java - 无法从 sqlite 表获取记录，出现 ResultSet Closed 错误

Question

public void actionPerformed(ActionEvent e) {
                try{
                    String searchQuery = "select BookTitle,ISBN,Price,IsAvailable from BookDetails where BookTitle =?";
                    PreparedStatement serPST = connector.prepareStatement(searchQuery);
                    serPST.setString(1,textTitleSearch.getText());
                    ResultSet serResult = serPST.executeQuery();
                    int noofbooks = 0;
                    while(serResult.next()){
                        noofbooks++;
                    }
                    if (noofbooks!=0){
                        textResultTitle.setText(serResult.getString("BookTitle"));
                        textResultISBN.setText(Integer.toString((serResult.getInt("ISBN"))));
                        textResultPrice.setText(Integer.toString((serResult.getInt("Price"))));
                        textAvailability.setText(serResult.getString("IsAvailable"));
                        }
                    else{
                        JOptionPane.showMessageDialog(null,"Adjust the title");
                    }
                    serPST.close();
                    serResult.close();
                    }
                catch(Exception errSearch){
                    JOptionPane.showMessageDialog(null, errSearch);
                    System.out.println(errSearch.getCause());

                    }
            }

Answer 1

在 while 循环中，您将光标移动到最后一行，然后在 while 循环之后，您从没有记录的光标中获取结果？

您的代码应该是:

while(serResult.next()){
   noofbooks++;  
   textResultTitle.setText(serResult.getString("BookTitle"));                       
   textResultISBN.setText(Integer.toString((serResult.getInt("ISBN"))));                           
   textResultPrice.setText(Integer.toString((serResult.getInt("Price"))));
   textAvailability.setText(serResult.getString("IsAvailable"));
}
if (noofbooks == 0){
    JOptionPane.showMessageDialog(null,"Adjust the title");
}