why i still get false heuSet when it is print out as true?

 statement = connection.createStatement();
                statement1 = connection.createStatement();
                statement2 = connection.createStatement();
                statement3 = connection.createStatement();
                String sql2 = "SELECT mt.staffNo as staffNo, pc.idprogramme as program, pc.numOfStu as numOfStu, mt.pc as pc "
                        + "FROM mastertimetable mt INNER JOIN programmecourse pc "
                        + "ON mt.pc=pc.pc WHERE SemesterSession='" + ss + "'";
                resultSet2 = statement.executeQuery(sql2);

                String staffNo = null;
                String sessions = null;
                int numOfStu = 0;

                int day = 0;
                int times = 0;

                while (resultSet2.next()) {
                    staffNo = resultSet2.getString("staffNo");
                    program = resultSet2.getString("program");
                    numOfStu = resultSet2.getInt("numOfStu");
                    String pc = resultSet2.getString("pc");




                    String Class = "SELECT * FROM class "
                            + "WHERE capacity>='" + numOfStu + "' "
                            + "ORDER BY capacity desc";




                    Class1 = statement1.executeQuery(Class);
                    String idClass = null;
                    while (Class1.next()) {
                        idClass = Class1.getString("idClass");
                        list.add(idClass);
                        //out.println(list);
                    }
                    int c = 0;
                    // int x = 1, y = 1;
                    int size = list.size();
                    while (c < size) {//d5-0-10 //
                        int x = 1;
                        while (x < 6) {//ahad
                            int y = 1;
                            while (y < 10) {//09:00

                                String heu = "SELECT mt.staffNo as staffNo, pc.idprogramme as program, mt.idClass as idClass,"
                                        + " mt.day as day, mt.times as times "
                                        + "FROM mastertimetable mt INNER JOIN programmecourse pc ON mt.pc=pc.pc"
                                        + " WHERE (mt.staffNo='" + staffNo + "' OR pc.idprogramme='" + program + "') AND (mt.idClass='" + list.get(c) + "' "
                                        + "OR mt.day=" + x + " OR mt.times=" + y + ") AND mt.SemesterSession='" + ss + "'";

                                heuSet = statement2.executeQuery(heu);

                                out.println(heuSet.next());
                                out.println("<br>");

                                if (heuSet.next() == false) {
                                    s = list.get(c).toString();
                                    day = x;
                                    times = y;
                                    out.println(heu);
                                    break;
                                } else {
                                    y++;
                                }



                            }
                            x++;
                            break;

                        }

                        c++;
                        break;

                    }

                    out.println("<br>");
                    out.println(staffNo);
                    out.println("<br>");
                    out.println(program);
                    out.println("<br>");
                    out.println(numOfStu);
                    out.println("<br>");
                    out.println(idClass);
                    out.println("<br>");
                    out.println("x = " + day);
                    out.println("y = " + times);
                    out.println("<br>");
                    String sql = "UPDATE mastertimetable SET idClass='" + idClass + "', day='" + day + "', times='" + times + "'"
                            + "  WHERE (staffNo='" + staffNo + "' AND pc='" + pc + "') AND SemesterSession='" + ss + "'";
                    int q = statement3.executeUpdate(sql);

                }