my JDBC （oracle）

                Connection  con = null;
		PreparedStatement statement = null;
		ResultSet set = null;
		try {
			Class.forName("oracle.jdbc.OracleDriver");
			con = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:ORCL","System","a5121921");
			String sql = "select * from Custom where C_Id =?";
			statement = con.prepareStatement(sql);
			statement.setInt(1, 1);
			set = statement.executeQuery();
		
		}catch(Exception e){
			e.printStackTrace();
		}finally {
				try {
					con.close();
					statement.close();
				} catch (SQLException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				}