Java 设计模式之Factory method Pattern

abstract class Product{
    public abstract void use();
}

abstract class Factory{
    public final Product create(String owner){
        Product p = createProduct(owner);
        registerProduct(p);
        return p;
    }
    protected abstract Product createProduct(String owner);
    protected abstract void registerProduct(Product product);
}

class IDCard extends Product{
    private String owner;
    public IDCard(String owner) {
        System.out.println("Create " + owner + "/' card.");
        this.owner = owner;
    }
    public void use(){
        System.out.println("Use " + owner + "/' card.");
    }
    public String getOwner(){
        return owner;
    }
}

class IDCardFactory extends Factory{
    private Vector owners = new Vector();
    protected Product createProduct(String owner){
        return new IDCard(owner);
    }
    @Override
    protected void registerProduct(Product product) {       
        owners.add(((IDCard)product).getOwner());
    }
    public Vector getOwners(){
        return owners;
    }
}

public class FactoryPatten {
    public static void main(String[] args) {
        Factory factory = new IDCardFactory();
        Product card1 = factory.create("Zhange san");
        Product card2 = factory.create("Li shi");
        Product card3 = factory.create("Wang wu");
        card1.use();
        card2.use();
        card3.use();
    }
}