?? bookdelete.java
字號:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;
public class BookDelete extends JFrame implements ActionListener
{
DataBaseManager db=new DataBaseManager();
ResultSet rs;
Container c;
JLabel TipLabel=new JLabel("請輸入要刪除的書名:",JLabel.CENTER);
JTextField BookDeleteTextField=new JTextField(15);
JButton YesBtn,ExitBtn;
JPanel panel1=new JPanel();
public BookDelete()
{
super("刪除書籍信息");
c=getContentPane();
c.setLayout(new BorderLayout());
c.add(TipLabel,BorderLayout.NORTH);
c.add(BookDeleteTextField,BorderLayout.CENTER);
YesBtn=new JButton("確定");
ExitBtn=new JButton("退出");
YesBtn.addActionListener(this);
ExitBtn.addActionListener(this);
panel1.add(YesBtn);
panel1.add(ExitBtn);
c.add(panel1,BorderLayout.SOUTH);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==ExitBtn)
{
this.dispose();
}
else if(e.getSource()==YesBtn)
{
try
{
String strSQL="select borrowed_count from books where bookName='"+
BookDeleteTextField.getText().trim()+"'";
rs=db.getResult(strSQL);
if(!rs.first())
{
JOptionPane.showMessageDialog(null,"書庫里沒有你要刪除的書!");
}
else
{
String strSql="delete books where bookName='"+
BookDeleteTextField.getText().trim()+"'and borrowed_count=0";
rs.first();
int count=rs.getInt(1);
if(!(count==0))
{
JOptionPane.showMessageDialog(null,"此書還有學生沒有還!\n現在還不能從書庫中刪除。。。");
this.dispose();
}
else if(db.updateSql(strSql))
{
JOptionPane.showMessageDialog(null,"刪除成功!");
db.closeConnection();
this.dispose();
}
else
{
JOptionPane.showMessageDialog(null,"刪除失??!");
db.closeConnection();
this.dispose();
}
}
}
catch(SQLException sqle)
{
System.out.println(sqle.toString());
}
catch(Exception ex)
{
System.out.println(ex.toString());
}
}
}
}
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