loginjframe.java

用java开发的一个进销存,开发工具jc, 数据库sql server

package classfile;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.sql.*;
import java.util.*;
class LoginJFrame extends JFrame{
	private JLabel jluser,jlpass;				
	private JTextField jtuser;		
	private JButton confirm,cancel,login;		
	static String usernamelogin;				
	private JPasswordField jtpass;
	private LoginJFrame(){
		jluser = new JLabel("用户名:");	
		jlpass = new JLabel("密    码:");
		jtuser = new JTextField(15);
		jtpass = new JPasswordField(15);
		confirm = new JButton("确定");
		cancel = new JButton("取消");
		login = new JButton("注册");
		
		Container c = getContentPane();
		c.setLayout(new FlowLayout());
		c.add(jluser);
		c.add(jtuser);
		c.add(jlpass);
		c.add(jtpass);
		c.add(confirm);
		c.add(cancel);
		c.add(login);
		jtuser.addKeyListener(new KeyAdapter(){
			public void keyPressed(KeyEvent eJtuser){
				if(eJtuser.getKeyCode()==10){
					jtpass.requestFocus(true);
				}	
			}
		});
		jtpass.addKeyListener(new KeyAdapter(){
			public void keyPressed(KeyEvent eJtuser){
				if(eJtuser.getKeyCode()==10){
					confirmAction();
				}	
			}
		});
		confirm.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent eConfirm){
				confirmAction();
			}
		});	
		
		cancel.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent eCancel){
				System.exit(1);
			}
		});
		
		login.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent eLogin){
				new Login(); 
			}
		});
		
				
		this.setIconImage(Toolkit.getDefaultToolkit().getImage("image\\sreenicon.gif"));
		setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
		setSize(250,130);
		Commonable.screenCenter(this);		
		setResizable(false);
		setVisible(true);
	}
	
	private void confirmAction(){
		MakeDatebase conn = new MakeDatebase();
		conn.connectionSql();
		try{
			String sql = "select username,password from userinfo where username='"+jtuser.getText()+"' and password='"+jtpass.getText()+"'";
			conn.selectDate(sql);
			if(conn.rct.next()){
				JOptionPane.showMessageDialog(null,"登录成功");
				usernamelogin = jtuser.getText();
				setVisible(false);
				MainJFrame frm = new MainJFrame();
			}
			else
				JOptionPane.showMessageDialog(null,"用户名或密码有误");
		}
		catch(Exception ex4){
			JOptionPane.showMessageDialog(null,"登录时出错,请重新操作!!");
		}
		finally{
			conn.closeConnection();
		}		
	}
	public static void main(String[] args){
    	LoginJFrame frm = new LoginJFrame();
	}
		
}