import java.io.*;
import java.util.*;
import java.nio.file.*;
import java.util.regex.*;

public class CBFIni {

        public ArrayList<SectionFields> sectionData = new ArrayList<SectionFields>();
        Pattern patternParam = Pattern.compile("^[A-Za-z_0-9]+");
        Matcher matchParam, matchValue;
        String nameParam;

        public CBFIni() {

                try {

                        List<String> lines = Files.readAllLines(Paths.get("backups.conf"));
                        boolean checkSection = false;
                        int i = -1;

                        for(String line: lines){
                                if (line.length() > 0 && line.charAt(0) != '#') {
                                        if (!checkSection) {
                                                checkSection = true; // Отметка, что начались параметры секции
                                                sectionData.add(new SectionFields()); // Создаем новый элемент-объект списка
                                        }
                                        i++;
                                        matchParam = patternParam.matcher(line); // Выуживаем имя параметра
                                        if (matchParam.matches()) {
                                                nameParam = line.substring(matchParam.start(),matchParam.end()); // Имя параметра
                                                sectionData.get(sectionData.size()-1).(nameParam) = line.substring(matchParam.end()+1);
                                        }
                                } else {
                                        checkSection = false;
                                        i = -1;
                                }
                        }
                } catch (IOException e) {
                }
        }

        public class SectionFields {
                String backup, description, type, server, folder;
                int days, weeks, monthes, years, masterDay;
        }

}

sectionData.get(sectionData.size()-1).(nameParam) = line.substring(matchParam.end()+1);

private static void setValue(Class<?> type,
                             Object object,
                             String paramName,
                             String value) throws Exception {

    Field field;
    do {
        field = type.getDeclaredField(paramName);
        type = type.getSuperclass();
    } while (field != null && type != null);

    if (field == null)
        throw new IllegalArgumentException(
                          "can't find the field with name: " + paramName);

    field.setAccessible(true);
    field.set(object, value);
}

private static Map<String, MethodHandle> getSetters(Class<?> type) throws Exception {
    Map<String, MethodHandle> setters = new HashMap<>();
    while (type != null) {
        for (Field field : type.getDeclaredFields()) {
            field.setAccessible(true);
            setters.put(field.getName(), MethodHandles
                                                      .lookup()
                                                      .unreflectSetter(field));
        }
        type = type.getSuperclass();
    }

    return setters;
}

Map<String, MethodHandle> setters = getSetters(SectionFields.class);
SectionFields obj = new SectionFields();
setters.get("backup").invoke(obj, "hello world");