www.pudn.com > st.rar > LoginDia.java

import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*; 
import java.util.*; 
import java.sql.*; 
 
 
public class LoginDia extends JDialog implements ActionListener 
{ 
      JPanel p1=new JPanel(); 
      JPanel p2=new JPanel(); 
      JPanel p3=new JPanel(); 
      JPanel p4=new JPanel(); 
      JPanel p5=new JPanel(); 
    JTextField UserNameText=new JTextField(15); 
    JPasswordField PassWordText=new JPasswordField(15); 
    JButton ok=new JButton("学生登录");  
    JButton cancel=new JButton("取消"); 
    JButton register=new JButton("注册"); 
    JButton teacherLogin=new JButton("老师登录"); 
    ///////////////////////// 
    String sql;  
    Connection conn;  
    Statement stmt;  
    ResultSet rs;  
    ////// 
    String ID=new String(); 
  
    public LoginDia() 
    { 
        setModal(true); 
        
         
        Container contentPane=this.getContentPane(); 
        contentPane.setLayout(new GridLayout(5,1)); 
    
        p2.add(new JLabel("用户名："));p2.add(UserNameText); 
        p3.add(new JLabel("密   码："));p3.add(PassWordText); 
        p4.add(teacherLogin);p4.add(ok);p4.add(register);p4.add(cancel); 
       //////////////////// 
        ok.addActionListener(this);       
        cancel.addActionListener(this); 
        register.addActionListener(this); 
        UserNameText.addActionListener(this); 
        PassWordText.addActionListener(this); 
        teacherLogin.addActionListener(this); 
        
        contentPane.add(p1); 
        contentPane.add(p2); 
        contentPane.add(p3); 
        contentPane.add(p4); 
        contentPane.add(p5); 
        ////////////////////////// 
        Color c=new Color(241,250,255); 
        p1.setBackground(c); 
        p2.setBackground(c); 
        p3.setBackground(c); 
        p4.setBackground(c); 
        p5.setBackground(c); 
         
        ////////////////////////////////////// 
        setDefaultCloseOperation(JDialog.EXIT_ON_CLOSE); 
        setSize(400,300); 
        Dimension screen=Toolkit.getDefaultToolkit().getScreenSize(); 
        setLocation((screen.width-400)/2,(screen.height-300)/2); 
        setTitle("登录窗口"); 
        setResizable(false); 
        setVisible(true);     
    } 
    public void actionPerformed(ActionEvent e){ 
        if(e.getSource()==ok||e.getSource()==PassWordText){ 
            try{ 
               Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");  
               String url="jdbc:odbc:SUMMIT";  
               String user="sa";  
               String password="198662";  
               conn= DriverManager.getConnection(url,user,password); 
               stmt=conn.createStatement();  
               String tem=UserNameText.getText().trim(); 
               ID=tem; 
               sql="select SPASSWD from Student where SNO=";  
               sql=sql+"'"+tem+"'"; 
               
          
               rs=stmt.executeQuery(sql);  
               rs.next(); 
 
        //////登录成功 
            if(rs.getString(1).trim().equals((String)PassWordText.getText().trim())) 
               { 
                   
                   rs.close();  
                   stmt.close(); 
                   conn.close();  
                   dispose(); 
                  
                  StudentFrame studentFrame=new StudentFrame(ID);  
            } 
            else{ 
                   //////////登录失败 
                JOptionPane.showMessageDialog(null,"用户名或密码错误！"); 
                UserNameText.requestFocus(); 
                UserNameText.setSelectionStart(0); 
                UserNameText.setSelectionEnd(UserNameText.getText().length());   } 
        }catch(Exception ee){ JOptionPane.showMessageDialog(null,"用户名不存在或"+" 连接数据库错误"); } 
        } 
        /////////////注册 
        if(e.getSource()==register){ 
            try{ RegisterDia register=new RegisterDia(); 
                  UserNameText.setText(""); 
                 PassWordText.setText(""); 
                 UserNameText.requestFocus();} 
                  catch(Exception eee){JOptionPane.showMessageDialog(null,eee.getMessage()+"  开启注册窗口错误");} 
               } 
         
        if(e.getSource()==cancel){ 
            System.exit(0); 
        }  
        if(e.getSource()==UserNameText){ 
            PassWordText.requestFocus();} 
       if(e.getSource()==teacherLogin){ 
    	   try{ 
               Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");  
               String url="jdbc:odbc:SUMMIT";  
               String user="sa";  
               String password="198662";  
               conn= DriverManager.getConnection(url,user,password); 
               stmt=conn.createStatement();  
               String tem=UserNameText.getText().trim(); 
               sql="select * from Teacher where ID=";  
               sql=sql+"'"+tem+"'"; 
               rs=stmt.executeQuery(sql);  
               rs.next(); 
               if(rs.getString(2).trim().equals(PassWordText.getText().toString().trim())) 
               {   conn.close(); 
                  stmt.close(); 
                  dispose();  
                  new TeacherFrame(); 
                 } 
               else{ 
            	   JOptionPane.showMessageDialog(null, "登录失败"); 
            	   PassWordText.setText(""); 
            	   UserNameText.setText(""); 
            	   UserNameText.requestFocus(); 
               } 
       }catch(Exception e2){JOptionPane.showMessageDialog(null, "登录失败");} 
       } 
    
} 
}