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import java.util.Calendar;
import java.util.Date;
/**
* 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.
*/
/**
* <p>A suite of utilities surrounding the use of the
* {@link java.util.Calendar} and {@link java.util.Date} object.</p>
*
* <p>DateUtils contains a lot of common methods considering manipulations
* of Dates or Calendars. Some methods require some extra explanation.
* The truncate and round methods could be considered the Math.floor(),
* Math.ceil() or Math.round versions for dates
* This way date-fields will be ignored in bottom-up order.
* As a complement to these methods we've introduced some fragment-methods.
* With these methods the Date-fields will be ignored in top-down order.
* Since a date without a year is not a valid date, you have to decide in what
* kind of date-field you want your result, for instance milliseconds or days.
* </p>
*
*
*
* @author <a href="mailto:sergek@lokitech.com">Serge Knystautas</a>
* @author Stephen Colebourne
* @author Janek Bogucki
* @author <a href="mailto:ggregory@seagullsw.com">Gary Gregory</a>
* @author Phil Steitz
* @author Robert Scholte
* @since 2.0
* @version $Id: DateUtils.java 634096 2008-03-06 00:58:11Z niallp $
*/
public class Main {
//-----------------------------------------------------------------------
/**
* Sets the miliseconds field to a date returning a new object.
* The original date object is unchanged.
*
* @param date the date, not null
* @param amount the amount to set
* @return a new Date object set with the specified value
* @throws IllegalArgumentException if the date is null
* @since 2.4
*/
public static Date setMilliseconds(Date date, int amount) {
return set(date, Calendar.MILLISECOND, amount);
}
//-----------------------------------------------------------------------
/**
* Sets the specified field to a date returning a new object.
* This does not use a lenient calendar.
* The original date object is unchanged.
*
* @param date the date, not null
* @param calendarField the calendar field to set the amount to
* @param amount the amount to set
* @return a new Date object set with the specified value
* @throws IllegalArgumentException if the date is null
* @since 2.4
*/
private static Date set(Date date, int calendarField, int amount) {
if (date == null) {
throw new IllegalArgumentException("The date must not be null");
}
// getInstance() returns a new object, so this method is thread safe.
Calendar c = Calendar.getInstance();
c.setLenient(false);
c.setTime(date);
c.set(calendarField, amount);
return c.getTime();
}
}
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