001package com.box.sdk;
002
003import java.text.DateFormat;
004import java.text.ParseException;
005import java.text.SimpleDateFormat;
006import java.util.Date;
007
008/**
009 * Contains methods for parsing and formatting dates for use with the Box API.
010 */
011public final class BoxDateFormat {
012    private static final ThreadLocal<DateFormat> THREAD_LOCAL_DATE_FORMAT = new ThreadLocal<DateFormat>() {
013        @Override
014        protected DateFormat initialValue() {
015            return new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");
016        }
017    };
018
019    private BoxDateFormat() { }
020
021    /**
022     * Parses a date string returned by the Box API into a {@link Date} object.
023     * @param  dateString     a string containing the date.
024     * @return                the parsed date.
025     * @throws ParseException if the string cannot be parsed into a valid date.
026     */
027    public static Date parse(String dateString) throws ParseException {
028        return THREAD_LOCAL_DATE_FORMAT.get().parse(fixIso8601TimeZone(dateString));
029    }
030
031    /**
032     * Formats a date as a string that can be sent to the Box API.
033     * @param  date the date to format.
034     * @return      a string containing the formatted date.
035     */
036    public static String format(Date date) {
037        return THREAD_LOCAL_DATE_FORMAT.get().format(date);
038    }
039
040    /**
041     * Helper function to handle ISO 8601 strings of the following format:
042     * "2008-03-01T13:00:00+01:00".  Note that the final colon (":") in the
043     * time zone is not supported by SimpleDateFormat's "Z" token.
044     *
045     * @param dateString a string containing the date.
046     * @return a date string that matches the date format.
047     */
048    private static String fixIso8601TimeZone(String dateString) {
049        if (dateString.length() >= 24 && dateString.charAt(22) == ':') {
050            return dateString.substring(0, 22) + dateString.substring(23);
051        }
052        return dateString;
053    }
054}