class CurriculumCourseExporter extends AbstractTxtSolutionExporter<CourseSchedule> {
    private static final String OUTPUT_FILE_SUFFIX = "sol";

    public static void main(String[] args) {<FILL_FUNCTION_BODY>}

    @Override
    public String getOutputFileSuffix() {
        return OUTPUT_FILE_SUFFIX;
    }

    @Override
    public TxtOutputBuilder<CourseSchedule> createTxtOutputBuilder() {
        return new CurriculumCourseOutputBuilder();
    }

    public static class CurriculumCourseOutputBuilder extends TxtOutputBuilder<CourseSchedule> {

        @Override
        public void writeSolution() throws IOException {
            for (Lecture lecture : solution.getLectureList()) {
                bufferedWriter.write(lecture.getCourse().getCode()
                        + " r" + lecture.getRoom().getCode()
                        + " " + lecture.getPeriod().getDay().getDayIndex()
                        + " " + lecture.getPeriod().getTimeslot().getTimeslotIndex() + "\r\n");
            }
        }
    }

}

        SolutionConverter<CourseSchedule> converter = SolutionConverter.createExportConverter(
                CurriculumCourseApp.DATA_DIR_NAME, new CurriculumCourseExporter(), new CurriculumCourseSolutionFileIO());
        converter.convertAll();
    
<methods>public non-sealed void <init>() ,public abstract TxtOutputBuilder<org.optaplanner.examples.curriculumcourse.domain.CourseSchedule> createTxtOutputBuilder() ,public java.lang.String getOutputFileSuffix() ,public void writeSolution(org.optaplanner.examples.curriculumcourse.domain.CourseSchedule, java.io.File) <variables>protected static final java.lang.String DEFAULT_OUTPUT_FILE_SUFFIX