add(loginButton);
+        buttonPanel.add(registerButton);
+
+        gbc.gridx = 0;
+        gbc.gridy = 4;
+        gbc.gridwidth = 2;
+        mainPanel.add(buttonPanel, gbc);
+
+        add(mainPanel);
+
+        // 事件监听
+        loginButton.addActionListener(e -> handleLogin());
+        registerButton.addActionListener(e -> handleRegister());
+
+        getRootPane().setDefaultButton(loginButton);
+    }
+
+    /**
+     * 处理用户登录请求。
+     *
+     * <p>验证用户输入的账号（邮箱或用户名）和密码，如果验证成功则打开年级选择界面，
+     * 否则显示错误消息。
+     */
+    private void handleLogin() {
+        String account = accountField.getText().trim();
+        String password = new String(passwordField.getPassword());
+
+        if (account.isEmpty() || password.isEmpty()) {
+            JOptionPane.showMessageDialog(this,
+                    "账号和密码不能为空",
+                    "错误",
+                    JOptionPane.ERROR_MESSAGE);
+            return;
+        }
+
+        // 使用新的登录方法，支持邮箱或用户名
+        UserManager.UserInfo userInfo = userManager.loginWithEmailOrUsername(account, password);
+
+        if (userInfo != null) {
+            openGradeSelection(userInfo);
+        } else {
+            JOptionPane.showMessageDialog(this,
+                    "账号或密码错误",
+                    "登录失败",
+                    JOptionPane.ERROR_MESSAGE);
+        }
+    }
+
+    /**
+     * 显示注册对话框。
+     *
+     * <p>创建并显示{@link RegisterDialog}，允许新用户注册账号。
+     */
+    private void handleRegister() {
+        RegisterDialog dialog = new RegisterDialog(this, userManager);
+        dialog.setVisible(true);
+    }
+
+    /**
+     * 打开年级选择界面。
+     *
+     * <p>用户登录成功后，创建并显示{@link GradeSelectionFrame}，
+     * 同时关闭当前登录窗口。
+     *
+     * @param userInfo 包含用户所有信息的对象
+     */
+    private void openGradeSelection(UserManager.UserInfo userInfo) {
+        GradeSelectionFrame gradeFrame = new GradeSelectionFrame(userInfo);
+        gradeFrame.setVisible(true);
+        this.dispose();
+    }
+}

src/ui/MathLearningApp.java

@@ -0,0 +1,24 @@
+package ui;
+
+import javax.swing.SwingUtilities;
+
+/**
+ * 数学学习软件主入口
+ *
+ * @author 结对项目
+ * @version 1.0
+ */
+public class MathLearningApp {
+
+    /**
+     * 程序主入口
+     *
+     * @param args 命令行参数
+     */
+    public static void main(String[] args) {
+        SwingUtilities.invokeLater(() -> {
+            LoginFrame loginFrame = new LoginFrame();
+            loginFrame.setVisible(true);
+        });
+    }
+}

src/ui/PasswordSetupDialog.java

@@ -0,0 +1,215 @@
+package ui;
+
+import model.Grade;
+import model.UserManager;
+import javax.swing.BorderFactory;
+import javax.swing.JButton;
+import javax.swing.JComboBox;
+import javax.swing.JDialog;
+import javax.swing.JLabel;
+import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.JPasswordField;
+import javax.swing.JTextField;
+import java.awt.Dimension;
+import java.awt.Frame;
+import java.awt.Font;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.Insets;
+import java.io.Serial;
+import java.util.regex.Pattern;
+
+/**
+ * 密码设置对话框
+ * 用于新用户注册时设置密码和选择年级
+ */
+public class PasswordSetupDialog extends JDialog {
+    @Serial
+    private static final long serialVersionUID = 1L;
+    private static final Pattern PASSWORD_PATTERN =
+            Pattern.compile("^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)[a-zA-Z0-9]{6,10}$");
+
+    private final JTextField usernameField;
+    private final JPasswordField password1Field;
+    private final JPasswordField password2Field;
+    private final JComboBox<String> gradeComboBox;
+    private final JButton confirmButton;
+    private final UserManager userManager;
+    private final String email;
+    private boolean registrationComplete;
+
+    /**
+     * 构造密码设置对话框
+     *
+     * @param parent 父窗口
+     * @param userManager 用户管理器
+     * @param email 用户邮箱
+     */
+    public PasswordSetupDialog(Frame parent, UserManager userManager, String email) {
+        super(parent, "设置密码和用户名", true);
+        this.userManager = userManager;
+        this.email = email;
+        this.registrationComplete = false;
+
+    setSize(600, 420);
+    setLocationRelativeTo(parent);
+    setResizable(true);
+
+        JPanel panel = new JPanel(new GridBagLayout());
+        panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(5, 5, 5, 5);
+        gbc.fill = GridBagConstraints.HORIZONTAL;
+
+        JLabel infoLabel = new JLabel("<html>密码要求:<br>" +
+                "1. 长度 6-10位<br>" +
+                "2. 必须包含大写字母<br>" +
+                "3. 必须包含小写字母<br>" +
+                "4. 必须包含数字<br>" +
+                "5. 不能包含其他特殊字符</html>");
+        infoLabel.setFont(new Font("微软雅黑", Font.PLAIN, 11));
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        gbc.gridwidth = 2;
+        panel.add(infoLabel, gbc);
+
+        gbc.gridwidth = 1;
+        gbc.gridy = 1;
+        panel.add(new JLabel("输入密码:"), gbc);
+
+    password1Field = new JPasswordField(20);
+        gbc.gridx = 1;
+    gbc.weightx = 1.0;
+    panel.add(password1Field, gbc);
+    gbc.weightx = 0.0;
+
+        gbc.gridx = 0;
+        gbc.gridy = 2;
+        panel.add(new JLabel("确认密码:"), gbc);
+
+    password2Field = new JPasswordField(20);
+        gbc.gridx = 1;
+    gbc.weightx = 1.0;
+    panel.add(password2Field, gbc);
+    gbc.weightx = 0.0;
+
+        gbc.gridx = 0;
+        gbc.gridy = 3;
+        panel.add(new JLabel("设置用户名:"), gbc);
+
+        usernameField = new JTextField(20);
+        gbc.gridx = 1;
+        gbc.weightx = 1.0;
+        panel.add(usernameField, gbc);
+        gbc.weightx = 0.0;
+
+        gbc.gridx = 0;
+        gbc.gridy = 4;
+        panel.add(new JLabel("选择年级:"), gbc);
+
+        String[] grades = {"小学", "初中", "高中"};
+        gradeComboBox = new JComboBox<>(grades);
+        gbc.gridx = 1;
+        gbc.weightx = 1.0;
+        panel.add(gradeComboBox, gbc);
+        gbc.weightx = 0.0;
+
+        confirmButton = new JButton("确认注册");
+        confirmButton.setPreferredSize(new Dimension(120, 30));
+        gbc.gridx = 0;
+        gbc.gridy = 5;
+        gbc.gridwidth = 2;
+        gbc.anchor = GridBagConstraints.CENTER;
+        panel.add(confirmButton, gbc);
+
+        add(panel);
+
+        confirmButton.addActionListener(e -> handleConfirm());
+        getRootPane().setDefaultButton(confirmButton);
+    }
+
+    /**
+     * 处理确认注册
+     */
+    private void handleConfirm() {
+        String password1 = new String(password1Field.getPassword());
+        String password2 = new String(password2Field.getPassword());
+        String username = usernameField.getText().trim();
+
+        if (username.isEmpty() || password1.isEmpty() || password2.isEmpty()) {
+            showError("用户名和密码不能为空");
+            return;
+        }
+
+        if (userManager.usernameExists(username)) {
+            showError("该用户名已被使用，请更换一个");
+            return;
+        }
+
+        if (!password1.equals(password2)) {
+            showError("两次输入的密码不一致");
+            return;
+        }
+
+        if (!PASSWORD_PATTERN.matcher(password1).matches()) {
+            showError("密码不符合要求:\n" +
+                    "长度6-10位, 必须包含大小写字母和数字, 且不能包含特殊字符");
+            return;
+        }
+
+        Grade gradeType = getSelectedGradeType();
+        boolean success = userManager.register(email, password1, gradeType, username);
+
+        if (success) {
+            JOptionPane.showMessageDialog(this,
+                    "注册成功！请返回登录。",
+                    "成功",
+                    JOptionPane.INFORMATION_MESSAGE);
+            registrationComplete = true;
+            dispose();
+        } else {
+            showError("注册失败，该邮箱可能已被注册");
+        }
+    }
+
+    /**
+     * 获取选择的年级类型
+     *
+     * @return 年级类型
+     */
+    private Grade getSelectedGradeType() {
+        String selected = (String) gradeComboBox.getSelectedItem();
+        switch (selected) {
+            case "小学":
+                return Grade.primary;
+            case "初中":
+                return Grade.middle;
+            case "高中":
+                return Grade.high;
+            default:
+                return Grade.primary;
+        }
+    }
+
+    /**
+     * 显示错误信息
+     *
+     * @param message 错误消息
+     */
+    private void showError(String message) {
+        JOptionPane.showMessageDialog(this,
+                message,
+                "错误",
+                JOptionPane.ERROR_MESSAGE);
+    }
+
+    /**
+     * 检查注册是否完成
+     *
+     * @return 注册是否完成
+     */
+    public boolean isRegistrationComplete() {
+        return registrationComplete;
+    }
+}

src/ui/QuizFrame.java

@@ -0,0 +1,210 @@
+package ui;
+
+import model.Grade;
+import model.Question;
+import model.QuestionMaker;
+
+import javax.swing.BorderFactory;
+import javax.swing.ButtonGroup;
+import javax.swing.JButton;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.JRadioButton;
+import java.awt.BorderLayout;
+import java.awt.Dimension;
+import java.awt.FlowLayout;
+import java.awt.Font;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.Insets;
+import java.io.Serial;
+import java.util.List;
+
+/**
+ * 答题界面
+ * 显示题目和选项,接收用户答案
+ */
+public class QuizFrame extends JFrame {
+    @Serial
+    private static final long serialVersionUID = 1L;
+
+    private final String email;
+    private final Grade gradeType;
+    private final List<Question> questions;
+    private int currentIndex;
+    private int correctCount;
+
+    private JLabel questionLabel;
+    private JLabel progressLabel;
+    private JRadioButton[] optionButtons;
+    private JButton submitButton;
+    private ButtonGroup optionGroup;
+
+    /**
+     * 构造答题界面
+     *
+     * @param email 用户邮箱
+     * @param gradeType 年级类型
+     * @param questionCount 题目数量
+     */
+    public QuizFrame(String email, Grade gradeType, int questionCount) {
+        this.email = email;
+        this.gradeType = gradeType;
+        this.currentIndex = 0;
+        this.correctCount = 0;
+
+            QuestionMaker generator = new QuestionMaker();
+        this.questions = generator.makeQuestions(gradeType, questionCount, email);
+
+        if (questions.isEmpty()) {
+            JOptionPane.showMessageDialog(null,
+                    "生成题目失败,返回主界面",
+                    "错误",
+                    JOptionPane.ERROR_MESSAGE);
+            returnToGradeSelection();
+            return;
+        }
+
+        setTitle("数学学习软件 - 答题");
+    setSize(900, 600);
+    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    setLocationRelativeTo(null);
+    setResizable(true);
+
+        JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+        mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+        progressLabel = new JLabel("", JLabel.CENTER);
+        progressLabel.setFont(new Font("微软雅黑", Font.BOLD, 14));
+        mainPanel.add(progressLabel, BorderLayout.NORTH);
+
+        JPanel centerPanel = new JPanel(new GridBagLayout());
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(10, 10, 10, 10);
+        gbc.fill = GridBagConstraints.HORIZONTAL;
+
+        // 新增：答案格式提示
+        JLabel answerFormatLabel = new JLabel("注意：所有计算结果的答案均保留两位小数。", JLabel.CENTER);
+        answerFormatLabel.setFont(new Font("微软雅黑", Font.ITALIC, 12));
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        gbc.gridwidth = 2;
+        centerPanel.add(answerFormatLabel, gbc);
+
+        gbc.gridx = 0;
+        gbc.gridy = 1;
+        gbc.gridwidth = 2;
+
+        questionLabel = new JLabel();
+    questionLabel.setFont(new Font("Cambria Math", Font.PLAIN, 18));
+    questionLabel.setBorder(BorderFactory.createEmptyBorder(10, 10, 20, 10));
+        centerPanel.add(questionLabel, gbc);
+
+        optionGroup = new ButtonGroup();
+        optionButtons = new JRadioButton[4];
+
+        for (int i = 0; i < 4; i++) {
+            optionButtons[i] = new JRadioButton();
+            optionButtons[i].setFont(new Font("Cambria Math", Font.PLAIN, 14));
+            optionGroup.add(optionButtons[i]);
+            gbc.gridy = i + 2;
+            gbc.gridwidth = 2;
+            centerPanel.add(optionButtons[i], gbc);
+            gbc.gridwidth = 1;
+        }
+
+        mainPanel.add(centerPanel, BorderLayout.CENTER);
+
+        JPanel bottomPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
+        submitButton = new JButton("提交答案");
+        submitButton.setPreferredSize(new Dimension(150, 35));
+        submitButton.setFont(new Font("微软雅黑", Font.BOLD, 14));
+        bottomPanel.add(submitButton);
+
+        mainPanel.add(bottomPanel, BorderLayout.SOUTH);
+
+        add(mainPanel);
+
+        submitButton.addActionListener(e -> handleSubmit());
+
+        displayQuestion();
+    }
+
+    /**
+     * 显示当前题目
+     */
+    private void displayQuestion() {
+        if (currentIndex >= questions.size()) {
+            showResult();
+            return;
+        }
+
+        Question question = questions.get(currentIndex);
+        progressLabel.setText(String.format("第 %d/%d 题",
+                currentIndex + 1, questions.size()));
+        questionLabel.setText("<html><body style='width: 500px'>" +
+                question.getQuestionText() + "</body></html>");
+
+        optionGroup.clearSelection();
+
+        String[] options = question.getOptions();
+        for (int i = 0; i < 4; i++) {
+            optionButtons[i].setText(options[i]);
+        }
+
+        submitButton.setEnabled(true);
+    }
+
+    /**
+     * 处理答案提交
+     */
+    private void handleSubmit() {
+        int selectedIndex = -1;
+        for (int i = 0; i < 4; i++) {
+            if (optionButtons[i].isSelected()) {
+                selectedIndex = i;
+                break;
+            }
+        }
+
+        if (selectedIndex == -1) {
+            JOptionPane.showMessageDialog(this,
+                    "请选择一个答案",
+                    "提示",
+                    JOptionPane.WARNING_MESSAGE);
+            return;
+        }
+
+        Question question = questions.get(currentIndex);
+        if (selectedIndex == question.getCorrectAnswer()) {
+            correctCount++;
+        }
+
+        currentIndex++;
+        displayQuestion();
+    }
+
+    /**
+     * 显示答题结果
+     */
+    private void showResult() {
+        double percentage = (double) correctCount / questions.size() * 100;
+        int score = (int) percentage;
+
+        ResultFrame resultFrame = new ResultFrame(
+                email, gradeType, score, correctCount, questions.size());
+        resultFrame.setVisible(true);
+        this.dispose();
+    }
+
+    /**
+     * 返回年级选择界面
+     */
+    private void returnToGradeSelection() {
+        GradeSelectionFrame frame = new GradeSelectionFrame(email, gradeType);
+        frame.setVisible(true);
+        this.dispose();
+    }
+}

src/ui/RegisterDialog.java

@@ -0,0 +1,278 @@
+package ui;
+
+import model.UserManager;
+import javax.swing.BorderFactory;
+import javax.swing.JButton;
+import javax.swing.JDialog;
+import javax.swing.JLabel;
+import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.JTextField;
+import javax.swing.SwingWorker;
+import java.awt.Frame;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.Insets;
+import java.util.Properties;
+import java.util.regex.Pattern;
+import javax.mail.Authenticator;
+import javax.mail.Message;
+import javax.mail.MessagingException;
+import javax.mail.PasswordAuthentication;
+import javax.mail.Session;
+import javax.mail.Transport;
+import javax.mail.internet.InternetAddress;
+import javax.mail.internet.MimeMessage;
+
+/**
+ * 用户注册对话框
+ * 实现邮箱验证码注册功能
+ */
+public class RegisterDialog extends JDialog {
+    private static final long serialVersionUID = 1L;
+    private static final Pattern EMAIL_PATTERN =
+            Pattern.compile("^[A-Za-z0-9+_.-]+@qq\\.com$");
+
+    // 邮件配置 - 请根据实际情况修改
+    private static final String SMTP_HOST = "smtp.qq.com";  // QQ邮箱SMTP服务器
+    private static final String SMTP_PORT = "587";  // 或使用465(SSL)
+    private static final String FROM_EMAIL = "3551664030@qq.com";  // 发件人邮箱
+    private static final String EMAIL_PASSWORD = "wvazqphcxhuqdbfa";  // 授权码(非登录密码)
+
+    private final JTextField emailField;
+    private final JTextField codeField;
+    private final JButton sendCodeButton;
+    private final JButton verifyButton;
+    private final UserManager userManager;
+    private String generatedCode;
+
+    /**
+     * 构造注册对话框
+     *
+     * @param parent 父窗口
+     * @param userManager 用户管理器
+     */
+    public RegisterDialog(Frame parent, UserManager userManager) {
+        super(parent, "用户注册", true);
+        this.userManager = userManager;
+
+        setSize(600, 300);
+        setLocationRelativeTo(parent);
+        setResizable(false);
+
+        JPanel panel = new JPanel(new GridBagLayout());
+        panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(5, 5, 5, 5);
+        gbc.fill = GridBagConstraints.HORIZONTAL;
+
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        panel.add(new JLabel("邮箱:"), gbc);
+
+        emailField = new JTextField(25);
+        gbc.gridx = 1;
+        gbc.gridwidth = 2;
+        panel.add(emailField, gbc);
+
+        sendCodeButton = new JButton("发送验证码");
+        gbc.gridx = 3;
+        gbc.gridwidth = 1;
+        panel.add(sendCodeButton, gbc);
+
+        gbc.gridx = 0;
+        gbc.gridy = 1;
+        panel.add(new JLabel("验证码:"), gbc);
+
+        codeField = new JTextField(25);
+        codeField.setEnabled(false);
+        gbc.gridx = 1;
+        gbc.gridwidth = 2;
+        panel.add(codeField, gbc);
+
+        verifyButton = new JButton("验证");
+        verifyButton.setEnabled(false);
+        gbc.gridx = 3;
+        gbc.gridwidth = 1;
+        panel.add(verifyButton, gbc);
+
+        add(panel);
+
+        sendCodeButton.addActionListener(e -> sendVerificationCode());
+        verifyButton.addActionListener(e -> verifyCode());
+    }
+
+    /**
+     * 发送验证码
+     */
+    private void sendVerificationCode() {
+        String email = emailField.getText().trim();
+
+        if (email.isEmpty()) {
+            showError("邮箱不能为空");
+            return;
+        }
+
+        if (!EMAIL_PATTERN.matcher(email).matches()) {
+            showError("请输入有效的QQ邮箱(以@qq.com结尾)");
+            return;
+        }
+
+        if (userManager.userExists(email)) {
+            showError("该邮箱已注册");
+            return;
+        }
+
+        generatedCode = generateCode();
+
+        // 禁用按钮，防止重复点击
+        sendCodeButton.setEnabled(false);
+        sendCodeButton.setText("发送中...");
+
+        // 使用SwingWorker在后台线程发送邮件，避免阻塞UI
+        new SwingWorker<Boolean, Void>() {
+            @Override
+            protected Boolean doInBackground() {
+                return sendEmail(email, generatedCode);
+            }
+
+            @Override
+            protected void done() {
+                try {
+                    boolean success = get();
+                    if (success) {
+                        JOptionPane.showMessageDialog(
+                                RegisterDialog.this,
+                                "验证码已发送到您的邮箱，请查收！",
+                                "发送成功",
+                                JOptionPane.INFORMATION_MESSAGE);
+
+                        emailField.setEnabled(false);
+                        codeField.setEnabled(true);
+                        verifyButton.setEnabled(true);
+                        sendCodeButton.setText("已发送");
+                    } else {
+                        showError("验证码发送失败，请检查邮箱地址或稍后重试");
+                        sendCodeButton.setEnabled(true);
+                        sendCodeButton.setText("发送验证码");
+                    }
+                } catch (Exception e) {
+                    showError("验证码发送失败: " + e.getMessage());
+                    sendCodeButton.setEnabled(true);
+                    sendCodeButton.setText("发送验证码");
+                }
+            }
+        }.execute();
+    }
+
+    /**
+     * 发送邮件
+     *
+     * @param toEmail 收件人邮箱
+     * @param code 验证码
+     * @return 是否发送成功
+     */
+    private boolean sendEmail(String toEmail, String code) {
+        try {
+            // 配置邮件服务器属性
+            Properties props = new Properties();
+            props.put("mail.smtp.host", SMTP_HOST);
+            props.put("mail.smtp.port", SMTP_PORT);
+            props.put("mail.smtp.auth", "true");
+            props.put("mail.smtp.starttls.enable", "true");  // 启用TLS
+            // 如果使用SSL端口465，取消下面两行注释
+            // props.put("mail.smtp.ssl.enable", "true");
+            // props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
+
+            // 创建会话
+            Session session = Session.getInstance(props, new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(FROM_EMAIL, EMAIL_PASSWORD);
+                }
+            });
+
+            // 创建邮件消息
+            Message message = new MimeMessage(session);
+            message.setFrom(new InternetAddress(FROM_EMAIL));
+            message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toEmail));
+            message.setSubject("注册验证码");
+
+            // 邮件内容
+            String content = String.format(
+                    "<html><body>" +
+                            "<h2>欢迎注册</h2>" +
+                            "<p>您的验证码是：<strong style='font-size: 24px; color: #007bff;'>%s</strong></p>" +
+                            "<p>验证码有效期为10分钟，请及时使用。</p>" +
+                            "<p>如果这不是您的操作，请忽略此邮件。</p>" +
+                            "</body></html>",
+                    code
+            );
+            message.setContent(content, "text/html; charset=utf-8");
+
+            // 发送邮件
+            Transport.send(message);
+            return true;
+
+        } catch (MessagingException e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+
+    /**
+     * 验证验证码
+     */
+    private void verifyCode() {
+        String inputCode = codeField.getText().trim();
+
+        if (inputCode.isEmpty()) {
+            showError("请输入验证码");
+            return;
+        }
+
+        if (!inputCode.equals(generatedCode)) {
+            showError("验证码错误");
+            return;
+        }
+
+        openPasswordDialog();
+    }
+
+    /**
+     * 打开密码设置对话框
+     */
+    private void openPasswordDialog() {
+        String email = emailField.getText().trim();
+        PasswordSetupDialog passwordDialog = new PasswordSetupDialog(
+                (Frame) getOwner(),
+                userManager,
+                email);
+        passwordDialog.setVisible(true);
+
+        if (passwordDialog.isRegistrationComplete()) {
+            dispose();
+        }
+    }
+
+    /**
+     * 生成6位数字验证码
+     *
+     * @return 验证码字符串
+     */
+    private String generateCode() {
+        return String.format("%06d", (int) (Math.random() * 1000000));
+    }
+
+    /**
+     * 显示错误信息
+     *
+     * @param message 错误消息
+     */
+    private void showError(String message) {
+        JOptionPane.showMessageDialog(this,
+                message,
+                "错误",
+                JOptionPane.ERROR_MESSAGE);
+    }
+}

src/ui/ResultFrame.java

@@ -0,0 +1,127 @@
+package ui;
+
+import model.Grade;
+import javax.swing.BorderFactory;
+import javax.swing.JButton;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+import java.awt.BorderLayout;
+import java.awt.Color;
+import java.awt.Dimension;
+import java.awt.FlowLayout;
+import java.awt.Font;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.Insets;
+
+/**
+ * 答题结果展示界面
+ * 显示得分和统计信息,提供继续答题或退出选项
+ */
+public class ResultFrame extends JFrame {
+    private static final long serialVersionUID = 1L;
+
+    private final String email;
+    private final Grade gradeType;
+
+    /**
+     * 构造结果展示界面
+     *
+     * @param email 用户邮箱
+     * @param gradeType 年级类型
+     * @param score 得分
+     * @param correctCount 答对题数
+     * @param totalCount 总题数
+     */
+    public ResultFrame(String email, Grade gradeType, int score,
+                       int correctCount, int totalCount) {
+        this.email = email;
+        this.gradeType = gradeType;
+
+        setTitle("数学学习软件 - 答题结果");
+    setSize(600, 420);
+    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    setLocationRelativeTo(null);
+    setResizable(true);
+
+        JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+        mainPanel.setBorder(BorderFactory.createEmptyBorder(30, 30, 30, 30));
+
+        JPanel centerPanel = new JPanel(new GridBagLayout());
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(10, 10, 10, 10);
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+
+        JLabel titleLabel = new JLabel("答题完成!", JLabel.CENTER);
+        titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 24));
+        centerPanel.add(titleLabel, gbc);
+
+        gbc.gridy = 1;
+        JLabel scoreLabel = new JLabel("得分: " + score, JLabel.CENTER);
+        scoreLabel.setFont(new Font("微软雅黑", Font.BOLD, 36));
+        scoreLabel.setForeground(getScoreColor(score));
+        centerPanel.add(scoreLabel, gbc);
+
+        gbc.gridy = 2;
+        JLabel detailLabel = new JLabel(
+                String.format("答对 %d 题 / 共 %d 题", correctCount, totalCount),
+                JLabel.CENTER);
+        detailLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+        centerPanel.add(detailLabel, gbc);
+
+        mainPanel.add(centerPanel, BorderLayout.CENTER);
+
+        JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 15, 0));
+        JButton continueButton = new JButton("继续做题");
+        JButton exitButton = new JButton("退出");
+
+        continueButton.setPreferredSize(new Dimension(120, 35));
+        exitButton.setPreferredSize(new Dimension(120, 35));
+
+        buttonPanel.add(continueButton);
+        buttonPanel.add(exitButton);
+
+        mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+
+        add(mainPanel);
+
+        continueButton.addActionListener(e -> continueQuiz());
+        exitButton.addActionListener(e -> exitToSelection());
+    }
+
+    /**
+     * 根据分数返回对应颜色
+     *
+     * @param score 分数
+     * @return 颜色对象
+     */
+    private Color getScoreColor(int score) {
+        if (score >= 90) {
+            return new Color(0, 150, 0);
+        } else if (score >= 60) {
+            return new Color(255, 140, 0);
+        } else {
+            return new Color(200, 0, 0);
+        }
+    }
+
+    /**
+     * 继续做题
+     */
+    private void continueQuiz() {
+        GradeSelectionFrame frame = new GradeSelectionFrame(email, gradeType);
+        frame.setVisible(true);
+        this.dispose();
+    }
+
+    /**
+     * 退出到选择界面
+     */
+    private void exitToSelection() {
+        GradeSelectionFrame frame = new GradeSelectionFrame(email, gradeType);
+        frame.setVisible(true);
+        this.dispose();
+    }
+}

src/ui/UserSettingsDialog.java

@@ -0,0 +1,86 @@
+package ui;
+
+import javax.swing.*;
+import java.awt.*;
+
+/**
+ * 用户设置对话框
+ * 显示用户信息并提供修改密码的入口
+ */
+public class UserSettingsDialog extends JDialog {
+    private static final long serialVersionUID = 1L;
+
+    private final String email;
+    private final String username;
+    private final Frame parentFrame;
+
+    /**
+     * 构造用户设置对话框
+     *
+     * @param parent   父窗口
+     * @param email    用户邮箱
+     * @param username 用户名
+     */
+    public UserSettingsDialog(Frame parent, String email, String username) {
+        super(parent, "用户设置", true);
+        this.parentFrame = parent;
+        this.email = email;
+        this.username = username;
+
+        setSize(400, 250);
+        setLocationRelativeTo(parent);
+        setResizable(false);
+
+        JPanel panel = new JPanel(new GridBagLayout());
+        panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(10, 5, 10, 5);
+        gbc.anchor = GridBagConstraints.WEST;
+
+        // 显示用户名
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        panel.add(new JLabel("用户名:"), gbc);
+
+        gbc.gridx = 1;
+        JLabel usernameLabel = new JLabel(username);
+        usernameLabel.setFont(new Font("微软雅黑", Font.BOLD, 14));
+        panel.add(usernameLabel, gbc);
+
+        // 显示邮箱
+        gbc.gridx = 0;
+        gbc.gridy = 1;
+        panel.add(new JLabel("邮箱:"), gbc);
+
+        gbc.gridx = 1;
+        JLabel emailLabel = new JLabel(email);
+        emailLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+        panel.add(emailLabel, gbc);
+
+        // 修改密码按钮
+        JButton changePasswordButton = new JButton("修改密码");
+        changePasswordButton.setPreferredSize(new Dimension(120, 30));
+        gbc.gridx = 0;
+        gbc.gridy = 2;
+        gbc.gridwidth = 2;
+        gbc.anchor = GridBagConstraints.CENTER;
+        gbc.insets = new Insets(20, 5, 10, 5);
+        panel.add(changePasswordButton, gbc);
+
+        add(panel);
+
+        // 按钮点击事件
+        changePasswordButton.addActionListener(e -> openChangePasswordDialog());
+    }
+
+    /**
+     * 打开修改密码对话框
+     */
+    private void openChangePasswordDialog() {
+        // 关闭当前对话框
+        this.dispose();
+        // 打开修改密码对话框
+        ChangePasswordDialog dialog = new ChangePasswordDialog(parentFrame, email);
+        dialog.setVisible(true);
+    }
+}