java程式設計建立型設計模式工廠方法模式範例詳解

package com.szh.factory.factorymethod.pizza;
/**
 * 宣告Pizza類為抽象類
 */
public abstract class Pizza {
    //Pizza名稱
    protected String name;
    //準備原材料，不同的披薩不一樣。因此，我們做成抽象方法，具體的原材料實現交給它的子類去完成
    public abstract void prepare();
    //烘烤
    public void bake() {
        System.out.println(name + " baking;");
    }
    //切割
    public void cut() {
        System.out.println(name + " cutting;");
    }
    //打包
    public void box() {
        System.out.println(name + " boxing;");
    }
    public void setName(String name) {
        this.name = name;
    }
}

package com.szh.factory.factorymethod.pizza;
public class BJCheesePizza extends Pizza {
	@Override
	public void prepare() {
		setName("北京的乳酪pizza");
		System.out.println("北京的乳酪pizza 準備原材料");
	}
 
}

package com.szh.factory.factorymethod.pizza;
public class BJPepperPizza extends Pizza {
	@Override
	public void prepare() {
		setName("北京的胡椒pizza");
		System.out.println("北京的胡椒pizza 準備原材料");
	}
 
}

package com.szh.factory.factorymethod.pizza;
public class LDCheesePizza extends Pizza{
	@Override
	public void prepare() {
		setName("倫敦的乳酪pizza");
		System.out.println("倫敦的乳酪pizza 準備原材料");
	}
 
}

package com.szh.factory.factorymethod.pizza;
public class LDPepperPizza extends Pizza{
 	@Override
	public void prepare() {
		setName("倫敦的胡椒pizza");
		System.out.println("倫敦的胡椒pizza 準備原材料");
	}
 
}

package com.szh.factory.factorymethod.order;
import com.szh.factory.factorymethod.pizza.Pizza;
import java.util.Scanner;
public abstract class OrderPizza {
    //定義一個抽象方法, createPizza, 讓各個工廠子類自己實現
    abstract Pizza createPizza(String orderType);
    public OrderPizza() {
        Pizza pizza = null;
        String orderType = "";
        do {
            orderType = getType();
            pizza = createPizza(orderType); //抽象方法, 由工廠子類完成
            // 輸出pizza 製作過程
            pizza.prepare();
            pizza.bake();
            pizza.cut();
            pizza.box();
        } while (true);
    }
    private String getType() {
        Scanner scanner = new Scanner(System.in);
        System.out.println("請輸入 pizza 種類: ");
        String str = scanner.nextLine();
        return str;
    }
}

package com.szh.factory.factorymethod.order;
import com.szh.factory.factorymethod.pizza.BJCheesePizza;
import com.szh.factory.factorymethod.pizza.BJPepperPizza;
import com.szh.factory.factorymethod.pizza.Pizza;
public class BJOrderPizza extends OrderPizza {
    @Override
    Pizza createPizza(String orderType) {
        Pizza pizza = null;
        if (orderType.equals("cheese")) {
            pizza = new BJCheesePizza();
        } else if (orderType.equals("pepper")) {
            pizza = new BJPepperPizza();
        } else {
            throw new NullPointerException("暫無該Pizza種類....");
        }
        return pizza;
    }
 
}

package com.szh.factory.factorymethod.order;
import com.szh.factory.factorymethod.pizza.*;
public class LDOrderPizza extends OrderPizza {
    @Override
    Pizza createPizza(String orderType) {
        Pizza pizza = null;
        if (orderType.equals("cheese")) {
            pizza = new LDCheesePizza();
        } else if (orderType.equals("pepper")) {
            pizza = new LDPepperPizza();
        } else {
            throw new NullPointerException("暫無該Pizza種類....");
        }
        return pizza;
    }
}

package com.szh.factory.factorymethod;
import com.szh.factory.factorymethod.order.BJOrderPizza;
import com.szh.factory.factorymethod.order.LDOrderPizza;
import java.util.Scanner;
public class MainTest {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String content = scanner.next();
        if (content.equals("Beijing")) {
            new BJOrderPizza();
        } else if (content.equals("London")) {
            new LDOrderPizza();
        } else {
            System.out.println("無法預先匹配Pizza種類....");
            scanner.close();
        }
    }
}