public void delete(int bookId){
		String delete = "delete from book where id = "+ bookId+ ";";
		
		DBManager dbm = null;
		Connection conn = null;
		Statement stmt = null;
		try{
			dbm = new DBManager();
			conn = dbm.getConnection();
			stmt = conn.createStatement();
			stmt.executeUpdate(delete);
		}catch(Exception e){
			e.printStackTrace()
			;
		}finally{
			dbm.closeAll(null, stmt, conn);
		}
	}