mainclass.java

一个用java语言编写的基于数据库的系统

import javax.swing.JOptionPane;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
public class MainClass extends JFrame{
	private JButton jbLogin=new JButton("普通用户登录(A)");
	private JButton jbAdmin=new JButton("管 理 员登录(D)");
	private JButton jbCancel=new JButton("  取  消(C)  ");
	private JLabel jlUser;
	private JLabel jlPass;
	private JLabel jt1=new JLabel("欢迎进入郑州市公交车管理系统!希望此软件能为您的出行带来方便!",JLabel.CENTER);
	private JLabel jt2=new JLabel("普通用户直接点击‘普通用户登录’，管理员可以点击‘管理员登录’进入。",JLabel.CENTER);
	public JTextField jtUser=new JTextField(14);
	public JPasswordField jtPass=new JPasswordField(14);
	private JPanel jp1=new JPanel();
	private JPanel jp2=new JPanel();
	private JPanel jp=new JPanel();
	private JPanel jp3=new JPanel();
	private JPanel jp4=new JPanel();
	private DataBase database;
	private  MainMenu mainmenu=new MainMenu();
	private JFrame jf=new JFrame();
	private static int num =0;
	public MainClass(){
		database =new DataBase();
        jt1.setFont(new Font("楷体", 0, 12));
        jt2.setFont(new Font("楷体", 0, 12));
        jbLogin.setFont(new Font("楷体", 0, 12));
        jbAdmin.setFont(new Font("楷体", 0, 12));
        jbCancel.setFont(new Font("楷体", 0, 12));
        jp4.setLayout(new GridLayout(2,1,2,2));
        jp4.add(jt1);
        jp4.add(jt2);
		ImageIcon iconUser = new ImageIcon("image/user20.gif");
	    ImageIcon iconPass = new ImageIcon("image/key20.gif");
	    jlUser = new JLabel("用户名", iconUser, SwingConstants.LEFT);
		jlPass = new JLabel("密  码", iconPass, SwingConstants.CENTER);
		jlUser.setFont(new Font("楷体", 0, 12));
        jlPass.setFont(new Font("楷体", 0, 12));
		jbLogin.setToolTipText("普通用户登录");
		jbAdmin.setToolTipText("管理员登录");
		jbCancel.setToolTipText("取消操作");
		jp2.setLayout(new GridLayout(2,1,5,5));
		jp2.add(jlUser);
		jp2.add(jlPass);
		jp1.setLayout(new GridLayout(2,1,2,2));
		jp1.add(jtUser);
		jp1.add(jtPass);
         jf.add(mainmenu,BorderLayout.CENTER);
         jf.setTitle("公交车管理主界面");
         jf.pack();
		jp.setLayout(new FlowLayout());
		jp.add(jbLogin);
		jp.add(jbAdmin);
		jp.add(jbCancel);
		jbLogin.setMnemonic(KeyEvent.VK_A);
		jbAdmin.setMnemonic(KeyEvent.VK_D);
		jbCancel.setMnemonic(KeyEvent.VK_C);
		jbCancel.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				System.exit(0);
			}
		});
		jbLogin.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				setVisible(false);//关闭当前窗体
				jf.setVisible(true);
			}
			});
		jbAdmin.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				String User=jtUser.getText().trim();
				String Pass=jtPass.getText().trim();
				boolean a=database.isLogin(User,Pass);
				if(a == false){
				JOptionPane.showMessageDialog(null,"输入的用户名或密码错误!","提示",3);
				jtUser.setText("");
				jtPass.setText("");
				num++;
				jf.setVisible(false);
				if(num==3){
				JOptionPane.showMessageDialog(null,"您无权进入本系统!","警告",1);
				System.exit(0);
			   }
               }
               else if(a==true){
			    setVisible(false);
			    jf.setVisible(true);
			      }
				}
			});
		jp3.add(jp2,BorderLayout.WEST);
		jp3.add(jp1,BorderLayout.CENTER);
		jp3.add(jp4,BorderLayout.EAST);
		add(jp3,BorderLayout.CENTER);
		add(jp,BorderLayout.SOUTH);
	}
}