/*

 * Copyright (c) 2000, 2013, 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() getValue()}. A date-time attribute's

 * Date value is established when it is constructed (see {@link

 * #DateTimeSyntax(Date) DateTimeSyntax(Date)}). 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;

    }

}