/* * Copyright (c) 2000, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */  package javax.print.attribute; import java.io.Serializable; import java.util.Date; /** * Class DateTimeSyntax is an abstract base class providing the common * implementation of all attributes whose value is a date and time. * <P> * Under the hood, a date-time attribute is stored as a value of class <code> * java.util.Date</code>. You can get a date-time attribute's Date value by * calling {@link #getValue() <CODE>getValue()</CODE>}. A date-time attribute's * Date value is established when it is constructed (see {@link * #DateTimeSyntax(Date) <CODE>DateTimeSyntax(Date)</CODE>}). Once * constructed, a date-time attribute's value is immutable. * <P> * To construct a date-time attribute from separate values of the year, month, * day, hour, minute, and so on, use a <code>java.util.Calendar</code> * object to construct a <code>java.util.Date</code> object, then use the * <code>java.util.Date</code> object to construct the date-time attribute. * To convert * a date-time attribute to separate values of the year, month, day, hour, * minute, and so on, create a <code>java.util.Calendar</code> object and * set it to the <code>java.util.Date</code> from the date-time attribute. Class * DateTimeSyntax stores its value in the form of a <code>java.util.Date * </code> * rather than a <code>java.util.Calendar</code> because it typically takes * less memory to store and less time to compare a <code>java.util.Date</code> * than a <code>java.util.Calendar</code>. * <P> * * @author  Alan Kaminsky */public abstract class DateTimeSyntax implements Serializable, Cloneable {     private static final long serialVersionUID = -1400819079791208582L;     // Hidden data members.     /**     * This date-time attribute's<code>java.util.Date</code> value.     * @serial     */    private Date value;     // Hidden constructors.     /**     * Construct a new date-time attribute with the given     * <code>java.util.Date </code> value.     *     * @param  value   <code>java.util.Date</code> value.     *     * @exception  NullPointerException     *     (unchecked exception) Thrown if <CODE>theValue</CODE> is null.     */    protected DateTimeSyntax(Date value) {        if (value == null) {            throw new NullPointerException("value is null");        }        this.value = value;    }     // Exported operations.     /**     * Returns this date-time attribute's <code>java.util.Date</code>     * value.     * @return the Date.     */    public Date getValue() {        return new Date (value.getTime());    }     // Exported operations inherited and overridden from class Object.     /**     * Returns whether this date-time attribute is equivalent to the passed in     * object. To be equivalent, all of the following conditions must be true:     * <OL TYPE=1>     * <LI>     * <CODE>object</CODE> is not null.     * <LI>     * <CODE>object</CODE> is an instance of class DateTimeSyntax.     * <LI>     * This date-time attribute's <code>java.util.Date</code> value and     * <CODE>object</CODE>'s <code>java.util.Date</code> value are     * equal. </OL>     *     * @param  object  Object to compare to.     *     * @return  True if <CODE>object</CODE> is equivalent to this date-time     *          attribute, false otherwise.     */    public boolean equals(Object object) {        return (object != null &&                object instanceof DateTimeSyntax &&                value.equals(((DateTimeSyntax) object).value));    }     /**     * Returns a hash code value for this date-time attribute. The hashcode is     * that of this attribute's <code>java.util.Date</code> value.     */    public int hashCode() {        return value.hashCode();    }     /**     * Returns a string value corresponding to this date-time attribute.     * The string value is just this attribute's     * <code>java.util.Date</code>  value     * converted to a string.     */    public String toString() {        return "" + value;    } }