/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.tools.ant.util;
import java.text.ChoiceFormat;
import java.text.DateFormat;
import java.text.MessageFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;
/**
* Helper methods to deal with date/time formatting with a specific
* defined format (<a href="http://www.w3.org/TR/NOTE-datetime">ISO8601</a>)
* or a plurialization correct elapsed time in minutes and seconds.
*
* @since Ant 1.5
*
*/
public final class DateUtils {
/**
* ISO8601-like pattern for date-time. It does not support timezone.
* <tt>yyyy-MM-ddTHH:mm:ss</tt>
*/
public static final String ISO8601_DATETIME_PATTERN
= "yyyy-MM-dd'T'HH:mm:ss";
/**
* ISO8601-like pattern for date. <tt>yyyy-MM-dd</tt>
*/
public static final String ISO8601_DATE_PATTERN
= "yyyy-MM-dd";
/**
* ISO8601-like pattern for time. <tt>HH:mm:ss</tt>
*/
public static final String ISO8601_TIME_PATTERN
= "HH:mm:ss";
/**
* Format used for SMTP (and probably other) Date headers.
*/
public static final DateFormat DATE_HEADER_FORMAT
= new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss ", Locale.US);
// code from Magesh moved from DefaultLogger and slightly modified
private static final MessageFormat MINUTE_SECONDS
= new MessageFormat("{0}{1}");
private static final double[] LIMITS = {0, 1, 2};
private static final String[] MINUTES_PART = {"", "1 minute ", "{0,number} minutes "};
private static final String[] SECONDS_PART = {"0 seconds", "1 second", "{1,number} seconds"};
private static final ChoiceFormat MINUTES_FORMAT =
new ChoiceFormat(LIMITS, MINUTES_PART);
private static final ChoiceFormat SECONDS_FORMAT =
new ChoiceFormat(LIMITS, SECONDS_PART);
static {
MINUTE_SECONDS.setFormat(0, MINUTES_FORMAT);
MINUTE_SECONDS.setFormat(1, SECONDS_FORMAT);
}
/** private constructor */
private DateUtils() {
}
/**
* Format a date/time into a specific pattern.
* @param date the date to format expressed in milliseconds.
* @param pattern the pattern to use to format the date.
* @return the formatted date.
*/
public static String format(long date, String pattern) {
return format(new Date(date), pattern);
}
/**
* Format a date/time into a specific pattern.
* @param date the date to format expressed in milliseconds.
* @param pattern the pattern to use to format the date.
* @return the formatted date.
*/
public static String format(Date date, String pattern) {
DateFormat df = createDateFormat(pattern);
return df.format(date);
}
/**
* Format an elapsed time into a plurialization correct string.
* It is limited only to report elapsed time in minutes and
* seconds and has the following behavior.
* <ul>
* <li>minutes are not displayed when 0. (ie: "45 seconds")</li>
* <li>seconds are always displayed in plural form (ie "0 seconds" or
* "10 seconds") except for 1 (ie "1 second")</li>
* </ul>
* @param millis the elapsed time to report in milliseconds.
* @return the formatted text in minutes/seconds.
*/
public static String formatElapsedTime(long millis) {
long seconds = millis / 1000;
long minutes = seconds / 60;
Object[] args = {new Long(minutes), new Long(seconds % 60)};
return MINUTE_SECONDS.format(args);
}
/**
* return a lenient date format set to GMT time zone.
* @param pattern the pattern used for date/time formatting.
* @return the configured format for this pattern.
*/
private static DateFormat createDateFormat(String pattern) {
SimpleDateFormat sdf = new SimpleDateFormat(pattern);
TimeZone gmt = TimeZone.getTimeZone("GMT");
sdf.setTimeZone(gmt);
sdf.setLenient(true);
return sdf;
}
/**
* Calculate the phase of the moon for a given date.
*
* <p>Code heavily influenced by hacklib.c in <a
* href="http://www.nethack.org/">Nethack</a></p>
*
* <p>The Algorithm:
*
* <pre>
* moon period = 29.53058 days ~= 30, year = 365.2422 days
*
* days moon phase advances on first day of year compared to preceding year
* = 365.2422 - 12*29.53058 ~= 11
*
* years in Metonic cycle (time until same phases fall on the same days of
* the month) = 18.6 ~= 19
*
* moon phase on first day of year (epact) ~= (11*(year%19) + 18) % 30
* (18 as initial condition for 1900)
*
* current phase in days = first day phase + days elapsed in year
*
* 6 moons ~= 177 days
* 177 ~= 8 reported phases * 22
* + 11/22 for rounding
* </pre>
*
* @param cal the calander.
*
* @return The phase of the moon as a number between 0 and 7 with
* 0 meaning new moon and 4 meaning full moon.
*
* @since 1.2, Ant 1.5
*/
public static int getPhaseOfMoon(Calendar cal) {
int dayOfTheYear = cal.get(Calendar.DAY_OF_YEAR);
int yearInMetonicCycle = ((cal.get(Calendar.YEAR) - 1900) % 19) + 1;
int epact = (11 * yearInMetonicCycle + 18) % 30;
if ((epact == 25 && yearInMetonicCycle > 11) || epact == 24) {
epact++;
}
return (((((dayOfTheYear + epact) * 6) + 11) % 177) / 22) & 7;
}
/**
* Returns the current Date in a format suitable for a SMTP date
* header.
* @return the current date.
* @since Ant 1.5.2
*/
public static String getDateForHeader() {
Calendar cal = Calendar.getInstance();
TimeZone tz = cal.getTimeZone();
int offset = tz.getOffset(cal.get(Calendar.ERA),
cal.get(Calendar.YEAR),
cal.get(Calendar.MONTH),
cal.get(Calendar.DAY_OF_MONTH),
cal.get(Calendar.DAY_OF_WEEK),
cal.get(Calendar.MILLISECOND));
StringBuffer tzMarker = new StringBuffer(offset < 0 ? "-" : "+");
offset = Math.abs(offset);
int hours = offset / (60 * 60 * 1000);
int minutes = offset / (60 * 1000) - 60 * hours;
if (hours < 10) {
tzMarker.append("0");
}
tzMarker.append(hours);
if (minutes < 10) {
tzMarker.append("0");
}
tzMarker.append(minutes);
return DATE_HEADER_FORMAT.format(cal.getTime()) + tzMarker.toString();
}
/**
* Parse a string as a datetime using the ISO8601_DATETIME format which is
* <code>yyyy-MM-dd'T'HH:mm:ss</code>
*
* @param datestr string to be parsed
*
* @return a java.util.Date object as parsed by the format.
* @exception ParseException if the supplied string cannot be parsed by
* this pattern.
* @since Ant 1.6
*/
public static Date parseIso8601DateTime(String datestr)
throws ParseException {
return new SimpleDateFormat(ISO8601_DATETIME_PATTERN).parse(datestr);
}
/**
* Parse a string as a date using the ISO8601_DATE format which is
* <code>yyyy-MM-dd</code>
*
* @param datestr string to be parsed
*
* @return a java.util.Date object as parsed by the format.
* @exception ParseException if the supplied string cannot be parsed by
* this pattern.
* @since Ant 1.6
*/
public static Date parseIso8601Date(String datestr) throws ParseException {
return new SimpleDateFormat(ISO8601_DATE_PATTERN).parse(datestr);
}
/**
* Parse a string as a date using the either the ISO8601_DATETIME
* or ISO8601_DATE formats.
*
* @param datestr string to be parsed
*
* @return a java.util.Date object as parsed by the formats.
* @exception ParseException if the supplied string cannot be parsed by
* either of these patterns.
* @since Ant 1.6
*/
public static Date parseIso8601DateTimeOrDate(String datestr)
throws ParseException {
try {
return parseIso8601DateTime(datestr);
} catch (ParseException px) {
return parseIso8601Date(datestr);
}
}
}
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