OnlineStatus.java

public class OnlineStatus {
    private int recentOnlineThresholdDays;
    private int onlineThresholdHrs;

    public enum States {Unknown, Online, Recent}

    public void setOnlineThresholdHrs(int hours) {
        this.onlineThresholdHrs = hours;
    }

    public void setRecentOnlineThresholdDays(int days) {
        this.recentOnlineThresholdDays = days;
    }

    public States getStatus(Date lastOnline, Calendar calendar) {
        if (onlineThresholdHrs <= 0) {
            throw new IllegalArgumentException("Requires online threshold in hours");
        }

        int currentHour = calendar.get(Calendar.HOUR_OF_DAY);
        int currentDay = calendar.get(Calendar.DAY_OF_YEAR);

        States state = States.Unknown;

        calendar = Calendar.getInstance();
        calendar.set(
                Calendar.DAY_OF_YEAR,
                currentDay - recentOnlineThresholdDays
        );

        Date recentOnlineThreshold = calendar.getTime();
        if (lastOnline.after(recentOnlineThreshold)) {
            state = States.Recent;
        }


        calendar = Calendar.getInstance();
        calendar.set(
                Calendar.HOUR_OF_DAY,
                currentHour - onlineThresholdHrs);

        Date onlineThreshold = calendar.getTime();
        if (lastOnline.after(onlineThreshold)) {
            state = States.Online;
        }

        return state;
    }
}