此代码是我自己写的，游戏完全基于矢量图形，所有对象都使用计算X和Y 的速率值的算法来移动，每个矢量图形都有一个内建的边界矩形来进行冲突检测-This code can be run under the java virtual machine, the game completely vector-based graphics, all objects are used calculate the rate of X and Y value of the algorithm to move, e