Main.java Source code

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Here is the source code for Main.java

Source

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 years 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 setYears(Date date, int amount) {
        return set(date, Calendar.YEAR, 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();
    }
}