Java Swing 图形用户界面实验 —— 从算术练习到游戏开发的完整实践

项目一：小学生算术练习系统
1.1 需求分析
支持 + − × ÷ 四种运算，操作数涵盖整数、小数、分数
四种难度梯度：简单 → 中等 → 困难 → 专家
随机出题、按键提交、实时反馈、错题回顾
计时计分，进度条显示
1.2 架构设计
采用 CardLayout 实现三页切换（欢迎页 → 游戏页 → 结果页），避免多窗口跳转带来的状态同步问题。

核心类职责：

Fraction：封装分数的加减乘除与约分，支持带分数解析
Question：策略模式生成不同难度的题目
GameUI：界面与逻辑解耦，专注事件分发
ArithmeticGame：程序入口
1.3 程序界面
屏幕截图 2026-07-01 205846

屏幕截图 2026-07-01 205925

屏幕截图 2026-07-01 210215

1.4 完整代码
Fraction.java
import java.util.Objects;

/**

• 分数类：支持加减乘除、约分、带分数/假分数转换
  */
  public class Fraction {
  private final int numerator;
  private final int denominator;

  public Fraction(int numerator, int denominator) {
  if (denominator == 0) {
  throw new IllegalArgumentException(“分母不能为零”);
  }
  if (denominator < 0) {
  numerator = -numerator;
  denominator = -denominator;
  }
  int gcd = gcd(Math.abs(numerator), Math.abs(denominator));
  this.numerator = numerator / gcd;
  this.denominator = denominator / gcd;
  }

  public Fraction(int whole) {
  this(whole, 1);
  }

  private int gcd(int a, int b) {
  while (b != 0) {
  int temp = b;
  b = a % b;
  a = temp;
  }
  return a;
  }

  public Fraction add(Fraction other) {
  int num = this.numerator * other.denominator + other.numerator * this.denominator;
  int den = this.denominator * other.denominator;
  return new Fraction(num, den);
  }

  public Fraction subtract(Fraction other) {
  int num = this.numerator * other.denominator - other.numerator * this.denominator;
  int den = this.denominator * other.denominator;
  return new Fraction(num, den);
  }

  public Fraction multiply(Fraction other) {
  return new Fraction(this.numerator * other.numerator, this.denominator * other.denominator);
  }

  public Fraction divide(Fraction other) {
  if (other.numerator == 0) throw new ArithmeticException(“除以零”);
  return new Fraction(this.numerator * other.denominator, this.denominator * other.numerator);
  }

  public double toDouble() {
  return (double) numerator / denominator;
  }

  @Override
  public String toString() {
  if (denominator == 1) return String.valueOf(numerator);
  if (Math.abs(numerator) > denominator) {
  int whole = numerator / denominator;
  int rem = Math.abs(numerator % denominator);
  if (rem == 0) return String.valueOf(whole);
  return whole + “'” + rem + “/” + denominator;
  }
  return numerator + “/” + denominator;
  }

  @Override
  public boolean equals(Object o) {
  if (this == o) return true;
  if (!(o instanceof Fraction)) return false;
  Fraction other = (Fraction) o;
  return this.numerator == other.numerator && this.denominator == other.denominator;
  }

  @Override
  public int hashCode() {
  return Objects.hash(numerator, denominator);
  }

  public int getNumerator() { return numerator; }
  public int getDenominator() { return denominator; }
  }