import java.awt.*; import java.awt.event.*;import javax.swing.*;import java.math.*;public class zuoye10_3{ public static void main(String args[]){ MathWindow win=new MathWindow(); }}class MathWindow extends JFrame implements ActionListener{ JButton button1,button2,button3,button4; JTextField text1,text2,text3; MathWindow(){ text1=new JTextField(10); text2=new JTextField(10); text3=new JTextField(10); button1=new JButton("加"); button2=new JButton("减"); button3=new JButton("乘"); button4=new JButton("除"); setLayout(new FlowLayout()); add(text1); add(text2); add(text3); add(button1); add(button2); add(button3); add(button4); button1.addActionListener(this); button2.addActionListener(this); button3.addActionListener(this); button4.addActionListener(this); setBounds(200,200,260,190); setVisible(true); validate(); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); }public void actionPerformed(ActionEvent e){ if(e.getSource()==button1){ String s1=text1.getText(); String s2=text2.getText(); BigInteger n; BigInteger n1=new BigInteger(s1); BigInteger n2=new BigInteger(s2); n=n1.add(n2); text3.setText(n.toString());}else if(e.getSource()==button2){ String s1=text1.getText(); String s2=text2.getText(); BigInteger n; BigInteger n1=new BigInteger(s1); BigInteger n2=new BigInteger(s2); n=n1.subtract(n2); text3.setText(n.toString());}else if(e.getSource()==button3){ String s1=text1.getText(); String s2=text2.getText(); BigInteger n; BigInteger n1=new BigInteger(s1); BigInteger n2=new BigInteger(s2); n=n1.multiply(n2); text3.setText(n.toString());}else if(e.getSource()==button4){ String s1=text1.getText(); String s2=text2.getText(); BigInteger n; BigInteger n1=new BigInteger(s1); BigInteger n2=new BigInteger(s2); n=n1.divide(n2); text3.setText(n.toString());} }}