现在已有一个简单的游戏界面框架，目前程序可以通过ujhk几个键控制主界面上的主角“三角形”“圆形”上下移动。项目结构如下：Scene.java是主类，该类实现了界面的显示，以及对键盘控制的响应。Role类是游戏角色的父类，里面定义了上下左右移动的方法，以及显示该角色的方法。Circle类是一个已经实现了“圆形”角色，它继承了Role类，并且重新Role类里的所有方法。Triangle类是一个已经实现了“三角形”角色，它继承了Role类，并且重新Role类里的所有方法。现在要求扩展新的角色：比如一个小人，一架小车等，即通过继承Role类，重写该类的所有方法，在Scene中用new创建出该类对象就可以实现对新角色的控制！(Now there is a simple game interface framework, and the current program can control the main character "triangle" and "round" on the main interface by ujhk keys. The structure of the project is as follows: Scene.java is the main class, which implements the display of the interface and the response to keyboard control. The Role class is the parent class of the game role, which defines the way of up and down movement and the way to display the role. The Circle class is a circular role that has inherited the Role class and has all the methods in the Role class. The Triangle class is a triangle role that has inherited the Role class and has all the methods in the Role class. It is now required to extend the new role: such as a small man, a small car, and so on, that is, by inheriting the Role class, rewriting all the methods of the class, and creating the class objects in the Scene with new to control the new role!)