DateUtils.java

package pex.utils;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class DateUtils {
	protected final static Pattern INTERVAL_PATTERN = Pattern.compile("((?:\\d+)|(?:\\d+\\.\\d+))\\s*(second|minute|hour|day|week|month|year|s|m|h|d|w)", Pattern.CASE_INSENSITIVE);

	public static int parseInterval(String arg) {
		if (arg.matches("^\\d+$")) {
			return Integer.parseInt(arg);
		}

		Matcher match = INTERVAL_PATTERN.matcher(arg);

		int interval = 0;

		while (match.find()) {
			interval += Math.round(Float.parseFloat(match.group(1)) * getSecondsIn(match.group(2)));
		}

		return interval;
	}

	public static int getSecondsIn(String type) {
		type = type.toLowerCase();

		if ("second".equals(type) || "s".equals(type)) {
			return 1;
		} else if ("minute".equals(type) || "m".equals(type)) {
			return 60;
		} else if ("hour".equals(type) || "h".equals(type)) {
			return 3600;
		} else if ("day".equals(type) || "d".equals(type)) {
			return 86400;
		} else if ("week".equals(type) || "w".equals(type)) {
			return 604800;
		} else if ("month".equals(type)) {
			return 2592000;
		} else if ("year".equals(type)) {
			return 31104000;
		}

		return 0;
	}
}