/* ********************************************************************** **
** Copyright notice **
** **
** (c) 2005-2009 RSSOwl Development Team **
** http://www.rssowl.org/ **
** **
** All rights reserved **
** **
** This program and the accompanying materials are made available under **
** the terms of the Eclipse Public License v1.0 which accompanies this **
** distribution, and is available at: **
** http://www.rssowl.org/legal/epl-v10.html **
** **
** A copy is found in the file epl-v10.html and important notices to the **
** license from the team is found in the textfile LICENSE.txt distributed **
** in this package. **
** **
** This copyright notice MUST APPEAR in all copies of the file! **
** **
** Contributors: **
** RSSOwl Development Team - initial API and implementation **
** **
** ********************************************************************** */
package org.rssowl.core.util;
import org.eclipse.core.runtime.Assert;
import org.rssowl.core.persist.INews;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.TimeZone;
/**
* Utility Class for working with <code>Dates</code>.
*
* @author bpasero
*/
public class DateUtils {
/** 1 Day in Millis */
public static final long DAY = 24L * 60L * 60L * 1000L;
/** 1 Week in Millis */
public static final long WEEK = 7 * DAY;
/* An array of custom date formats */
private static final DateFormat[] CUSTOM_DATE_FORMATS;
/* The Default Timezone to be used */
private static final TimeZone TIMEZONE = TimeZone.getTimeZone("UTC"); //$NON-NLS-1$
/**
* @return A Calendar instance with the time being Today with a Time of
* 0:00:00
*/
public static Calendar getToday() {
Calendar today = Calendar.getInstance();
today.set(Calendar.HOUR_OF_DAY, 0);
today.set(Calendar.MINUTE, 0);
today.set(Calendar.SECOND, 0);
today.set(Calendar.MILLISECOND, 0);
return today;
}
/**
* Returns the first Date-Field from the given News that is not NULL. Tries
* Modified-Date, Publish-Date, and Received-Date. The latter one is never
* NULL so this Method will never return NULL at all.
*
* @param news The News to get the Date from.
* @return Either Modified-Date, Publish-Date or Received-Date if the formers
* are NULL.
*/
public static Date getRecentDate(INews news) {
if (news.getModifiedDate() != null)
return news.getModifiedDate();
if (news.getPublishDate() != null)
return news.getPublishDate();
return news.getReceiveDate();
}
/**
* Works like getRecentData(INews news) with the difference of returning the
* most recent date from a List of News.
*
* @param news A List of News to get the most recent Date from.
* @return Either Modified-Date, Publish-Date or Received-Date from the most
* recent News.
*/
public static Date getRecentDate(List<INews> news) {
Assert.isTrue(!news.isEmpty());
Date mostRecentDate = null;
for (INews newsitem : news) {
Date date = getRecentDate(newsitem);
if (mostRecentDate == null || date.after(mostRecentDate))
mostRecentDate = date;
}
return mostRecentDate;
}
/**
* Tries different date formats to parse against the given string
* representation to retrieve a valid Date object.
*
* @param strdate Date as String
* @return Date The parsed Date
*/
public static Date parseDate(String strdate) {
/* Return in case the string date is not set */
if (strdate == null || strdate.length() == 0)
return null;
Date result = null;
strdate = strdate.trim();
if (strdate.length() > 10) {
/* Open: deal with +4:00 (no zero before hour) */
if ((strdate.substring(strdate.length() - 5).indexOf("+") == 0 || strdate.substring(strdate.length() - 5).indexOf("-") == 0) && strdate.substring(strdate.length() - 5).indexOf(":") == 2) { //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
String sign = strdate.substring(strdate.length() - 5, strdate.length() - 4);
strdate = strdate.substring(0, strdate.length() - 5) + sign + "0" + strdate.substring(strdate.length() - 4); //$NON-NLS-1$
}
String dateEnd = strdate.substring(strdate.length() - 6);
/*
* try to deal with -05:00 or +02:00 at end of date replace with -0500 or
* +0200
*/
if ((dateEnd.indexOf("-") == 0 || dateEnd.indexOf("+") == 0) && dateEnd.indexOf(":") == 3) { //$NON-NLS-1$//$NON-NLS-2$ //$NON-NLS-3$
if (!"GMT".equals(strdate.substring(strdate.length() - 9, strdate.length() - 6))) { //$NON-NLS-1$
String oldDate = strdate;
String newEnd = dateEnd.substring(0, 3) + dateEnd.substring(4);
strdate = oldDate.substring(0, oldDate.length() - 6) + newEnd;
}
}
}
/* Try to parse the date */
int i = 0;
while (i < CUSTOM_DATE_FORMATS.length) {
try {
/*
* This Block needs to be synchronized, because the parse-Method in
* SimpleDateFormat is not Thread-Safe.
*/
synchronized (CUSTOM_DATE_FORMATS[i]) {
return CUSTOM_DATE_FORMATS[i].parse(strdate);
}
} catch (ParseException e) {
i++;
} catch (NumberFormatException e) {
i++;
}
}
return result;
}
/** Initialize the array of common date formats and formatter */
static {
/* Create Date Formats */
final String[] possibleDateFormats = {
/* RFC 1123 with 2-digit Year */
"EEE, dd MMM yy HH:mm:ss z", //$NON-NLS-1$
/* RFC 1123 with 4-digit Year */
"EEE, dd MMM yyyy HH:mm:ss z", //$NON-NLS-1$
/* RFC 1123 with no Timezone */
"EEE, dd MMM yy HH:mm:ss", //$NON-NLS-1$
/* Variant of RFC 1123 */
"EEE, MMM dd yy HH:mm:ss", //$NON-NLS-1$
/* RFC 1123 with no Seconds */
"EEE, dd MMM yy HH:mm z", //$NON-NLS-1$
/* Variant of RFC 1123 */
"EEE dd MMM yyyy HH:mm:ss", //$NON-NLS-1$
/* RFC 1123 with no Day */
"dd MMM yy HH:mm:ss z", //$NON-NLS-1$
/* RFC 1123 with no Day or Seconds */
"dd MMM yy HH:mm z", //$NON-NLS-1$
/* ISO 8601 slightly modified */
"yyyy-MM-dd'T'HH:mm:ssZ", //$NON-NLS-1$
/* ISO 8601 slightly modified */
"yyyy-MM-dd'T'HH:mm:ss'Z'", //$NON-NLS-1$
/* ISO 8601 slightly modified */
"yyyy-MM-dd'T'HH:mm:sszzzz", //$NON-NLS-1$
/* ISO 8601 slightly modified */
"yyyy-MM-dd'T'HH:mm:ss z", //$NON-NLS-1$
/* ISO 8601 */
"yyyy-MM-dd'T'HH:mm:ssz", //$NON-NLS-1$
/* ISO 8601 slightly modified */
"yyyy-MM-dd'T'HH:mm:ss.SSSz", //$NON-NLS-1$
/* ISO 8601 slightly modified */
"yyyy-MM-dd'T'HHmmss.SSSz", //$NON-NLS-1$
/* ISO 8601 slightly modified */
"yyyy-MM-dd'T'HH:mm:ss", //$NON-NLS-1$
/* ISO 8601 w/o seconds */
"yyyy-MM-dd'T'HH:mmZ", //$NON-NLS-1$
/* ISO 8601 w/o seconds */
"yyyy-MM-dd'T'HH:mm'Z'", //$NON-NLS-1$
/* RFC 1123 without Day Name */
"dd MMM yyyy HH:mm:ss z", //$NON-NLS-1$
/* RFC 1123 without Day Name and Seconds */
"dd MMM yyyy HH:mm z", //$NON-NLS-1$
/* Simple Date Format */
"yyyy-MM-dd", //$NON-NLS-1$
/* Simple Date Format */
"MMM dd, yyyy" //$NON-NLS-1$
};
/* Create the dateformats */
CUSTOM_DATE_FORMATS = new SimpleDateFormat[possibleDateFormats.length];
for (int i = 0; i < possibleDateFormats.length; i++) {
CUSTOM_DATE_FORMATS[i] = new SimpleDateFormat(possibleDateFormats[i], Locale.ENGLISH);
CUSTOM_DATE_FORMATS[i].setTimeZone(TIMEZONE);
}
}
}