复件 jc.java

一个小型的图书管理系统

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;
import java.io.*;
public class Jc{
	JFrame frame=new JFrame("欢迎使用图书管理系统");
	CardLayout myCard;
	JLabel hylabel,zhlabel,malabel;
	JTextField zhfield;
	JPasswordField mafield;
	JButton yesbutton,nobutton;
	
	public static void main(String args[]){
		Jc dl=new Jc();
		dl.go();
	}
	public void go(){
		hylabel = new JLabel("欢迎使用图书管理系统");
		zhlabel = new JLabel("帐号");
		zhfield = new JTextField(15);
		JPanel panel1=new JPanel();
		panel1.add(zhlabel);
		panel1.add(zhfield);
	    malabel = new JLabel("密码");
		mafield = new JPasswordField(15);
		JPanel panel2=new JPanel();
		panel2.add(malabel);
		panel2.add(mafield);
		yesbutton=new JButton("确定");
	    yesbutton.addActionListener(new ActionListener(){	
	    public void actionPerformed(ActionEvent e){
		   String str1=zhfield.getText();
		   String str2=new String(mafield.getPassword());

           if(checkusers(str1,str2)){
                		   Zhujiemian zjm = new Zhujiemian();
		                    zjm.go();
		                    frame.setVisible(false);
	         }
	         else{
	         			JOptionPane.showMessageDialog(null, "输入有误或账号不存在！");
				    	zhfield.setText("");
				    	mafield.setText("");
	         	}	
              }
          }); 

		
		nobutton=new JButton("取消");
		nobutton.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				System.exit(0);
				}
			});
	  JPanel panel3=new JPanel();
	  panel3.add(yesbutton);
	  panel3.add(nobutton);
	  Container contentPane1= frame.getContentPane();
	  contentPane1.setLayout(new GridLayout(4,0));
	  contentPane1.add(hylabel);
	  contentPane1.add(panel1);
	  contentPane1.add(panel2);
	  contentPane1.add(panel3);	
	  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	  frame.setSize(500,450);
	  frame.setVisible(true);		
	}
		public static boolean checkusers(String username1,String userpassword1){
	      boolean a=false;
		try{
		String driver="sun.jdbc.odbc.JdbcOdbcDriver";
		File f=new File("jcdb.mdb");
			String url="Jdbc:Odbc:Driver={MicroSoft Access Driver (*.mdb)};DBQ="+f.getPath();
			Class.forName(driver);
			Connection con=DriverManager.getConnection(url);
			System.out.println("数据源="+con.getCatalog());
			Statement st=con.createStatement();
			String sql="select * from users";

			ResultSet rs=st.executeQuery(sql);

			while(rs.next()){
				String s1=rs.getString(1);
				String s2=rs.getString(2);
				if(s1.equals(username1)&&s2.equals(userpassword1)){
					a=true;
					break;
				}
           
			}
		}catch(Exception e){
			e.printStackTrace();
		}
         return a;
	}	
}