delreader .java

基于目前许多中小型公司, 机关,中小学校,大学院系等都有自己的图书库, 供内部人员借阅。传统的手工登记办法

import java.applet.*;
import javax.swing.*;
import java.awt.*;
import java.sql.*;
import java.awt.event.*;
class Delreader extends JFrame implements ActionListener{
private JTextField textId,textName,textType,textMax;
private JButton ok;
public Delreader(){
	   super("删除读者信息");
	   Container c=getContentPane();
	   JPanel panel=new JPanel();
	   //创建读者编号标签与文本框
	   JLabel labelId=new JLabel("读者编号：");
	   textId=new JTextField(15);
	   panel.add(labelId);
	   panel.add(textId);
	   ok=new JButton("删除"); //创建确定按钮	 
	   ok.addActionListener(this);      //为确定按钮注册监听器                    
	   panel.add(ok);   
	   c.add(panel);
	   setBounds(400,110,300,150);
	   setVisible(true);
	   }
	   public void actionPerformed(ActionEvent e1){
	     if(e1.getSource()==ok){	     	
	     		delete();     	
	     }
	   }
	   void  delete(){
	   		Connection con;
        PreparedStatement sql,sql1;
        ResultSet rs;
        boolean boo=false;
      try {  Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");  
          }
     catch(ClassNotFoundException f){}
      try {  con=DriverManager.getConnection("jdbc:odbc:tushuguan");
             
              sql1=con.prepareStatement("SELECT * FROM reader where rid=?");
             String bianhao;
             bianhao=textId.getText();
             if(bianhao.equals(""))
             	JOptionPane.showMessageDialog(this,"编号不能为空！","提示对话框",JOptionPane.WARNING_MESSAGE);	
             else{
             sql1.setString(1,bianhao); 
             rs=sql1.executeQuery(); 
             if(rs.next())
             boo=true;
             con.close();
             if(boo) 
             {  con=DriverManager.getConnection("jdbc:odbc:tushuguan");
             	sql=con.prepareStatement("delete from reader where rid=?");
             	sql.setString(1,bianhao);
             sql.executeUpdate(); 
             	JOptionPane.showMessageDialog(this,"删除读者成功！","提示对话框",JOptionPane.WARNING_MESSAGE);
             	 } 
            else  JOptionPane.showMessageDialog(this,"删除的读者不存在！","提示对话框",JOptionPane.WARNING_MESSAGE);	 	   
    	con.close();
         }    
       }
      catch(SQLException e2) 
           {  System.out.println(e2);
           }
    }   

    public static void main(String args[]){
	   Delreader frame=new Delreader();
	   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	   
   }
}