简单工厂模式(一)

总述

其实这篇博客说的是静态工厂模式，它是简单工厂模式的一种。

类图

工厂模式.png

实现

调用

package com.company;

public class Main {

    public static void main(String[] args) {
    // write your code here
        try {
            Product one = Factory.productProducer(ProductA.class.toString());
            one.printProductInformation();

            Product two = Factory.productProducer(ProductB.class.toString());
            two.printProductInformation();

            Product three = Factory.productProducer(Product.class.toString());
            three.printProductInformation();
        } catch (NullPointerException e) {
            System.out.println(e.toString());
        }
    }
}

输出

这是A产品
这是B产品
java.lang.NullPointerException: 无法生产此种产品

Process finished with exit code 0

工厂

package com.company;

public class Factory {
    public static Product productProducer(String type) {
        if (type.equals(ProductA.class.toString())) {
            return new ProductA();
        } else if (type.equals(ProductB.class.toString())) {
            return new ProductB();
        } else {
            throw new NullPointerException("无法生产此种产品");
        }
    }
}

产品接口

package com.company;

public interface Product {
    void printProductInformation();
}

A产品

package com.company;

public class ProductA implements Product {
    @Override
    public void printProductInformation() {
        System.out.println("这是A产品");
    }
}

B产品

package com.company;

public class ProductB implements Product {
    @Override
    public void printProductInformation() {
        System.out.println("这是B产品");
    }
}

返回