Refactor QuietTimeChecker

import java.util.Calendar;

import java.util.GregorianCalendar;

class QuietTimeChecker {

    private final Clock clock;

    private final String quietTimeStart;

    private final String quietTimeEnd;

    private final int quietTimeStart;

    private final int quietTimeEnd;

    QuietTimeChecker(Clock clock, String quietTimeStart, String quietTimeEnd) {

        this.clock = clock;

        this.quietTimeStart = quietTimeStart;

        this.quietTimeEnd = quietTimeEnd;

        this.quietTimeStart = parseTime(quietTimeStart);

        this.quietTimeEnd = parseTime(quietTimeEnd);

    }

    public boolean isQuietTime() {

        GregorianCalendar gregorianCalendar = new GregorianCalendar();

        gregorianCalendar.setTimeInMillis(clock.getTime());

        Integer startHour = Integer.parseInt(quietTimeStart.split(":")[0]);

        Integer startMinute = Integer.parseInt(quietTimeStart.split(":")[1]);

        Integer endHour = Integer.parseInt(quietTimeEnd.split(":")[0]);

        Integer endMinute = Integer.parseInt(quietTimeEnd.split(":")[1]);

    private static int parseTime(String time) {

        String[] parts = time.split(":");

        int hour = Integer.parseInt(parts[0]);

        int minute = Integer.parseInt(parts[1]);

        Integer now = (gregorianCalendar.get(Calendar.HOUR_OF_DAY) * 60) + gregorianCalendar.get(Calendar.MINUTE);

        Integer quietStarts = startHour * 60 + startMinute;

        Integer quietEnds =  endHour * 60 + endMinute;

        return hour * 60 + minute;

    }

    public boolean isQuietTime() {

        // If start and end times are the same, we're never quiet

        if (quietStarts.equals(quietEnds)) {

        if (quietTimeStart == quietTimeEnd) {

            return false;

        }

        Calendar calendar = Calendar.getInstance();

        calendar.setTimeInMillis(clock.getTime());

        // 21:00 - 05:00 means we want to be quiet if it's after 9 or before 5

        if (quietStarts > quietEnds) {

            // if it's 22:00 or 03:00 but not 8:00

            if (now >= quietStarts || now <= quietEnds) {

        int minutesSinceMidnight = (calendar.get(Calendar.HOUR_OF_DAY) * 60) + calendar.get(Calendar.MINUTE);

        if (quietTimeStart > quietTimeEnd) {

            if (minutesSinceMidnight >= quietTimeStart || minutesSinceMidnight <= quietTimeEnd) {

                return true;

            }

        }

        // 01:00 - 05:00

        else {

            // if it' 2:00 or 4:00 but not 8:00 or 0:00

            if (now >= quietStarts && now <= quietEnds) {

        } else {

            if (minutesSinceMidnight >= quietTimeStart && minutesSinceMidnight <= quietTimeEnd) {

                return true;

            }

        }