package com.example; import javax.swing.*; import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Random; public class Main extends JFrame implements ActionListener { JButton jb1,jb2; JTextField tf1,tf3; JPasswordField tf2; JLabel jl1,jl2,jl3,jl4,jl5; Random rand = new Random(); Main(){ super("登录"); jb1=new JButton("登录"); jb2=new JButton("取消"); tf1=new JTextField(6); tf2=new JPasswordField(6); tf3=new JTextField(6); jl1=new JLabel("用户名",JLabel.CENTER); jl2=new JLabel("密码",JLabel.CENTER); jl3=new JLabel("验证码",JLabel.CENTER); jl4=new JLabel("验证码:",JLabel.CENTER); jl5=new JLabel("",JLabel.CENTER); jb1.addActionListener(this); jb2.addActionListener(this); setLayout(new GridLayout(5,2)); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); add(jl1);add(tf1); add(jl2);add(tf2); add(jl3);add(tf3); add(jl4);add(jl5); add(jb1);add(jb2); jl5.setText(Integer.toString(rand.nextInt(100)+100)); setBounds(500,100,500,500); setVisible(true); } @Override public void actionPerformed(ActionEvent e) { if(e.getSource()==jb1){ Jdbc jdbc = new Jdbc(); String sql = "select * from user where username='"+tf1.getText()+"' and password='"+tf2.getText()+"'"; ; try { ResultSet rs = jdbc.query(sql); jdbc.close(); if(rs.next()&&tf3.getText().equals(jl5.getText())) { JOptionPane.showMessageDialog(null, "登录成功"); new Home(); this.setVisible(false); } else{ JOptionPane.showMessageDialog(null,"登录失败"); jl5.setText(Integer.toString(rand.nextInt(100)+100)); } } catch (SQLException ex) { throw new RuntimeException(ex); } }else if(e.getSource()==jb2){ System.exit(0); } } public static void main(String[] args) { new Main(); } }