java 编写的简单计算器

package a1; import javax.swing.*; import java.awt.*; import java.awt.event.*; class MyWindow extends JFrame implements ActionListener { String s="",s1; double x,y;//x和y都是运算数 Container contentPane; JMenuBar menubar; JMenu menu1,menu2; JMenuItem item1,item2,item3; JPanel pane; Box Hede1,Hede2,Hede3,Hede4,Vede,bosde; Button but1,but2,but3,but4,but5,but6; JTextField num1,num2,rus; Container con; MyWindow(String s) { super(s); setSize(320,300); setLocation(120,120); setVisible(true); menubar=new JMenuBar(); menu1=new JMenu("工具箱"); menu2=new JMenu("版本说明"); item1=new JMenuItem("计算器"); item2=new JMenuItem("日历"); item3=new JMenuItem("记事本"); pane= new JPanel(); item1.addActionListener(this); item1.setAccelerator(KeyStroke.getKeyStroke('C')); item2.setAccelerator(KeyStroke.getKeyStroke('R')); item3.setAccelerator(KeyStroke.getKeyStroke('N')); menu1.add(item1); menu1.addSeparator(); menu1.add(item2); menu1.addSeparator(); menu1.add(item3); menubar.add(menu1); menubar.add(menu2); setJMenuBar(menubar); //设置BoxLayout布局 Hede1=Box.createHorizontalBox(); Vede=Box.createVerticalBox(); Vede.add(new JLabel("请输入要计算的数字")); Vede.add(Box.createVerticalStrut(10)); num1=new JTextField(); Hede1.add(new JLabel("num1")); Hede1.add(num1); num2=new JTextField(); Hede1.add(new JLabel("num2")); Hede1.add(num2); Vede.add(Hede1); Vede.add(Box.createVerticalStrut(10)); Hede2=Box.createHorizontalBox(); but1=new Button("+"); but2=new Button("-"); but3=new Button("*"); but4=new Button("%"); Hede2.add(but1); Hede2.add(but2); Hede2.add(but3); Hede2.add(but4); Vede.add(Hede2); Vede.add(Box.createVerticalStrut(10)); Hede3=Box.createHorizontalBox(); Hede3.add(new JLabel("结果")); rus=new JTextField(); Hede3.add(rus); Vede.add(Hede3); Vede.add(Box.createVerticalStrut(10)); Hede4=Box.createHorizontalBox(); but5=new Button("重置"); but6=new Button("关闭"); Hede4.add(but5); Hede4.add(but6); Vede.add(Hede4); but1.addActionListener(this); but2.addActionListener(this); but3.addActionListener(this); but4.addActionListener(this); but5.addActionListener(this); but6.addActionListener(this); //把计算器中的组件加到面板容器pane pane.add(Vede); //获取内容面板 contentPane = getContentPane(); validate(); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); } public void actionPerformed(ActionEvent e) { if(e.getSource()==item1) { //添加面板容器到窗体的内容面板 contentPane.add(pane); validate(); contentPane.repaint();//界面刷新 } else if(e.getSource()==but6) { //从内容面板移除面板容器 contentPane.remove(pane); validate(); contentPane.repaint();//界面刷新 } try { if(e.getSource()==but1) { x=Double.parseDouble(num1.getText().trim()); y=Double.parseDouble(num2.getText().trim()); rus.setText(""+(x+y)); } else if(e.getSource()==but2) { x=Double.parseDouble(num1.getText().trim()); y=Double.parseDouble(num2.getText().trim()); rus.setText(""+(x-y)); } else if(e.getSource()==but3) { x=Double.parseDouble(num1.getText().trim()); y=Double.parseDouble(num2.getText().trim()); rus.setText(""+(x*y)); } else if(e.getSource()==but4) { x=Double.parseDouble(num1.getText().trim()); y=Double.parseDouble(num2.getText().trim()); rus.setText(""+(x/y)); if(y==0) { rus.setText("除数不能为零"); } } else if (e.getSource()==but5) { num1.setText(""); num2.setText(""); rus.setText("0"); } } catch(NumberFormatException e1) { rus.setText("数字格式异常"); } catch(StringIndexOutOfBoundsException e1) { rus.setText("字符串索引越界"); } } } public class testZ { public static void main(String args[]) { new MyWindow("我的工具箱"); } }