import java.io.*;
import java.sql.*;

/* IP Adress:       134.58.95.246
 * Port:            1521
 * Username:        student
 * Password:        student
 */

public class Main {

    static {
        try {
            /* Type 4 Driver */
            Class.forName("oracle.jdbc.OracleDriver");
        }
        catch (ClassNotFoundException e) {
            System.err.println("Could not load Oracle 10g driver \n");
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }

    public static String askDiscipline() {

        String discipline = null;
        try
        {
        BufferedReader br1 = new BufferedReader(new InputStreamReader(System.in));
        System.out.print("Enter a discipline: ");
        discipline = br1.readLine();
        }
        catch (IOException e)
        {
        System.out.print("Failed to get discipline");
        System.out.println(":" + e.getMessage());
        System.exit(1);
        }
        return discipline;
    }

    public static void main(String[] args) {

        /* Location of the database */
        String url = "jdbc:oracle:thin:@134.58.95.246:1521:XE";


        /* Connect to Oracle database */
        Connection conn = null;
        try {
            conn = DriverManager.getConnection(url, "student", "student");
            System.out.println("Connection established...");
            System.out.println();
        } catch (SQLException e1) {
            e1.printStackTrace();
        }


        /* Initial input */
        String discipline = askDiscipline();
        /* Start loop that asks for input, query, and displays result */
        while (!discipline.equals("0")) {           // => geeft fout: The local variable discipline may not have been initialized
            try {

                /* Query */
                String query =  "SELECT LASTNAME, FIRSTNAME, RESULT " +
                        "FROM ATHLETE.ATHLETE, ATHLETE.DISCIPLINE, ATHLETE.RESULT " +
                        "WHERE ATHLETE.ANR = RESULT.ANR " +
                        "AND DISCIPLINE.DNR = RESULT.DNR " +
                        "AND DISCIPLINE.DNAME = " + discipline; // + " " +
                        //"ORDER BY RESULT DESC LIMIT 0,3 ";
                /* Create statement */

                System.out.println("De query is:\n" + query);

                Statement stmt = conn.createStatement();
                /* Execute the query */
                ResultSet rs = stmt.executeQuery(query);
                /* Output */
                System.out.println("First name // Last name // Result");
                System.out.println("-------------------------------");
                while (rs.next()) {
                    System.out.print(rs.getString(1));
                    System.out.print((" // "));
                    System.out.print(rs.getString(2));
                    System.out.print((" // "));
                    System.out.println(rs.getString(3));
                }
                rs.close();
                stmt.close();
                conn.close();
            }
            catch (SQLException e) {
                System.out.println("SQL Exception: ");
                System.err.println(e.getMessage());
            }
            discipline = askDiscipline();
        }

        System.out.println("End Of Session");
    }
}