Java8之工厂模式

interface Number {

}

class One implements Number {

}

class Two implements Number {

}

class Three implements Number {

}

class NumberFactory {
    final static Map<String, Supplier<Number>> map = new HashMap<>();

    static {
        map.put("one", One::new);
        map.put("two", Two::new);
        map.put("three", Three::new);
    }

    public static Number createNumber(String number) {
        Supplier<Number> numberSupplier = map.get(number);
        if (numberSupplier != null) return numberSupplier.get();
        throw new IllegalArgumentException("No such product " + number);
    }
}

public class Main {
    public static void main(String[] args) {
        Number number = NumberFactory.createNumber("one");
        Number number1 = NumberFactory.createNumber("two");
        System.out.println(number.getClass());
        System.out.println(number1.getClass());
    }
}