package chapter3.demo31; public class Book { private final int id; // 编号 private final String name; // 书名 private final double price; // 价格 private final int storage; // 库存 // 有参构造 public Book(int id, String name, double price, int storage) { this.id = id; this.name = name; this.price = price; this.storage = storage; } // 获取书号 public int getId() { return id; } // 获取书名 public String getName() { return name; } // 获取价格 public double getPrice() { return price; } // 获取库存 public int getStorage() { return storage; } }