Method parseDuration

src/utils/DateTime.java:187–231

Parses a human-readable duration (e.g, "10m", "3h", "14d") into seconds. Formats supported: ms: milliseconds s: seconds m: minutes h: hours d: days w: weeks n: month (30 days)</l

(final String duration)

   * @throws IllegalArgumentException if the interval was malformed.
   */
  public static final long parseDuration(final String duration) {
    if (duration == null || duration.isEmpty()) {
      throw new IllegalArgumentException("Cannot parse null or empty duration");
    }

    long interval;
    long multiplier;
    double temp;
    int unit = 0;
    while (Character.isDigit(duration.charAt(unit))) {
      unit++;
      if (unit >= duration.length()) {
        throw new IllegalArgumentException("Invalid duration, must have an "
            + "integer and unit: " + duration);
      }
    }
    try {
      interval = Long.parseLong(duration.substring(0, unit));
    } catch (NumberFormatException e) {
      throw new IllegalArgumentException("Invalid duration (number): " + duration);
    }
    if (interval <= 0) {
      throw new IllegalArgumentException("Zero or negative duration: " + duration);
    }
    switch (duration.toLowerCase().charAt(duration.length() - 1)) {
      case 's': 
        if (duration.charAt(duration.length() - 2) == 'm') {
          return interval;
        }
        multiplier = 1; break;                        // seconds
      case 'm': multiplier = 60; break;               // minutes
      case 'h': multiplier = 3600; break;             // hours
      case 'd': multiplier = 3600 * 24; break;        // days
      case 'w': multiplier = 3600 * 24 * 7; break;    // weeks
      case 'n': multiplier = 3600 * 24 * 30; break;   // month (average)
      case 'y': multiplier = 3600 * 24 * 365; break;  // years (screw leap years)
      default: throw new IllegalArgumentException("Invalid duration (suffix): " + duration);
    }
    multiplier *= 1000;
    temp = (double)interval * multiplier;
    if (temp > Long.MAX_VALUE) {
      throw new IllegalArgumentException("Duration must be < Long.MAX_VALUE ms: " + duration);
    }
    return interval * multiplier;
  }

  /**
   * Returns the suffix or "units" of the duration as a string. The result will