工厂模式案例

以你之姓@ 2022-06-18 09:12 73阅读 0赞

工厂方法模式：定义了一个创建对象的接口，但由子类决定要实例化的类是哪一个、

工厂方法让类把实例化推迟到子类。

import java.util.ArrayList;

/\*  
 \* 抽象披萨类，所有的具体 披萨类都必须派生自这个类  
 \*/  
public abstract class Pizza \{  
    String name;  
    String dough;  
    String sauce;  
    ArrayList<String> toppings=new ArrayList<>();  
    void perpare()\{  
        System.out.println("Preparing "+name);  
        System.out.println("Tossing dough...");  
        System.out.println("Adding sauce...");  
        System.out.println("Adding toppings: ");  
        for(int i=0;i<toppings.size();i++)\{  
            System.out.println("  "+toppings.get(i));  
        \}  
    \}  
    void bake()\{  
        System.out.println("Bake for 25 minutes at 350");  
    \}  
    void cut()\{  
        System.out.println("Cutting the pizza into diagonal slices");  
    \}  
    void box()\{  
        System.out.println("Place pizza in fooicial PizzaStore box");  
    \}  
    public String getName()\{  
        return name;  
    \}

public class NYStylePizzaStore extends PizzaStore\{  
  
    @Override  
    Pizza createPizza(String type) \{  
        // TODO Auto-generated method stub  
        Pizza pizza=null;  
        if(type.equals("cheese"))\{  
            pizza=new NYStyleCheesePizza();  
            return pizza;  
        \}  
        return null;  
    \}  
  
\}

public class NYStyleCheesePizza extends Pizza\{  
    public NYStyleCheesePizza()\{  
        name="NY Style Sauce and Cheese Pizza";  
        dough="Thin Crust Dough";  
        sauce="Marinara Sauce";  
        toppings.add("Grated Reggiano Cheese");  
    \}  
\}

public abstract class PizzaStore \{  
    public Pizza orderPizza(String type)\{  
        Pizza pizza;  
        pizza =createPizza(type);  
        pizza.perpare();  
        pizza.bake();  
        pizza.cut();  
        pizza.box();  
        return pizza;  
    \}  
    abstract Pizza createPizza(String type);  
\}

public class ChicagoStylePizzaStore extends PizzaStore\{  
  
    @Override  
    Pizza createPizza(String type) \{  
        // TODO Auto-generated method stub  
        Pizza pizza=null;  
        if(type.equals("cheese"))\{  
            pizza=new ChicagoStyleCheesePizza();  
            return pizza;  
        \}  
        return null;  
    \}  
  
\}

public class ChicagoStyleCheesePizza extends Pizza\{  
    public ChicagoStyleCheesePizza()\{  
        name="Chicago Style Deep Dish Cheese Pizza";  
        dough="Extra Thick Crust Dough";  
        sauce="Plum Tomato Sauce";  
        toppings.add("Shredded Mozzarella Cheese");  
    \}  
    void cut()\{  
        System.out.println("Cutting the pizza into square slices");  
    \}  
\}  
  
测试：

public class PizzaTest \{  
  
    public static void main(String\[\] args) \{  
        // TODO Auto-generated method stub  
        PizzaStore nyStore=new NYStylePizzaStore();  
        PizzaStore chicagoStore=new ChicagoStylePizzaStore();  
        Pizza pizza=nyStore.orderPizza("cheese");  
        System.out.println("Ethan ordered a "+pizza.getName()+"\\n");  
        pizza=chicagoStore.orderPizza("cheese");  
        System.out.println("Joel ordered a "+pizza.getName()+"\\n");  
    \}  
  
\}

效果：

Preparing NY Style Sauce and Cheese Pizza  
Tossing dough...  
Adding sauce...  
Adding toppings:  
  Grated Reggiano Cheese  
Bake for 25 minutes at 350  
Cutting the pizza into diagonal slices  
Place pizza in fooicial PizzaStore box  
Ethan ordered a NY Style Sauce and Cheese Pizza  
  
Preparing Chicago Style Deep Dish Cheese Pizza  
Tossing dough...  
Adding sauce...  
Adding toppings:  
  Shredded Mozzarella Cheese  
Bake for 25 minutes at 350  
Cutting the pizza into square slices  
Place pizza in fooicial PizzaStore box  
Joel ordered a Chicago Style Deep Dish Cheese Pizza