简单工厂

1.面向接口编程

public interface IFruit {
    void plant();
    void harvest();
}

public class Grape implements IFruit{
    public void plant(){
        System.out.println("葡萄种植...");
    }
    public void harvest(){
        System.out.println("葡萄收获...");
    }
}

public class Strawberry implements IFruit{
    public void plant(){
        System.out.println("草莓种植...");
    }
    public void harvest(){
        System.out.println("草莓收获...");
    }
}

public class FruitGarden {
    public static  IFruit factory(String which){
        IFruit iFruit = null;
        if (which.equalsIgnoreCase("grape")){
            iFruit = new Grape();
        }
        if (which.equalsIgnoreCase("strawberry")){
            iFruit = new StrawBerry();
        }
        return iFruit;
    }
}

public class Client1 {
    public static void main(String[] args) {
        String[] strings = {"grape","strawberry"};
        for (String str : strings){
            IFruit fruit = FruitGarden.factory(str);
            fruit.plant();
            fruit.harvest();

        }
    }
}

2.简单工厂模式实例

使用java反射改进:

public class FruitGarden {
    public static  IFruit factory(String which) throws ClassNotFoundException, IllegalAccessException, InstantiationException {
        IFruit iFruit = null;
        String pn = FruitGarden.class.getPackage().getName();
        StringBuilder sb = new StringBuilder();
        sb.append(pn);
        sb.append(".");
        sb.append(Character.toUpperCase(which.charAt(0)));
        sb.append(which.substring(1).toLowerCase());
        iFruit = (IFruit)Class.forName(sb.toString()).newInstance();
        return iFruit;
    }
}

public class Client1 {
    public static void main(String[] args) {
        String[] strings = {"grape","strawberry"};
        for (String str : strings){
            IFruit fruit = null;
            try {
                fruit = FruitGarden.factory(str);
                fruit.plant();
                fruit.harvest();
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            } catch (InstantiationException e) {
                e.printStackTrace();
            }
        }
    }
}