logframe.java

书籍管理系统

/**********************************
 * FileName:LogFrame.java
 * Function:显示登录窗口界面
 * Time:2005 1.7
 **********************************/

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

class LogFrame extends Frame implements ActionListener ,TextListener
{
	Label userName = new Label ("口令");
	Label password = new Label ("密码");                                                                
	Label lbName  =new Label ("                                                ");
    Label lbLog    = new Label ("               ");	
	TextField tfName = new TextField (15);
	TextField tfPW   = new TextField(15);
    Button btnConfirm = new Button ("确        定");
    Button btnCancel  = new Button ("取        消");
    Button btnAbout  = new Button("简        介");
	Dialog MegDlg;
	Button btnY;
	private int login = 0; 
	private Connection loginconnection;
    private Statement loginstatement; 	
    private ResultSet loginresultSet;
	
	LogFrame()
	{
		super("登录窗口");
		GridBagLayout gbLayout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints ();
		setLayout(gbLayout);
		Color MyColor = new Color (0,200,255);
		this.setBackground (MyColor);
		
		gbc.gridx=2;gbc.gridy =2;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE;
		gbc.anchor =GridBagConstraints.CENTER ;
		gbc.weightx  = 1;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (userName,gbc);
		add(userName);
			
			
		gbc.gridx=3;gbc.gridy =2;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE   ;
		gbc.anchor =GridBagConstraints.WEST ;
		gbc.weightx  = 0;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (tfName,gbc);
		tfName.addTextListener (this);
		add(tfName);
		
		gbc.gridx=3;gbc.gridy =3;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE;
		gbc.anchor =GridBagConstraints.WEST   ;
		gbc.weightx  = 1;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (lbName,gbc);
		add(lbName);
		
		gbc.gridx=2;gbc.gridy =5;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE;
		gbc.anchor =GridBagConstraints.CENTER  ;
		gbc.weightx  = 1;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (password,gbc);
		add(password);	
		
		gbc.gridx=3;gbc.gridy =5;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE  ;
		gbc.anchor =GridBagConstraints.WEST ;
		gbc.weightx  =0;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (tfPW,gbc);
		add(tfPW);
		tfPW.addTextListener(this);
			
		gbc.gridx=3;gbc.gridy =6;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE;
		gbc.anchor =GridBagConstraints.WEST  ;
		gbc.weightx  = 1;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (lbLog,gbc);
		add(lbLog);
			
		gbc.gridx=2;gbc.gridy =7;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE   ;
		gbc.anchor =GridBagConstraints.EAST;
		gbc.weightx  = 1;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (btnConfirm,gbc);
		btnConfirm.addActionListener(this);
		add(btnConfirm);
	          
		gbc.gridx=3;gbc.gridy =7;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE  ;
		gbc.anchor =GridBagConstraints.WEST   ;
		gbc.weightx  =1;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (btnCancel,gbc);
		btnCancel.addActionListener (this);
		add(btnCancel);
			
		gbc.gridx=3;gbc.gridy =7;
		gbc.gridwidth =1;gbc.gridheight =1;
		gbc.fill=GridBagConstraints.NONE      ;
		gbc.anchor =GridBagConstraints.CENTER;
		gbc.weightx  = 1;  gbc.weighty = 0;
		gbc.insets = new Insets (2,5,1,5);
		gbLayout.setConstraints (btnAbout,gbc);
		btnAbout.addActionListener (this);
		add(btnAbout);		
		btnY= new Button("返回");
		btnY.addActionListener (this);
			
		 
		setSize(340,350);
		setResizable(false); 
		setLocation (350,250);
		setVisible (true);
		addWindowListener(new WindowAdapter() 
      	{
        	public void windowClosing(WindowEvent e) 
        	{
            	System.exit(0);
        	}
      	});

	}
	
	public void actionPerformed(ActionEvent e)
	{
		if(e.getActionCommand () == "确        定")
		{
			logindispose();
			if(login == 1)
            {
				Frame f = new MainFrame();
               	f.show();
               	dispose();
            }

		}
		else if(e.getActionCommand () =="取        消")
			dispose();
		else if(e.getActionCommand () == "简        介")
		{
			MegDlg =new Dialog (this,"简介",true);
			GridBagConstraints constraints = new GridBagConstraints ();
			Panel txtPanel =new Panel ();
			TextArea txtAbout =new TextArea ();
			Font txtFont = new Font("TimesRoman",Font.BOLD ,14);
			txtAbout.setFont (txtFont);
			txtAbout.setEditable (false);
			txtAbout.setText("     图书管理系统1.0版\n\n"+
							 "设计者:孔帅、施义森\n"+
							 "       倪磊、张春垒\n"+
							 "联系方式:0731-2618605\n"+
							 "地址:长沙理工大学");
			txtPanel.setLayout(new BorderLayout ());
			txtPanel.add(txtAbout,BorderLayout.CENTER );
			
			Panel butPanel = new Panel ();
			butPanel.setLayout (new GridBagLayout ());
			constraints.weightx =20;
			constraints.weighty =20;
			constraints.gridx =0;
			constraints.gridy =0;
			constraints.gridwidth =2;
			constraints.gridheight =3;
			butPanel.add(btnY,constraints);
			
			MegDlg.add(txtPanel,BorderLayout.CENTER );
			MegDlg.add(butPanel,BorderLayout.SOUTH );
			
			MegDlg.setSize (200,200);
			MegDlg.setLocation (690,300);
			MegDlg.setVisible (true);
		}
		else if(e.getActionCommand () =="返回")
			MegDlg.dispose();
	}
	
	public void textValueChanged(TextEvent e)
	{
		if(e.getSource () ==tfPW)
			tfPW.setEchoChar ('*');
		if(e.getSource () == tfName)
			lbName.setText (tfName.getText ());
	}
	
	private void logindispose()
	{
		String url = "jdbc:odbc:book_db"; 
    	String username = "sa"; 
    	String password = "2259853"; 
    	//加载驱动程序以连接数据库
      	try 
      	{ 
        	Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ); 
        	loginconnection = DriverManager.getConnection( url,username,password ); 
      	} 
      	//捕获加载驱动程序异常
      	catch ( ClassNotFoundException cnfex ) 
      	{ 
        	System.err.println("装载 JDBC/ODBC 驱动程序失败。" ); 
        	cnfex.printStackTrace(); 
         	System.exit( 1 );  // terminate program 
      	} 
      	//捕获连接数据库异常
      	catch ( SQLException sqlex ) 
      	{ 
         	System.err.println( "无法连接数据库" ); 
         	sqlex.printStackTrace(); 
         	System.exit( 1 );  // terminate program 
      	} 
     	
     	try
     	{
     		String loginquery;
     		String loginusename = tfName.getText();
         	String loginpassword = tfPW.getText();
         	
         	loginquery = "select * from entry where (passname='"+loginusename +
   							  "' and	password = '"+loginpassword+"')";
   							  
   			loginstatement = loginconnection.createStatement(); 
        	loginresultSet = loginstatement.executeQuery( loginquery ); 
        	boolean Records = loginresultSet.next();
        	if ( ! Records ) 
      		{ 
        		lbLog.setText ("登录失败") ;
        		return; 
      		} 
      		else
      		{
      			login = 1 ;	
      		}
      		loginconnection.close();
        }
     	catch(SQLException sqlex)
     	{
     		sqlex.printStackTrace();
     	}	
     }

	
}