package pkgfinal;
import java.sql.*;
import java.util.LinkedList;
import java.util.logging.Level;
import java.util.logging.Logger;

public class ConexionMySQL {
    Connection co;
    Statement stm;

    public ConexionMySQL(){

        try{
            Class.forName("com.mysql.jdbc.Driver");
            String url="jdbc:mysql://localhost/estaciones?user=admin&password=123";
            Connection co = DriverManager.getConnection(url);
            Statement stm1 = co.createStatement();
            Statement stm2 = co.createStatement();
            Statement stm3 = co.createStatement();

            ResultSet l1 = stm1.executeQuery("select * from linea1");
            ResultSet l2 = stm2.executeQuery("select * from linea2");
            ResultSet l3 = stm3.executeQuery("select * from linea3");

            LinkedList ln1 = new LinkedList();
            LinkedList ln2 = new LinkedList();
            LinkedList ln3 = new LinkedList();

            while(l1.next())
                ln1.addLast(l1.getString(3));
            while(l2.next())
                ln2.addLast(l2.getString(3));
            while(l3.next())
                ln3.addLast(l3.getString(3));

            System.out.println("linea1: "+ln1);
            System.out.println("linea2: "+ln2);
            System.out.println("linea3: "+ln3);
        }
        catch(ClassNotFoundException exc){
            exc.printStackTrace();
        }
        catch (SQLException ex) {
            Logger.getLogger(ConexionMySQL.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

ResultSet l1 = stm1.executeQuery("select * from linea1");