org.dspace.content.DCDate Maven / Gradle / Ivy
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/**
* 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.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.TimeZone;
import org.apache.logging.log4j.Logger;
// FIXME: Not very robust - assumes dates will always be valid
/**
* Dublin Core date utility class
*
* 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.
*
* YYYY-MM-DDThh:mm:ss
*
* There are four levels of granularity, depending on how much date information
* is available: year, month, day, time.
*
* Examples: {@code 1994-05-03T15:30:24}, {@code 1995-10-04},
* {@code 2001-10}, {@code 1975}
*
* @author Robert Tansley
* @author Larry Stone
*/
public class DCDate {
/**
* Logger
*/
private static Logger log = org.apache.logging.log4j.LogManager.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 dfsLocaleMap = new HashMap();
/**
* Construct a date object from a Java Date object.
*
* @param date the Java Date 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.
*/
@Override
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";
}
}
}