java实验报告-简单计算器的编写

-.z.JAVA实验报告——简单计算器的编写班级：**：：一、实验目的1.掌握java图形用户界面（GUI)的设计原理和程序结构2.能设计复核问题要求的图形用户界面程序3.掌握常用组件的事件接口

4.应用awt和swing组件进行应用程序设计二、实验条件1.计算机一台2.java软件开发环境三、实验步骤1、编写代码：mportjava.awt.*;importjava.awt.event.*;importjava*.swing.*;publicclassJCalculatore*tendsJFrameimplementsActionListener{privatestaticfinallongserialVersionUID=-7LprivateclassWindowClosere*tendsWindowAdapter{publicvoidwindowClosing(WindowEventwe){System.e*it(0);}}inti;privatefinalString[]str={"7","8","9","/","4","5","6","*","1","2","3","-",".","0","=","+"};utton[]buttons=newutton[str.length];uttonreset=newutton("CE");JTe*tFielddisplay=newJTe*tField("0");publicJCalculator(){super("Calculator");JPanelpanel1=newJPanel(newGridLayout(4,4));for(i=0;i<str.length;i++){buttons[i]=newutton(str[i]);panel1.add(buttons[i]);}JPanelpanel2=newJPanel(newBorderLayout());panel2.add("Center",display);panel2.add("East",reset);getContentPane().setLayout(newBorderLayout());getContentPane().add("North",panel2);getContentPane().add("Center",panel1);for(i=0;i<str.length;i++)buttons[i].addActionListener(this);reset.addActionListener(this);display.addActionListener(this);addWindowListener(newWindowCloser());setSize(800,800);setVisible(true);pack();}publicvoidactionPerformed(ActionEvente){Objecttarget=e.getSource();Stringlabel=e.getActionmand();if(target==reset)handleReset();elseif("0123456789.".inde*Of(label)>0)handleNumber(label);elsehandleOperator(label);}booleanisFirstDigit=true;publicvoidhandleNumber(Stringkey){if(isFirstDigit)display.setTe*t(key);elseif((key.equals("."))&&(display.getTe*t().inde*Of(".")<0))display.setTe*t(display.getTe*t()+".");elseif(!key.equals("."))display.setTe*t(display.getTe*t()+key);isFirstDigit=false;}publicvoidhandleReset(){display.setTe*t("0");isFirstDigit=true;operator="=";}doublenumber=0.0;Stringoperator="=";publicvoidhandleOperator(Stringkey){if(operator.equals("+"))number+=Double.valueOf(display.getTe*t());elseif(operator.equals("-"))number-=Double.valueOf(display.getTe*t());elseif(operator.equals("*"))number*=Double.valueOf(display.getTe*t());elseif(operator.equals("/"))number/=Double.valueOf(display.getTe*t());elseif(operator.equals("="))number=Double.valueOf(display.getTe*t());display.setTe*t(String.valueOf(number));operator=key;isFirstDigit=true;}publicstaticvoidmain(String[]args){newJCalculator();}}2、运行结果，见截图计算测试：123+456=579结果正确，程序无误。计算测试：10*10*10=1000，结果正确，程序无误。四、实验总结通过对计算器窗体的编写我熟悉java图形用户界面的设计原理和程序结构熟悉java