oplogin.java

老师要求我们用java 做的学生信息管理系统

package collegems;
import java.awt.event.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import java.sql.*;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
import dbcon.*;



public class OpLogin extends JDialog {

	private JPasswordField passwordField;
	private JTextField textField;
	private JButton button;
	private JButton button_1;
	JFrame jframe;
	/**
	 * Launch the application
	 * @param args
	 */
	public static void main(String args[]) {
		try {
			final OpLogin dialog = new OpLogin();
			dialog.addWindowListener(new WindowAdapter() {
				public void windowClosing(WindowEvent e) {
					System.exit(0);
				}
			});
			dialog.button_1.addActionListener(new ActionListener() {
				public void actionPerformed(ActionEvent e) {
					dialog.dispose();							
				}
			});
			dialog.button.addActionListener(new ActionListener() {
				public void actionPerformed(ActionEvent e) {
					ResultSet rs=null;
					try{
						DbCon db=new DbCon();
						String sql="select * from user where username='"+dialog.textField.getText()+"' and password='"+(new String(dialog.passwordField.getPassword()))+"'";
						rs=db.QueryDb(sql);
						if(rs.next())
							{
							JOptionPane.showMessageDialog(null, "登录系统成功！");
							dialog.dispose();
							MainFrame window = new MainFrame();
							window.frame.setVisible(true);
								db.con.close();	
								System.out.println("连接关闭！");
								}
						else
							{JOptionPane.showMessageDialog(null, "输入的用户或口令错误，请重新输入！");
							dialog.textField.setText(null);
							dialog.passwordField.setText(null);
							 
							}
						
					}catch(SQLException e1){
						e1.printStackTrace();
					}
					//dialog.dispose();							
				}
			});
			dialog.setVisible(true);
	
	}catch(Exception e2){
		e2.printStackTrace();
	}
}

	/**
	 * Create the dialog
	 */
	public OpLogin() {
		super();
		getContentPane().setLayout(null);
		setTitle("用户登录");
		setBounds(100, 100, 285, 213);

		final JPanel panel = new JPanel();
		panel.setLayout(null);
		panel.setBounds(17, 21, 250, 149);
		getContentPane().add(panel);

		final JLabel label = new JLabel();
		label.setBounds(10, 21, 58, 18);
		label.setText("用户名：");
		panel.add(label);

		textField = new JTextField();
		textField.setBounds(74, 19, 138, 22);
		panel.add(textField);

		final JLabel label_1 = new JLabel();
		label_1.setText("口    令：");
		label_1.setBounds(10, 59, 58, 18);
		panel.add(label_1);

		passwordField = new JPasswordField();
		passwordField.setBounds(74, 57, 138, 22);
		panel.add(passwordField);

		button = new JButton();
		button.setText("登录");
		button.setBounds(10, 105, 106, 28);
		panel.add(button);

		button_1 = new JButton();
		button_1.addActionListener(new ActionListener() {
			public void actionPerformed(final ActionEvent e) {
			}
		});
		button_1.setText("退出");
		button_1.setBounds(139, 105, 106, 28);
		panel.add(button_1);
		//
	}

}