工厂模式简单使用

package demo2;
interface Food{
public void eat();
}
class Bread implements Food{
public void eat() {
System.out.println("吃面包");
}
}
class Milk implements Food{
public void eat() {
System.out.println("喝牛奶");
}
}
class Factory{
public Food getInstance(String className) {
if(className.equals("Bread"))
return new Bread();
if(className.equals("Milk"))
return new Milk();
else
return null;
}
}
public class FactoryTest {
public static void main(String[] args) {
Food food1 = new Factory().getInstance("Bread");
food1.eat();
Food food2 = new Factory().getInstance("Milk");
food2.eat();
}

}