interface FruitInterface {
  void eat();
}

class Apple implements FruitInterface{

  @Override
  public void eat() {
    // TODO Auto-generated method stub
    System.out.println("吃苹果");
  }

}

public class Orange implements FruitInterface{

  @Override
  public void eat() {
    // TODO Auto-generated method stub
    System.out.println("吃橘子");
  }

}

public class Factory {
  //定义工厂类
public static FruitInterface getInstance(String className){
  FruitInterface fruit = null;
    
  if ("Apple".equals(className)) {//将字符串放在前面可以避免空值
    fruit = new Apple();
  } if ("Orange".equals(className)) {
    fruit = new Orange();
  }    
    
  return fruit;
    
}
}
public class FirstDemo {

  /**
    * 工厂设计模式
    */
  public static void main(String[] args) {
    FruitInterface fruitInterface = Factory.getInstance("Apple");
    fruitInterface.eat();
    FruitInterface fruitInterface2 = Factory.getInstance("Orange");
    fruitInterface2.eat();

  }
}