1.电器类 一个电器销售公司想开发一套管理系統，该公司的主要业务是销售一些家用电器，倒如：电冰箱、洗衣机、电視机产品。 经调查，各种电器的属性如下： 冰箱类：品牌、型号、颜色、售价、门款式、制冷方式。 洗衣机美：品牌、型号、颜色、售价、电机类型、洗涤容量。 电視类：品牌、型号、颜色、售价、屏幕尺寸、分辦率。 不同的电器有不同的显示信息的方式。 要求：用封装、继承（包括this、super等） 等知识点编程实现。

以下是一个基于Java语言的电器销售公司管理系统的代码示例，其中使用了封装和继承等知识点：

// 定义电器类
public class ElectricalAppliance {
    private String brand; // 品牌
    private String model; // 型号
    private String color; // 颜色
    private double price; // 售价

    public ElectricalAppliance(String brand, String model, String color, double price) {
        this.brand = brand;
        this.model = model;
        this.color = color;
        this.price = price;
    }

    // getter和setter方法
    public String getBrand() {
        return brand;
    }

    public void setBrand(String brand) {
        this.brand = brand;
    }

    public String getModel() {
        return model;
    }

    public void setModel(String model) {
        this.model = model;
    }

    public String getColor() {
        return color;
    }

    public void setColor(String color) {
        this.color = color;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }
}

// 定义冰箱类
public class Refrigerator extends ElectricalAppliance {
    private String doorStyle; // 门款式
    private String coolingMethod; // 制冷方式

    public Refrigerator(String brand, String model, String color, double price, String doorStyle, String coolingMethod) {
        super(brand, model, color, price);
        this.doorStyle = doorStyle;
        this.coolingMethod = coolingMethod;
    }

    // getter和setter方法
    public String getDoorStyle() {
        return doorStyle;
    }

    public void setDoorStyle(String doorStyle) {
        this.doorStyle = doorStyle;
    }

    public String getCoolingMethod() {
        return coolingMethod;
    }

    public void setCoolingMethod(String coolingMethod) {
        this.coolingMethod = coolingMethod;
    }
}

// 定义洗衣机类
public class WashingMachine extends ElectricalAppliance {
    private String motorType; // 电机类型
    private int washingCapacity; // 洗涤容量

    public WashingMachine(String brand, String model, String color, double price, String motorType, int washingCapacity) {
        super(brand, model, color, price);
        this.motorType = motorType;
        this.washingCapacity = washingCapacity;
    }

    // getter和setter方法
    public String getMotorType() {
        return motorType;
    }

    public void setMotorType(String motorType) {
        this.motorType = motorType;
    }

    public int getWashingCapacity() {
        return washingCapacity;
    }

    public void setWashingCapacity(int washingCapacity) {
        this.washingCapacity = washingCapacity;
    }
}

// 定义电视类
public class Television extends ElectricalAppliance {
    private int screenSize; // 屏幕尺寸
    private String resolution; // 分辦率

    public Television(String brand, String model, String color, double price, int screenSize, String resolution) {
        super(brand, model, color, price);
        this.screenSize = screenSize;
        this.resolution = resolution;
    }

    // getter和setter方法
    public int getScreenSize() {
        return screenSize;
    }

    public void setScreenSize(int screenSize) {
        this.screenSize = screenSize;
    }

    public String getResolution() {
        return resolution;
    }

    public void setResolution(String resolution) {
        this.resolution = resolution;
    }
}

// 定义电器销售公司管理系统类
public class ElectricalApplianceManagementSystem {
    public static void main(String[] args) {
        Refrigerator r = new Refrigerator("Haier", "BCD-123", "White", 1999.99, "Double Door", "Direct Cooling");
        System.out.println(r.getBrand() + " " + r.getModel() + " " + r.getColor() + " " + r.getPrice() + " " + r.getDoorStyle() + " " + r.getCoolingMethod());

        WashingMachine w = new WashingMachine("LG", "WTG8520", "Silver", 2999.99, "Inverter Motor", 8);
        System.out.println(w.getBrand() + " " + w.getModel() + " " + w.getColor() + " " + w.getPrice() + " " + w.getMotorType() + " " + w.getWashingCapacity());

        Television t = new Television("Samsung", "UA55RU7100", "Black", 4999.99, 55, "3840x2160");
        System.out.println(t.getBrand() + " " + t.getModel() + " " + t.getColor() + " " + t.getPrice() + " " + t.getScreenSize() + " " + t.getResolution());
    }
}

以上代码示例中，`ElectricalAppliance`类是所有电器的基类，`Refrigerator`、`WashingMachine`和`Television`类都继承自`ElectricalAppliance`类，并且添加了各自特有的属性和方法。在`ElectricalApplianceManagementSystem`类中，我们创建了一个冰箱对象、一个洗衣机对象和一个电视对象，并打印出它们的属性。