Question

用JAVA编写一个用户登陆界面,用户验证通过数据库实现

Answer 1

这是我以前写的系统登录框的login
package java1;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.Rectangle;
import java.awt.Font;

public class login extends JFrame
{
public login() {
try {
jbInit();
}
catch (Exception ex) {
ex.printStackTrace();
}
}
public static void main(String[] args)
{
login frm=new login();
frm.setBounds(300,200,300,260);
frm.setVisible(true);

}

private void jbInit() throws Exception {
this.getContentPane().setLayout(null);
jLabel1.setForeground(Color.red);
jLabel1.setText("用户名");
jLabel1.setBounds(new Rectangle(25, 72, 68, 29));
jButton2.setBounds(new Rectangle(142, 159, 81, 30));
jButton2.setText("取消");
jButton2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
jButton2_actionPerformed(e);
}
});
jButton1.setBounds(new Rectangle(38, 159, 81, 29));
jButton1.setText("确定");
jButton1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
jButton1_actionPerformed(e);
}
});
jTextField1.setBounds(new Rectangle(109, 79, 136, 23));
jPasswordField1.setBounds(new Rectangle(109, 115, 136, 23));
this.getContentPane().add(jLabel1);
jLabel3.setFont(new java.awt.Font("隶书", Font.PLAIN, 24));
jLabel3.setText("学 生 考 试 系 统");
jLabel3.setBounds(new Rectangle(22, 15, 268, 47));
this.getContentPane().add(jTextField1);
this.getContentPane().add(jLabel2);
this.getContentPane().add(jButton2);
this.getContentPane().add(jButton1);
this.getContentPane().add(jLabel3);
this.getContentPane().add(jPasswordField1);
jLabel2.setForeground(Color.red);
jLabel2.setText("密码");
jLabel2.setBounds(new Rectangle(26, 112, 68, 29));
}

JLabel jLabel1 = new JLabel();
JLabel jLabel2 = new JLabel();
JTextField jTextField1 = new JTextField();
JButton jButton1 = new JButton();
JButton jButton2 = new JButton();
JLabel jLabel3 = new JLabel();
JPasswordField jPasswordField1 = new JPasswordField();
main2 wo=new main2();
int sum;

//判断权限的方法
public void success()
{
try{
ResultSet rs1;
String s1="select * from 管理权限 where name='"+jTextField1.getText()+"' and password='"+jPasswordField1.getText()+"'";
rs1=sqlcx.Rs_jiluji(s1);
rs1.first();
sum=Integer.parseInt((String)(rs1.getString(3)));
System.out.println(sum);
very();
}
catch(Exception c){System.out.println("success error");}
}

//根据权限设置窗口
public void very()
{
if (sum==1)
{JOptionPane.showOptionDialog(this, "您现在是以教师权限登陆", "登陆信息"
, JOptionPane.DEFAULT_OPTION,
JOptionPane.ERROR_MESSAGE,
null, null, null);

}
else
{
JOptionPane.showOptionDialog(this, "你现在是以学生权限登陆", "登陆信息"
, JOptionPane.DEFAULT_OPTION,
JOptionPane.ERROR_MESSAGE,
null, null, null);
wo.jButton2.setVisible(false);
wo.jButton3.setVisible(false);
wo.jButton4.setVisible(false);
wo.jButton5.setVisible(false);
wo.jButton6.setVisible(false);
wo.jButton7.setVisible(false);
wo.jButton8.setVisible(false);
wo.jMenu2.setVisible(false);
wo.jMenu3.setVisible(false);
wo.jMenu4.setVisible(false);
}

}

public void jButton1_actionPerformed(ActionEvent e)
{
//判断用户名是否为空
if (jTextField1.getText().length() == 0) {
JOptionPane.showOptionDialog(this, "用户名不能为空", "错误信息"
, JOptionPane.DEFAULT_OPTION,
JOptionPane.ERROR_MESSAGE,
null, null, null);
}
//判断密码是否为空
else if (jPasswordField1.getText().length()==0)
{
JOptionPane.showOptionDialog(this,"密码不能为空", "错误信息"
, JOptionPane.DEFAULT_OPTION,
JOptionPane.ERROR_MESSAGE,
null, null, null);
}
else
{
try
{
ResultSet rs;//声明记录集
String sql="select * from 管理权限 where name='"+jTextField1.getText()+"'";
rs = sqlcx.Rs_jiluji(sql);
if (rs.next())
{
if(jPasswordField1.getText().equals(rs.getString(2)))
{

success();
wo.setBounds(60,40,700,600);
wo.setVisible(true);
this.dispose();
}
else
{
JOptionPane.showOptionDialog(this,"密码错误", "错误信息"
, JOptionPane.DEFAULT_OPTION,
JOptionPane.ERROR_MESSAGE,
null, null, null);
}
}
else
{
JOptionPane.showOptionDialog(this,"没有所要找的用户名", "错误信息"
, JOptionPane.DEFAULT_OPTION,
JOptionPane.ERROR_MESSAGE,
null, null, null);
}

}
catch(Exception c){
JOptionPane.showOptionDialog(this,"连接数据库失败", "错误信息"
, JOptionPane.DEFAULT_OPTION,
JOptionPane.ERROR_MESSAGE,
null, null, null);
}
}
}
public void jButton2_actionPerformed(ActionEvent e) {
System.exit(0);
}
}