出的小妹啊啊啊

目录

1 系统设计与建模

 2 开闭原则

3.组合模式

4 工厂方法

5.代码重构

1 系统设计与建模

用例ID	UC1
用例名称	处理销售
场景	顾客选定欲购买的商品并到收银台计价结账
触发事件	收银员开始一次新的销售交易
简要描述	顾客携带所购商品到收银台，收银员计价和收款，并打印票据
参与者	收银员
相关用例	处理退货、收款
关联人员	售货员、顾客、经理
前置条件	收银员经过确认和认证
后置条件	存储销售信息，准确计算税金，更新账务和库存信息，记录提成，生成票据，记录支付授权的批准
活动流	参与者	系统
	1.收银员开始一次新的销售交易 2.收银员输入商品条码 3.收银员告知顾客总额，并请顾客付款，顾客付款 4.收银员把票据交给顾客	2.1.系统逐条记录出售的商品 2.2.系统显示商品描述、价格和累计额 2.3.系统显示总额和税金 3.1.系统记录完整的销售信息 3.2.系统将销售和支付信息发送到外部的账务系统和库存系统 3.3.系统打印票据
异常情形	... ...

 

 

 

 2 开闭原则

public class Apple extends Fruit {

    public Apple(Integer id, String name, Double price) {
        super(id, name, price);
    }

    public Double getPromotionPrice() {
        return getPrice() * getDiscount();
    }

}

public class Client {
    public static void main(String[] args) {
        Fruit fruit = new Apple(1, "苹果", 20.0);
        fruit.setDiscount(0.8);
        printInfo(fruit);
    }

    public static void printInfo(Fruit fruit) {
        System.out.println("Id: " + fruit.getId() + "; 名称: " + fruit.getName() + "; 原价格: " + fruit.getPrice());
        System.out.println("促销价格: " + fruit.getPromotionPrice());
    }
}

public abstract class Fruit {
    private Integer id;
    private String name;
    private Double price;
    private Double discount;

    public Fruit(Integer id, String name, Double price) {
        this.id = id;
        this.name = name;
        this.price = price;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Double getPrice() {
        return price;
    }

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

    public Double getDiscount() {
        return discount;
    }

    public void setDiscount(Double discount) {
        this.discount = discount;
    }

    public abstract Double getPromotionPrice();

}

public class Banana extends Fruit {

    public Banana(Integer id, String name, Double price) {
        super(id, name, price);
    }

    public Double getPromotionPrice() {
        return getPrice() * getDiscount();
    }

}

3.组合模式

public class DemoLab {
    public static void main(String[] args) {
        // 构建公司的组织结构
        Department rootDepartment = new Department(1001);
        Department saleDepartment = new Department(100101);
        Department financialDepartment = new Department(100102);

        Employee zhangsan = new Employee(1, 10000);
        Employee lisi = new Employee(2, 5000);
        Employee wangwu = new Employee(3, 3000);
        Employee zhaoliu = new Employee(4, 4000);

        rootDepartment.addSubNode(saleDepartment);
        rootDepartment.addSubNode(financialDepartment);
        rootDepartment.addSubNode(zhangsan);
        saleDepartment.addSubNode(lisi);
        financialDepartment.addSubNode(wangwu);
        financialDepartment.addSubNode(zhaoliu);

        // 计算财务部的薪资成本
        System.out.println("部门：" + financialDepartment.id);
        System.out.println("薪资成本：" + financialDepartment.calculateSalary());
    }
}

import java.util.ArrayList;
import java.util.List;

public class Department extends HumanResource {
    private List subNodes = new ArrayList<>();

    public Department(long id) {
        super(id);
    }

    @Override
    public double calculateSalary() {
        double totalSalary = 0;
        for (HumanResource hr : subNodes) {
            totalSalary += hr.calculateSalary();
        }
        this.salary = totalSalary;
        return totalSalary;
    }

    public void addSubNode(HumanResource hr) {
        subNodes.add(hr);
    }
}

public class Employee extends HumanResource {
    public Employee(long id, double salary) {
        super(id);
        this.salary = salary;
    }

    @Override
    public double calculateSalary() {
        return salary;
    }
}

public abstract class HumanResource {
    protected long id;
    protected double salary;

    public HumanResource(long id) {
        this.id = id;
    }

    public long getId() {
        return id;
    }

    public abstract double calculateSalary();
}

4 工厂方法

1

请根据下面的要求用工厂方法模式进行设计。

设计一个程序用于读取多种不同格式的图片文件，对每种不同的图片格式都设计一个图片读取器（ImageReader），例如：PNG图片读取器（PngReader）；JPG图片读取器（JpgReader）。图片读取器对象通过图片读取器工厂（ImageReaderFactory）创建，ImageReaderFactory是一个抽象类，用于定义创建图片读取器的工厂方法，其具体子类（PngReaderFactory，JpgReaderFactory）用于创建具体的图片读取器对象。

【提示：图片读取器是“产品”，图片读取器工厂是“工厂”，它们均有抽象的和具体的；工厂和产品是对应的，即什么工厂就生产什么产品。】.

public interface ImageReaderFactory {
   public ImageReader createImageReader();
}

public class JpgReader implements ImageReader {
   public void readImage() {
      System.out.println("正在阅读JPG格式的图片......");
   }
}

public class JpgReaderFactory implements ImageReaderFactory {
   public ImageReader createImageReader() {
      System.out.println("JPG图片阅读器工厂生产JPG图片阅读器......完成");
      return new JpgReader();
   }
}

public class PngReader implements ImageReader {
   public void readImage() {
      System.out.println("正在阅读PNG格式的图片......");
   }
}

public class PngReaderFactory implements ImageReaderFactory {
   public ImageReader createImageReader() {
      System.out.println("PNG图片阅读器工厂生产PNG图片阅读器......完成");
      return new PngReader();
   }
}

public class ClientFM {
   public static void main(String args[]) {
      ImageReader reader;
      ImageReaderFactory factory;
      factory = new PngReaderFactory();
      reader = factory.createImageReader();
      reader.readImage();
   }
}

5.代码重构

function printOwing(invoice) {

    printBanner()

    const outstanding = caculateOutstanding(invoice)

    recordDueDate(invoice)

    printDetails(invoice, outstanding)

}

function printBanner() {

    console.log("***********************")

    console.log("**** Customer Owes ****")

    console.log("***********************")

}

function caculateOutstanding(invoice) {

    let result = 0;

    for (const o of invoice.orders) {

        result += o.amount

    }

    return result

}

function recordDueDate(invoice) {

    const today = Clock.today;

    invoice.dueDate = new Date(today.getFullYear(), today.getMonth(), today.getDate() + 30)

}

function printDetails(invoice, outstanding) {

    console.log(`name: ${invoice.customer}`)

    console.log(`amount: ${outstanding}`)

    console.log(`name: ${invoice.dueDate.toLocaleDateString()}`)

}