Problem when displaying data from a database in an HTML tag select

This is my HTML code:

<select>
<% 
ConectaDB con=new ConectaDB();
try{
    con.conectar();
    String sql="select unique(n_dep) from ocex_uea order by n_dep asc";
    con.st=con.conexion.createStatement(); 
    con.rt=con.st.executeQuery(sql);
    while (con.rt.next()){
        out.println("<option>"+con.rt.getString(2)+"</option>");}
}catch(Exception e){
    out.print(e.toString());}
%>
</select>
<label for="DEPARTAMENTO"><Strong>SELECCIONE DEPARTAMENTO:</Strong></label>

The one with my connection is this:

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class ConectaDB { 
public Connection conexion;

public  Statement st=null;
public  ResultSet rt=null;

public Connection getConnection() {
    return conexion;
}

public void setConexion(Connection conexion) {
    this.conexion = conexion;
}

public ConectaDB conectar() {
    try {
        Class.forName("oracle.jdbc.OracleDriver");
        String BaseDeDatos = "jdbc:oracle:thin:@localhost:1521:XE";
        conexion = DriverManager.getConnection(BaseDeDatos, "ocexpnp", "root");

        if (conexion != null) {
            System.out.println("Conexion exitosa!");
        } 
        else {
            System.out.println("Conexion fallida!");
        }
    } catch (Exception e) {
        e.printStackTrace();
        }   
return this; 
 }
}

When I run the application the "Select" only shows "undefined" instead of showing me the results of that query. Any help, thanks in advance.