核心代码:
public class BrowseDAL {
public static LinkedHashMap<String, Book> getBookLinkedHashMap(int showNumber) {
String sql = "SELECT * FROM books LIMIT ?, ?";
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
LinkedHashMap<String, Book> bookLinkedHashMap = new LinkedHashMap<>();
try {
connection = JdbcUtils.getConnection();
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setInt(1, showNumber);
preparedStatement.setInt(2, 10);
resultSet = preparedStatement.executeQuery();
while (resultSet.next()) {
Book book = new Book(
resultSet.getInt("id"),
resultSet.getString("name"),
resultSet.getString("author"),
resultSet.getString("pubTime"),
resultSet.getInt("inventory"),
resultSet.getDouble("price"));
bookLinkedHashMap.put(book.name, book);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
JdbcUtils.close(resultSet, preparedStatement, connection);
}
如果客户未进行登录又想要体验其他的功能时,就会在页面下方提示其未登
录,会请求用户在登录后进一步使用,未登录提示图如图 4.2 所示。
图 4.2 未登录提示图