public Book querryUseId(int bookId){
		DBManager manager = null;
		String querry = "select * from book where id = "+ bookId +";";
		Connection conn = null;
		Statement stmt = null;
		ResultSet rs = null;
		Book book = null;
		try{
			book = new Book();
			manager = new DBManager();
			conn = manager.getConnection();
			stmt = conn.createStatement();
			rs = stmt.executeQuery(querry);
			
			while(rs.next()){
				book.setId(rs.getInt(1));
				book.setName(rs.getString(2));
				book.setAuthor(rs.getString(3));
				book.setBookman(rs.getString(4));
				book.setPrice(rs.getFloat(5));
				book.setCategoryId(rs.getInt(6));
				book.setIntroduction(rs.getString(7));
				book.setOnSaleDate(rs.getDate(8));
				book.setOnSaleNum(rs.getInt(9));
				book.setRemainNum(rs.getInt(10));
			
				return book;
			}
			
			return book;
		}catch(Exception e ){
			e.printStackTrace();
		}finally{
			manager.closeAll(rs, stmt, conn);
		}
		return book;
	}