做成这些需要学:
1.swing
2.sql server驱动加载,服务器ip端口设置
3.创建数据库,查询语句
界面展示
test3/login.java
package test3;
import java.awt.Dimension; //封装了一个构件的高度和宽度
import java.awt.FlowLayout;
import java.awt.Font;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JPasswordField;
import javax.swing.JButton;
public class login {
//在类中定义主函数
public static void main(String[] args) {
// TODO Auto-generated method stub
//在主函数中,实例化Login类的对象,调用初始化界面的方法
login login = new login();
login.initUI();
}
//在类中定义初始化界面的方法
public void initUI() {
//在initUI中实例化JFrame类的对象
JFrame frame = new JFrame();
//设置窗体对象的属性值
frame.setTitle("Login");//设置窗体标题
frame.setSize(400, 250);//设置窗体大小,只对顶层容器生效
frame.setDefaultCloseOperation(3);//设置窗体关闭操作,3表示关闭窗体退出程序
frame.setLocationRelativeTo(null);//设置窗体相对于另一组间的居中位置,参数null表示窗体相对于屏幕的中央位置
frame.setResizable(false);//禁止调整窗体大小
frame.setFont(new Font("宋体",Font.PLAIN,14));//设置字体,显示格式正常,大小
//实例化FlowLayout流式布局类的对象,指定对齐方式为居中对齐组件之间的间隔为10个像素
FlowLayout fl = new FlowLayout(FlowLayout.CENTER,10,10);
//实例化流式布局类的对象
frame.setLayout(fl);
//实例化JLabel标签对象,该对象显示“账号”
JLabel labname = new JLabel("账号:");
labname.setFont(new Font("宋体",Font.PLAIN,14));
//将labname标签添加到窗体上
frame.add(labname);
//实例化JTextField标签对象化
JTextField text_name = new JTextField();
Dimension dim1 = new Dimension(300,30);
text_name.setPreferredSize(dim1);//设置除顶级容器组件以外其他组件的大小
//将textName标签添加到窗体上
frame.add(text_name);
//实例化JLabel标签对象,该对象显示“密码”
JLabel labpass = new JLabel("密码:");
labpass.setFont(new Font("宋体",Font.PLAIN,14));
//将labpass添加到窗体上
frame.add(labpass);
//实例化JPasswordField
JPasswordField text_password = new JPasswordField();
//设置大小
text_password.setPreferredSize(dim1);
//添加到窗体
frame.add(text_password);
//实例化JButton组件
JButton button1 = new JButton();
//设置按键的显示内容
Dimension dim2 = new Dimension(100,30);
button1.setText("登录");
button1.setFont(new Font("宋体",Font.PLAIN,14));
//设置按键大小
button1.setSize(dim2);
frame.add(button1);
frame.setVisible(true);//窗体可见,一定要放在所有组件加入窗体后
LoginListener ll = new LoginListener(frame,text_name,text_password);
button1.addActionListener(ll);
}
}
test3/LoginListener.java
package test3;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.awt.Font;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class LoginListener implements ActionListener{
private javax.swing.JTextField text_name;
private javax.swing.JPasswordField text_password;
private javax.swing.JFrame login;
public LoginListener(javax.swing.JFrame login,javax.swing.JTextField text_name,javax.swing.JPasswordField text_password)
{//获取登录界面、账号密码输入框对象
this.login=login;
this.text_name=text_name;
this.text_password=text_password;
}
int i=3;//3次登录机会
public void actionPerformed(ActionEvent e)
{
Dimension dim2 = new Dimension(100,30);
Dimension dim3 = new Dimension(300,30);
//生成新界面
javax.swing.JFrame login2 = new javax.swing.JFrame();
login2.setSize(400,200);
login2.setDefaultCloseOperation(3);
login2.setLocationRelativeTo(null);
login2.setFont(new Font("宋体",Font.PLAIN,14)); //宋体,正常风格,14号字体
//创建组件
javax.swing.JPanel jp1 = new JPanel();
javax.swing.JPanel jp2 = new JPanel();
connect conn = new connect();
conn.getConnection();
String usernumber=text_name.getText();
String userpassword=text_password.getText();
Boolean flag=conn.checkAccount(usernumber, userpassword);
if(flag)/*text_name.getText().equals("vv") && text_password.getText().equals("123456")*/
{
JLabel message = new JLabel("登陆成功!");
message.setFont(new Font("宋体",Font.PLAIN,14)); //宋体,正常风格,14号字体
message.setPreferredSize(dim3);
jp1.add(message);
login2.add(jp1,BorderLayout.CENTER);
JButton close = new JButton("确定");
close.setFont(new Font("宋体",Font.PLAIN,14));
//设置按键大小
close.setSize(dim3);
jp2.add(close);
login2.add(jp2,BorderLayout.SOUTH);
close.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
login2.dispose();
menu menu =new menu();
menu.go();
}
});
login2.setResizable(false);
login2.setVisible(true);
//通过我们获取的登录界面对象,用dispose方法关闭它
login.dispose();
menu m =new menu();
}
else
{
JLabel message = new JLabel("密码错误请重试");
message.setFont(new Font("宋体",Font.PLAIN,14)); //宋体,正常风格,14号字体
message.setPreferredSize(dim3);
//将textName标签添加到窗体上
jp1.add(message);
login2.add(jp1,BorderLayout.CENTER);
JButton close = new JButton("确定");
close.setFont(new Font("宋体",Font.PLAIN,14));
//设置按键大小
close.setSize(dim3);
jp2.add(close);
login2.add(jp2,BorderLayout.SOUTH);
close.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
login2.dispose();
}
});
login2.setResizable(false);
login2.setVisible(true);
//通过我们获取的登录界面对象,用dispose方法关闭它
login.dispose();
}
}
}
test3/connnect.java
package test3;
import java.sql.*;
public class connect
{
static Connection con;
public Connection getConnection()
{
try{
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); //数据库驱动加载
System.out.println("数据库驱动加载成功");
}catch(ClassNotFoundException e){
e.printStackTrace();
}
try{
con=DriverManager.getConnection("jdbc:sqlserver://127.0.0.1:1433;DatabaseName=*********","sa","********");//数据库连接//数据库连接,sa是登录名,后面的是数字是密码,db_jdbc是数据库名字
System.out.println("数据库连接成功");
}catch(SQLException e){
e.printStackTrace();
}
return con;
}
public boolean checkAccount(String usernumber, String userpassword) {
try
{
Statement stmt = con.createStatement();
String sqlstmt = "select userpassword from [dbo].[userinfo] where usernumber=" + "'" + usernumber + "'";
ResultSet resultSet = stmt.executeQuery(sqlstmt);
String passWord = "";
while (resultSet.next()) {
passWord = resultSet.getString("userpassword").trim();
if (passWord == userpassword || passWord.equals(userpassword)) {
return true;
} else return false;
}
} catch (SQLException e) {
e.printStackTrace();
}
return false;
}
}