import javax.swing.*;import java.awt.event.*;import java.awt.*;import ng.Math;class ring extends JFrame implements ActionListener{//定义成员变量：//JFrame frame;//定义一个窗口类；JTextField text;//定义一个文本框类；JLabel label;//定义一个标签类；JPanel p1,p2,p3,p4,p5,p6;//定义面板类；String s1,s,s2;//定义三个字符串变量；int count=0;JButtona1,a2,a3,a4,a5,a6,b1,b2,b3,b4,b5,b6,c1,c2,c3,c4,c5,c6,d1,d2,d3,d4 ,d5,d6;//ring的构造函数；ring(){this.setTitle("计算器");// super("计算器");JMenuBar menubar1=new JMenuBar();//新建菜单条；this.setJMenuBar(menubar1);JMenu menu1=new JMenu("编辑(E)");JMenu menu2=new JMenu("查看(V)");JMenu menu3=new JMenu("帮助(H)");menubar1.add(menu1);menubar1.add(menu2);menubar1.add(menu3);JMenuItem item1=new JMenuItem("复制(c) ctrl+c");JMenuItem item2=new JMenuItem("粘贴(p) ctrl+v");JMenuItem item3=new JMenuItem("标准型(T)");JMenuItem item4=new JMenuItem("科学型(s)");JMenuItem item5=new JMenuItem("数字分组(I)");JMenuItem item6=new JMenuItem("帮助主题(H)");JMenuItem item7=new JMenuItem("关于计算机(A)");menu1.add(item1);menu1.add(item2);menu2.add(item3);menu2.add(item4);menu2.add(item5);menu3.add(item6);menu3.add(item7);this.show();this.setBounds(100,100,500,100);this.setVisible(true);p1=new JPanel();//新建面板对象；label=new JLabel("计算结果");//新建一个“计算结果”的标签；text=new JTextField(25);//定义25字符的文档框；text.setEditable(false);text.setHorizontalAlignment(JTextField.LEFT);//定义水平左对齐；p1.add(label);//将标签label添加到面板p1中；p1.add(text);//将文本框text添加到面板p1中；a1=new JButton("Backspace");a2=new JButton("7");a3=new JButton("8");a4=new JButton("9");a5=new JButton("/");a6=new JButton("sqrt");b1=new JButton("MR");b2=new JButton("4");b3=new JButton("5");b4=new JButton("6");b5=new JButton("*");b6=new JButton("%");c1=new JButton("MS");c2=new JButton("1");c3=new JButton("2");c4=new JButton("3");c5=new JButton("-");c6=new JButton("1/x");d1=new JButton("M+");d2=new JButton("0");d3=new JButton("+/-");d4=new JButton(".");d5=new JButton("+");d6=new JButton("=");JPanel p=new JPanel(new GridLayout(4,6,10,10));p.add(a1);p.add(a2);p.add(a3);p.add(a4);p.add(a5);p.add(a6);p.add(b1);p.add(b2);p.add(b3);p.add(b4);p.add(b5);p.add(b6);p.add(c1);p.add(c2);p.add(c3);p.add(c4);p.add(c5);p.add(c6);p.add(d1);p.add(d2);p.add(d3);p.add(d4);p.add(d5);p.add(d6);add(p1);add(p,BorderLayout.SOUTH);//将面板p添加到窗口中；并指定面板p位于底部；//为按钮注册监听器；a1.addActionListener(this);a2.addActionListener(this);a3.addActionListener(this);a4.addActionListener(this);a5.addActionListener(this);a6.addActionListener(this);b1.addActionListener(this);b2.addActionListener(this);b3.addActionListener(this);b4.addActionListener(this);b5.addActionListener(this);b6.addActionListener(this);c1.addActionListener(this);c2.addActionListener(this);c3.addActionListener(this);c4.addActionListener(this);c5.addActionListener(this);c6.addActionListener(this);d1.addActionListener(this);d2.addActionListener(this);d3.addActionListener(this);d4.addActionListener(this);d5.addActionListener(this);d6.addActionListener(this);}public void actionPerformed(ActionEvent e){String str=e.getActionCommand();if(str.equals("7")){text.setText( text.getText()+"7");}else if(str.equals("8")){text.setText(text.getText()+"8");}else if(str.equals("9")){text.setText(text.getText()+"9");}else if(str.equals("4")){text.setText(text.getText()+"4");}else if(str.equals("5")){text.setText(text.getText()+"5");}else if(str.equals("6")){text.setText(text.getText()+"6");}else if(str.equals("1")){text.setText(text.getText()+"1");}else if(str.equals("2")){text.setText(text.getText()+"2");}else if(str.equals("3")){text.setText(text.getText()+"3");}else if(str.equals("0")){text.setText(text.getText()+"0");}else if(str.equals(".")){text.setText(text.getText()+"."); }else if(str.equals("+/-")){count++;if(count%2==0){text.setText("+"+text.getText());}elsetext.setText("-"+text.getText());}else if(str.equals("Backspace")){text.setText("");}else if(str.equals("+")){s1=text.getText();s="+";text.setText("");}else if(str.equals("-")){s1=text.getText();s="-";text.setText("");}else if(str.equals("*")){s1=text.getText();s="*";text.setText("");}else if(str.equals("/")){s1=text.getText();s="/";text.setText("");}else if(str.equals("1/x")){s1=text.getText();s="1/x";text.setText("");double num11=Double.parseDouble(s1);double ans=0;ans=1/num11;text.setText(ans+"");}else if(str.equals("sqrt")){s1=text.getText();s="sqrt";text.setText("");double num11=Double.parseDouble(s1);double ans=0;ans=Math.sqrt(num11);text.setText(ans+"");}else if(str.equals("=")){s2=text.getText();double num11=Double.parseDouble(s1);double num22=Double.parseDouble(s2);double ans=0;if(s.equals("+")){ans=num11+num22;}else if(s.equals("-")){ans=num11-num22;}else if(s.equals("*")){ans=num11*num22;}else if(s.equals("/")){ans=num11/num22;}text.setText(ans+"");}}public static void main(String[] args) {ring ring=new ring();ring.setBounds(400,300,450,300);ring.show();ring.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);}}。