Head First设计模式-抽象工厂模式

最新推荐文章于 2022-06-22 10:16:59 发布

原创最新推荐文章于 2022-06-22 10:16:59 发布 · 1.5k 阅读

0 ·

CC 4.0 BY-SA版权

Java设计模式专栏收录该内容

13 篇文章

订阅专栏

本文介绍了一种设计模式——抽象工厂模式，并通过一个披萨店的例子详细展示了如何使用该模式来创建不同类型的产品。此模式允许系统独立于产品的创建、组合和表示。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

一、整体代码

PizzaStore.java

public  class PizzaStore {
 
	PizzaFactory factory;//多用组合，少用继承  
  
        public PizzaStore(PizzaFactory factory) {  
                this.factory = factory;  
        }  
 
	public Pizza orderPizza(String type) {
		Pizza pizza = factory.createPizza(type);
		System.out.println("--- Making a " + pizza.getName() + " ---");
		pizza.prepare();
		pizza.bake();
		pizza.cut();
		pizza.box();
		return pizza;
	}
}

PizzaFactory.java

interface PizzaFactory{
    Pizza createPizza(String type);
}

NYPizzaFactory.java

public class NYPizzaFactory implements PizzaFactory{
	public Pizza createPizza(String item) {  
        if (item.equals("cheese")) {  
            return new NYStyleCheesePizza();  
        } else if (item.equals("clam")) {  
            return new NYStyleClamPizza();  
        }  else return null;  
    }  
}

ChicagoPizzaFactory.java

public class ChicagoPizzaFactory implements PizzaFactory{
	public Pizza createPizza(String item) {  
            if (item.equals("cheese")) {  
                    return new ChicagoStyleCheesePizza();  
            } else if (item.equals("clam")) {  
                    return new ChicagoStyleClamPizza();  
            }  else return null;  
    	}  
}

Pizza.java


import java.util.ArrayList;

public abstract class Pizza {
	String name;
	String dough;
	String sauce;
	ArrayList toppings = new ArrayList();
 
	void prepare() {
		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 official PizzaStore box");
	}
 
	public String getName() {
		return name;
	}

	public String toString() {
		StringBuffer display = new StringBuffer();
		display.append("---- " + name + " ----\n");
		display.append(dough + "\n");
		display.append(sauce + "\n");
		for (int i = 0; i < toppings.size(); i++) {
			display.append((String )toppings.get(i) + "\n");
		}
		return display.toString();
	}
}

NYStyleClamPizza.java

public class NYStyleClamPizza extends Pizza {

	public NYStyleClamPizza() {
		name = "NY Style Clam Pizza";
		dough = "Thin Crust Dough";
		sauce = "Marinara Sauce";
 
		toppings.add("Grated Reggiano Cheese");
		toppings.add("Fresh Clams from Long Island Sound");
	}
}

NYStyleCheesePizza.java

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");
	}
}

ChicagoStyleClamPizza.java

public class ChicagoStyleClamPizza extends Pizza {
	public ChicagoStyleClamPizza() {
		name = "Chicago Style Clam Pizza";
		dough = "Extra Thick Crust Dough";
		sauce = "Plum Tomato Sauce";
 
		toppings.add("Shredded Mozzarella Cheese");
		toppings.add("Frozen Clams from Chesapeake Bay");
	}
 
	void cut() {
		System.out.println("Cutting the pizza into square slices");
	}
}

ChicagoStyleCheesePizza.java

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");
	}
}

PizzaTestDrive.java

public class PizzaTestDrive {
 
	public static void main(String[] args) {
		PizzaFactory factory = new NYPizzaFactory();  
                PizzaStore store = new PizzaStore(factory);  
  
                Pizza pizza = store.orderPizza("cheese");  
                System.out.println("We ordered a " + pizza.getName() + "\n");  
  
                pizza = store.orderPizza("clam");  
                System.out.println("We ordered a " + pizza.getName() + "\n");  

		PizzaFactory factory1 = new ChicagoPizzaFactory();  
                PizzaStore store1 = new PizzaStore(factory);  
  
                Pizza pizza1 = store1.orderPizza("cheese");  
                System.out.println("We ordered a " + pizza.getName() + "\n");  
  
                pizza1 = store1.orderPizza("clam");  
                System.out.println("We ordered a " + pizza.getName() + "\n");  

	}
}

二、解释

抽象工厂模式：提供了一个接口，用来创建相关和依赖对象的家族，而不需要明确指名具体类。