java - 我想将计数查询的值分配给整数变量

Question

`String query = "select count(book_id) as book_id from library_books_details where book_id = ?";`
PreparedStatement psEnd = collegeCon.prepareStatement(query);

psEnd.setInt(1, bookId);

Answer 1

ResultSet rs = psEnd.executeQuery();
      if (rs.next()) {
        int count= rs.getInt(1);
        System.out.println("Count= " + count);
      } else {
        System.out.println("error: could not get the record counts");
      }