jsp无法连接到mysql数据库

String url = "jdbc:mysql://localhost:3306/mydatabase";
String user = "username";
String password = "password";

Class.forName("com.mysql.jdbc.Driver");

GRANT ALL PRIVILEGES ON mydatabase.* TO 'username'@'localhost';
FLUSH PRIVILEGES;

<%@ page import="java.sql.*" %>
<%
    String url = "jdbc:mysql://localhost:3306/mydatabase";
    String user = "username";
    String password = "password";
    Connection conn = null;
    Statement stmt = null;
    ResultSet rs = null;
    try {
        Class.forName("com.mysql.jdbc.Driver");
        conn = DriverManager.getConnection(url, user, password);
        stmt = conn.createStatement();
        rs = stmt.executeQuery("SELECT * FROM mytable");
        while (rs.next()) {
            out.println(rs.getString("columnName") + "<br>");
        }
    } catch (Exception e) {
        out.println("Error: " + e.getMessage());
    } finally {
        try { rs.close(); } catch (Exception e) {}
        try { stmt.close(); } catch (Exception e) {}
        try { conn.close(); } catch (Exception e) {}
    }
%>