/**
* The contents of this file are subject to the license and copyright
* detailed in the LICENSE and NOTICE files at the root of the source
* tree and available online at
*
* http://www.dspace.org/license/
*/
package org.dspace.content;
import java.text.DateFormatSymbols;
import java.text.SimpleDateFormat;
import java.text.ParseException;
import java.util.*;
import org.apache.log4j.Logger;
// FIXME: Not very robust - assumes dates will always be valid
/**
* Dublin Core date utility class
* <P>
* Dates in the DSpace database are held in the ISO 8601 format. They are always
* stored in UTC, converting to and from the current time zone. In practice only dates
* with a time component need to be converted.
* <P>
* <code>YYYY-MM-DDThh:mm:ss</code>
* <P>
* There are four levels of granularity, depending on how much date information
* is available: year, month, day, time.
* <P>
* Examples: <code>1994-05-03T15:30:24</code>,<code>1995-10-04</code>,
* <code>2001-10</code>,<code>1975</code>
*
* @author Robert Tansley
* @author Larry Stone
* @version $Revision$
*/
public class DCDate
{
/** Logger */
private static Logger log = Logger.getLogger(DCDate.class);
// UTC timezone
private static final TimeZone utcZone = TimeZone.getTimeZone("UTC");
// components of time in UTC
private GregorianCalendar calendar = null;
// components of time in local zone
private GregorianCalendar localCalendar = null;
private enum DateGran { YEAR, MONTH, DAY, TIME }
DateGran granularity = null;
// Full ISO 8601 is e.g. "2009-07-16T13:59:21Z"
private final SimpleDateFormat fullIso = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
// without Z
private final SimpleDateFormat fullIso2 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
// without seconds
private final SimpleDateFormat fullIso3 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm");
// without minutes
private final SimpleDateFormat fullIso4 = new SimpleDateFormat("yyyy-MM-dd'T'HH");
// Date-only ISO 8601 is e.g. "2009-07-16"
private final SimpleDateFormat dateIso = new SimpleDateFormat("yyyy-MM-dd");
// Year-Month-only ISO 8601 is e.g. "2009-07"
private final SimpleDateFormat yearMonthIso = new SimpleDateFormat("yyyy-MM");
// just year, "2009"
private final SimpleDateFormat yearIso = new SimpleDateFormat("yyyy");
private static Map<Locale, DateFormatSymbols> dfsLocaleMap = new HashMap<Locale, DateFormatSymbols>();
/**
* Construct a date object from a Java <code>Date</code> object.
*
* @param date
* the Java <code>Date</code> object.
*/
public DCDate(Date date)
{
setUTCForFormatting();
if (date == null)
{
return;
}
// By definition a Date has a time component so always set the granularity to TIME.
granularity = DateGran.TIME;
// Set the local calendar.
localCalendar = new GregorianCalendar();
localCalendar.setTime(date);
// Now set the UTC equivalent.
calendar = new GregorianCalendar(utcZone);
calendar.setTime(date);
}
/**
* Construct a date object from a bunch of component parts. The date passed in is assumed to be in the current
* time zone. Unknown values should be given as -1.
*
* @param yyyy
* the year
* @param mm
* the month
* @param dd
* the day
* @param hh
* the hours
* @param mn
* the minutes
* @param ss
* the seconds
*/
public DCDate(int yyyy, int mm, int dd, int hh, int mn, int ss)
{
setUTCForFormatting();
// default values
int lyear = 0;
int lhours = 0;
int lminutes = 0;
int lseconds = 0;
int lmonth = 1;
int lday = 1;
if (yyyy > 0)
{
lyear = yyyy;
granularity = DateGran.YEAR;
}
if (mm > 0)
{
lmonth = mm;
granularity = DateGran.MONTH;
}
if (dd > 0)
{
lday = dd;
granularity = DateGran.DAY;
}
if (hh >= 0)
{
lhours = hh;
granularity = DateGran.TIME;
}
if (mn >= 0)
{
lminutes = mn;
granularity = DateGran.TIME;
}
if (ss >= 0)
{
lseconds = ss;
granularity = DateGran.TIME;
}
// Set the local calendar.
localCalendar = new GregorianCalendar(lyear, lmonth - 1, lday,
lhours, lminutes, lseconds);
if (granularity == DateGran.TIME)
{
// Now set the UTC equivalent.
calendar = new GregorianCalendar(utcZone);
calendar.setTime(localCalendar.getTime());
}
else
{
// No Time component so just set the UTC date to be the same as the local Year, Month, and Day.
calendar = new GregorianCalendar(localCalendar.get(Calendar.YEAR), localCalendar.get(Calendar.MONTH), localCalendar.get(Calendar.DAY_OF_MONTH));
}
}
/**
* Construct a date from a Dublin Core value
*
* @param fromDC
* the date string, in ISO 8601 (no timezone, always use UTC)
*/
public DCDate(String fromDC)
{
setUTCForFormatting();
// An empty date is OK
if ((fromDC == null) || fromDC.equals(""))
{
return;
}
// default granularity
granularity = DateGran.TIME;
Date date = tryParse(fullIso, fromDC);
if (date == null)
{
date = tryParse(fullIso2, fromDC);
}
if (date == null)
{
date = tryParse(fullIso3, fromDC);
}
if (date == null)
{
date = tryParse(fullIso4, fromDC);
}
if (date == null)
{
// Seems there is no time component to the date.
date = tryParse(dateIso, fromDC);
if (date != null)
{
granularity = DateGran.DAY;
}
}
if (date == null)
{
date = tryParse(yearMonthIso, fromDC);
if (date != null)
{
granularity = DateGran.MONTH;
}
}
if (date == null)
{
date = tryParse(yearIso, fromDC);
if (date != null)
{
granularity = DateGran.YEAR;
}
}
if (date == null)
{
log.warn("Mangled date: " + fromDC + " ..failed all attempts to parse as date.");
}
else
{
// Set the UTC time.
calendar = new GregorianCalendar(utcZone);
calendar.setTime(date);
// Now set the local equivalent.
if (granularity == DateGran.TIME)
{
localCalendar = new GregorianCalendar();
localCalendar.setTime(date);
}
else
{
// No Time component so just set the local date to be the same as the UTC Year, Month, and Day.
localCalendar = new GregorianCalendar(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH));
}
}
}
/**
* Set all the formatters to use UTC. SimpleDateFormat is not thread-safe which
* is why they are not static variables initialised once.
*/
private void setUTCForFormatting()
{
fullIso.setTimeZone(utcZone);
fullIso2.setTimeZone(utcZone);
fullIso3.setTimeZone(utcZone);
fullIso4.setTimeZone(utcZone);
dateIso.setTimeZone(utcZone);
yearMonthIso.setTimeZone(utcZone);
yearIso.setTimeZone(utcZone);
}
// Attempt to parse, swallowing errors; return null for failure.
private synchronized Date tryParse(SimpleDateFormat sdf, String source)
{
try
{
return sdf.parse(source);
}
catch (ParseException pe)
{
return null;
}
}
/**
* Get the year, adjusting for current time zone.
*
* @return the year
*/
public int getYear()
{
return (!withinGranularity(DateGran.YEAR)) ? -1 : localCalendar.get(Calendar.YEAR);
}
/**
* Get the month, adjusting for current time zone.
*
* @return the month
*/
public int getMonth()
{
return (!withinGranularity(DateGran.MONTH)) ? -1 : localCalendar.get(Calendar.MONTH) + 1;
}
/**
* Get the day, adjusting for current time zone.
*
* @return the day
*/
public int getDay()
{
return (!withinGranularity(DateGran.DAY)) ? -1 : localCalendar.get(Calendar.DAY_OF_MONTH);
}
/**
* Get the hour, adjusting for current time zone.
*
* @return the hour
*/
public int getHour()
{
return (!withinGranularity(DateGran.TIME)) ? -1 : localCalendar.get(Calendar.HOUR_OF_DAY);
}
/**
* Get the minute, adjusting for current time zone.
*
* @return the minute
*/
public int getMinute()
{
return (!withinGranularity(DateGran.TIME)) ? -1 : localCalendar.get(Calendar.MINUTE);
}
/**
* Get the second, adjusting for current time zone.
*
* @return the second
*/
public int getSecond()
{
return (!withinGranularity(DateGran.TIME)) ? -1 : localCalendar.get(Calendar.SECOND);
}
/**
* Get the year in UTC.
*
* @return the year
*/
public int getYearUTC()
{
return (!withinGranularity(DateGran.YEAR)) ? -1 : calendar.get(Calendar.YEAR);
}
/**
* Get the month in UTC.
*
* @return the month
*/
public int getMonthUTC()
{
return (!withinGranularity(DateGran.MONTH)) ? -1 : calendar.get(Calendar.MONTH) + 1;
}
/**
* Get the day in UTC.
*
* @return the day
*/
public int getDayUTC()
{
return (!withinGranularity(DateGran.DAY)) ? -1 : calendar.get(Calendar.DAY_OF_MONTH);
}
/**
* Get the hour in UTC.
*
* @return the hour
*/
public int getHourUTC()
{
return (!withinGranularity(DateGran.TIME)) ? -1 : calendar.get(Calendar.HOUR_OF_DAY);
}
/**
* Get the minute in UTC.
*
* @return the minute
*/
public int getMinuteUTC()
{
return (!withinGranularity(DateGran.TIME)) ? -1 : calendar.get(Calendar.MINUTE);
}
/**
* Get the second in UTC.
*
* @return the second
*/
public int getSecondUTC()
{
return (!withinGranularity(DateGran.TIME)) ? -1 : calendar.get(Calendar.SECOND);
}
/**
* Get the date as a string to put back in the Dublin Core. Use the UTC/GMT calendar version.
*
* @return The date as a string.
*/
public String toString()
{
if (calendar == null)
{
return "null";
}
return toStringInternal();
}
private synchronized String toStringInternal()
{
if (granularity == DateGran.YEAR)
{
return String.format("%4d", getYearUTC());
}
else if (granularity == DateGran.MONTH)
{
return String.format("%4d-%02d", getYearUTC(), getMonthUTC());
}
else if (granularity == DateGran.DAY)
{
return String.format("%4d-%02d-%02d", getYearUTC(), getMonthUTC(), getDayUTC());
}
else
{
return fullIso.format(calendar.getTime());
}
}
/**
* Get the date as a Java Date object.
*
* @return a Date object
*/
public Date toDate()
{
if (calendar == null)
{
return null;
}
else
{
return calendar.getTime();
}
}
/**
* Format a human-readable version of the DCDate, with optional time.
* This needs to be in DCDate because it depends on the granularity of
* the original time.
*
* FIXME: This should probably be replaced with a localized DateFormat.
*
* @param showTime
* if true, display the time with the date
* @param isLocalTime
* if true, adjust for local time zone, otherwise UTC
* @param locale
* locale of the user
*
* @return String with the date in a human-readable form.
*/
public String displayDate(boolean showTime, boolean isLocalTime, Locale locale)
{
if (isLocalTime)
{
return displayLocalDate(showTime, locale);
}
else
{
return displayUTCDate(showTime, locale);
}
}
public String displayLocalDate(boolean showTime, Locale locale)
{
// forcibly truncate month name to 3 chars -- XXX FIXME?
String monthName = getMonthName(getMonth(), locale);
if (monthName.length() > 2)
monthName = monthName.substring(0, 3);
// display date and time
if (showTime && granularity == DateGran.TIME)
{
return String.format("%d-%s-%4d %02d:%02d:%02d", getDay(), monthName, getYear(), getHour(), getMinute(), getSecond());
}
else if (granularity == DateGran.YEAR)
{
return String.format("%4d", getYear());
}
else if (granularity == DateGran.MONTH)
{
return String.format("%s-%4d", monthName, getYear());
}
else
{
return String.format("%d-%s-%4d", getDay(), monthName, getYear());
}
}
public String displayUTCDate(boolean showTime, Locale locale)
{
// forcibly truncate month name to 3 chars -- XXX FIXME?
String monthName = getMonthName(getMonthUTC(), locale);
if (monthName.length() > 2)
monthName = monthName.substring(0, 3);
// display date and time
if (showTime && granularity == DateGran.TIME)
{
return String.format("%d-%s-%4d %02d:%02d:%02d", getDayUTC(), monthName, getYearUTC(), getHourUTC(), getMinuteUTC(), getSecondUTC());
}
else if (granularity == DateGran.YEAR)
{
return String.format("%4d", getYearUTC());
}
else if (granularity == DateGran.MONTH)
{
return String.format("%s-%4d", monthName, getYearUTC());
}
else
{
return String.format("%d-%s-%4d", getDayUTC(), monthName, getYearUTC());
}
}
/**
* Test if the requested level of granularity is within that of the date.
*
* @param dg
* The requested level of granularity.
* @return
* true or false.
*
*/
private boolean withinGranularity(DateGran dg)
{
if (granularity == DateGran.TIME)
{
if ((dg == DateGran.TIME) || (dg == DateGran.DAY) || (dg == DateGran.MONTH) || (dg == DateGran.YEAR))
{
return true;
}
}
if (granularity == DateGran.DAY)
{
if ((dg == DateGran.DAY) || (dg == DateGran.MONTH) || (dg == DateGran.YEAR))
{
return true;
}
}
if (granularity == DateGran.MONTH)
{
if ((dg == DateGran.MONTH) || (dg == DateGran.YEAR))
{
return true;
}
}
if (granularity == DateGran.YEAR)
{
if (dg == DateGran.YEAR)
{
return true;
}
}
return false;
}
/************** Some utility methods ******************/
/**
* Get a date representing the current instant in time.
*
* @return a DSpaceDate object representing the current instant.
*/
public static DCDate getCurrent()
{
return (new DCDate(new Date()));
}
/**
* Get a month's name for a month between 1 and 12. Any invalid month value
* (e.g. 0 or -1) will return a value of "Unspecified".
*
* @param m
* the month number
* @param locale
* which locale to render the month name in
* @return the month name.
*/
public static String getMonthName(int m, Locale locale)
{
if ((m > 0) && (m < 13))
{
DateFormatSymbols dfs = dfsLocaleMap.get(locale);
if (dfs == null)
{
dfs = new DateFormatSymbols(locale);
dfsLocaleMap.put(locale, dfs);
}
return dfs.getMonths()[m-1];
}
else
{
return "Unspecified";
}
}
}