dialog.java

图书馆里系统

import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import javax.swing.*;

class Dialog extends Frame implements ActionListener,ItemListener 
{
	Label label1 = new Label("用户名");
	Label label2=new Label("密码");
	Label label3=new Label("登陆类型");
  	TextField textField1 = new TextField();
  	TextField textField2=new TextField();
  	Choice choice1=new Choice();
  	Button button1 = new Button("确定");
  	Button button2 = new Button("取消");
	int n;
  	Connection conn;
  	Statement stmt;
  	ResultSet rs;  
    	String strurl;
  	Dialog() throws Exception
	{
  	super("登陆窗口");
  	setSize(400,300);
		setBackground(new Color(110,200,150));
				this.setLocation(200,200);
  	choice1.add("普通用户");
  	choice1.add("超级用户");
  	setLayout(null);

	
    	label1.setBounds(91, 74, 66, 21);
    	label2.setBounds(91, 120, 63, 22);
    	label3.setBounds(91,160,63,22);
    	textField1.setBounds(165, 74, 114, 21);
    	textField2.setBounds(165, 118, 114, 24);
    	textField2.setEchoChar('*');
   	 choice1.setBounds(165, 160, 114, 24);
    	choice1.addItemListener(this);
        button2.addActionListener(this);
    	button1.setBounds(87, 197, 79, 27);
    	button2.setBounds(200, 198, 85, 26);
    	button1.addActionListener(this);
    	add(label1);
   	add(label2);
   	add(label3);
    	add(textField2);
    	add(textField1);
    	add(choice1);
    	add(button1);
    	add(button2);


    	strurl ="jdbc:odbc:tianxia";

    	Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
    	conn = DriverManager.getConnection(strurl,"sa","");
    	stmt = conn.createStatement();
	
		setVisible(true);
		addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				dispose();
				System.exit(0);
			}
		}); 
	}


	public void actionPerformed(ActionEvent e)
	{
                 
		String str=e.getActionCommand();
		String sql;
		String user,pass;
		if (str.equals("确定"))
		{
			user=textField1.getText().trim();
			pass=textField2.getText().trim();
			
			if (n==0)
			{
			try
			{
        		 rs = stmt.executeQuery("select * from GLYB where 用户名 ='" + user + "' AND 密码='" + pass + "'");
 
				if (rs.next())
				{
					SXLMS frame=new SXLMS();
					setVisible(false);
				}
				else
				{
					JOptionPane.showMessageDialog(null, "用户不存在!");
					textField1.setText("");
					textField2.setText("");	
				}
			}
			 catch (Exception eg) {
        		eg.printStackTrace();
      			}			
			}
			else
			{
			try{
        		 rs = stmt.executeQuery("select * from CJGLYB where 用户名='" + user + "' AND 密码='" + pass + "'");

				if (rs.next())
				{
					LMS frame=new LMS();
					setVisible(false);
				}
				else
				{
					JOptionPane.showMessageDialog(null, "用户不存在!");
					textField1.setText("");
					textField2.setText("");	
				}
			}
			 catch (Exception eg) {
        		eg.printStackTrace();
      			}
			
			}
	
	
		}
                if(str.equals("取消"))
                {
                   System.exit(0);
                 }

	}

	public void itemStateChanged(ItemEvent e)
	{
		if(choice1.getSelectedIndex()==1)
		{
			n=1;
		}
		else
		{
			n=0;
		}
			
	}
}