题目内容：

英语翻译
The scattering program requires the Scatter,ScatterAnalysis,and ScatterApp
classes.The ScatterApp class in Listing 5.6 organizes the startup process and creates the visualizations.As usual,it extends AbstractSimul ati on by overriding the doStep method.However,in this case a single step is not a time step.A step calculates a trajectory and scattering angle for the given impact parameter.After a trajectory is calculated,the impact parameter is incremented and the panel is repainted.If necessary,you can eliminate this visualization to increase the computational speed.If the new impact parameter exceeds the beam radius bmax,the animation is stopped and the accumulated data is analyzed.Note that the cal cul ateTrajectory method returns true if the calculation succeeded and that an error message is printed if the calculation fails.Including a failsafe mechanism to stop a computation is good programming practice.
人工翻译，谷歌翻译的错误太多！

优质解答

散射程序要求散射开ScatterAnalysis和ScatterApp类程序6中的ScatterApp类系统化启动步骤并且创建可视化.它用最重要的doStep方法继承抽象模拟.可是,在这种情况下,单一的步骤不是一个时间间隔.一个步骤计算轨道和碰撞系数得出的散射角.但轨道被计算出来后,碰撞系数在增加并且面板被重新绘制.如果需要,你可以消除可视化来增加计算速度.如果新的碰撞系数超过了最大束半径,动画停止并且分析积累的数据.注意,如果计算成功,calculateTrajectory方法返回true,如果计算失败,一条错误的消息显示出来.包含一个故障防护机制去停止计算是一个很好的程序编制习惯.