how we can give jdbc connection?

package apptest;

import java.sql.*;

public class AppTest {
// Code s7 Worked 

    public static void main(String[] args) {
        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
            String connectionUrl = "jdbc:sqlserver://localhost:1433;"
                    + "databaseName=Northwind;user=sa;password=;";
            Connection con = DriverManager.getConnection(connectionUrl);
            Statement stmt = null;
            ResultSet rs = null;
            // SQL query command
             String SQL = "SELECT * FROM Products";
            stmt = con.createStatement();
            System.out.println("Connection is created...");

            rs = stmt.executeQuery(SQL);
            while (rs.next()) {

                System.out.println(rs.getString("ProductName") + " : " + rs.getString("UnitPrice"));
               
                System.out.println(" done");

            }

            con.close();
            System.out.println("Connection is closed...");

        } catch (SQLException e) {
            System.out.println("SQL Exception: " + e.toString());
        } catch (ClassNotFoundException cE) {
            System.out.println("Class Not Found Exception: " + cE.toString());
        }
    }
}