public void addBorrower()
    {
        String borrowerEntry = borrowerField.getText();
        try 
        {
        int borrowerEntryInted = Integer.valueOf(borrowerEntry).intValue();
        }
        catch (NumberFormatException e)
        {
            JOptionPane.showMessageDialog(errorPane, "Please enter a whole number into the borrower field");
            return;
        }
        if (lastBookCount == 0)
        {
            JOptionPane.showMessageDialog(errorPane, "The last search generated no books");
        }
        else if (lastBookCount > 1)
        {
            JOptionPane.showMessageDialog(errorPane, "The last search generated more than one book");
        }
        else if (borrowerEntry.length() == 0)
        {
            JOptionPane.showMessageDialog(errorPane, "The borrower text field is empty, please add a borrower id");
        }
    }