文档介绍：.*;.*;.*;lassDrawCircleextendsJFrameimplementsActionListener{privateJButtonbutton;privateJPanelpanel;publicstaticvoidmain(String[]args){DrawCircleframe=newDrawCircle();(400,300);();();}privatevoidcreateGUI(){setDefaultCloseOperation(EXIT_ON_CLOSE);Containerwindow=getContentPane();(newFlowLayout());panel=newJPanel();(newDimension(300,200));();(panel);button=newJButton("pressme");(button);(this);}publicvoidactionPerformed(ActionEventevent){Graphicspaper=();(0,0,100,100);}}.*;lasszhengshu{publicstaticvoidmain(Stringargs[]){Scannerreader=newScanner();intqiuzheng=0;doublexiaoshu;while(()){doublex=();xiaoshu=x-(int)x;if(xiaoshu<)qiuzheng=(int)x;elseqiuzheng=(int)(x+);}("四舍五入后取整得%d\n",qiuzheng);}}ount{privatedoublebalance=0;publicdoublegetBalance(){returnbalance;}publicstaticvoidmain(String[]args){doublebalance=;Accounta=ount();();("类成员访问例题:%f",balance);}}13页classA{voidf(){("Goodmoring");}}lassGoodmoring{publicstaticvoidmain(Stringargs[]){("早上好,");Aa=newA();();}};lassqiuji