written in browser, have no IDE there

IntervalType.java

// 

protected enum IntervalType {
    UNKNOWN(0),
    MINUTE(60, "minute", "m"),
    HOUR(3600, "hour", "h"),
    DAY(86400, "day", "d"),
    WEEK(604800, "week", "w"),
    MONTH(2592000, "month"),
    YEAR(31104000, "year");

    private final int value;

    private final String[] labels;

    private IntervalType(int seconds, String... labels) {
         // save into private final properties
         this.value = seconds;
         this.labels = labels;
    }

    public int value() {
         return this.value;
    }

    public String[] labels() {
         return this.labels;
    } 

    public static IntervalType byLabel(String label) {
         if(intervalMap.containsKey(label) {
              return intervalMap.get(label);
         } else {
              return UNKNOWN;
         }
    }

    private final static Map<String, IntervalType> intervalMap = new HashMap<String, IntervalType>();

    static {
        for(IntervalType type : IntervalType.values()) {
            for(String label : type.labels()) {
                intervalMap.put(label, type);
            }
        }
    }

}