delbookfrm.java

用Java实现的图书馆的管理系统

import java.util.*;
import java.awt.*;
import java.io.*;
import java.net.*;
import java.sql.*;
import java.awt.event.*;
import javax.swing.*;

class Delbookfrm extends JFrame implements ActionListener {
	JLabel l_bookid;
	JTextField t_bookid;
	JButton b_delbook, b_back;
	JPanel pan1, pan2, pan3;

	Statement s;
	ResultSet rs;
	String h1,h2;
	int choice=0;
	Delbookfrm() {

		l_bookid = new JLabel("输入你要删除的书籍的编号：");
		t_bookid = new JTextField("", 10);
		b_delbook = new JButton("删除");
		b_back = new JButton("返回");
		b_delbook.addActionListener(this);
		b_back.addActionListener(this);
		pan1 = new JPanel();
		pan2 = new JPanel();
		pan3 = new JPanel();
		pan1.add(l_bookid);
		pan2.add(t_bookid);
		pan3.add(b_delbook);
		pan3.add(b_back);
		setLayout(new GridLayout(3, 1));
		add(pan1);
		add(pan2);
		add(pan3);
		setBounds(400, 300, 300, 350);


	}

	public void actionPerformed(ActionEvent ed) {
		String JDriver = "sun.Jdbc.Odbc.JdbcOdbcDriver";
		String conURL = "jdbc:odbc:abc";
		try {
			Class.forName(JDriver);
		} catch (java.lang.ClassNotFoundException e1) {
			System.out.println("forname:" + e1.getMessage());
		}
		try {
			Connection con = DriverManager.getConnection(conURL);
			s = con.createStatement();
		} catch (SQLException e1) {
			System.out.println("SQLException:" + e1.getMessage());
		}
		if (ed.getSource() == b_delbook) {
			try{rs=s.executeQuery("select bookid from books ");
			h2=t_bookid.getText();
			
			while(rs.next()){
			    h1= rs.getString(1);
			    if(h1.equals(h2))
			    {choice=1; break;}
			   }
			    
				
			}catch(SQLException e3){
				}
		   if(choice==1)
	         {try {
				s.executeUpdate("delete from books where bookid=" + "'"
						+ t_bookid.getText() + "'");
				l_bookid.setText("书籍删除成功");
			} catch (SQLException e6) {
			}}
		   else{
			   l_bookid.setText("找不到该书的编号");
		   }
		} 
		else if (ed.getSource() == b_back) {
			dispose();
		}
	}
}