/*
 * @(#)JobHoldUntil.java	1.4 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package javax.print.attribute.standard;

import java.util.Date;
import javax.print.attribute.DateTimeSyntax;
import javax.print.attribute.PrintRequestAttribute;
import javax.print.attribute.PrintJobAttribute;

/**
 * Class JobHoldUntil is a printing attribute class, a date-time attribute, that 
 * specifies the exact date and time at which the job must become a candidate 
 * for printing. 
 * <P>
 * If the value of this attribute specifies a date-time that is in the future, 
 * the printer should add the {@link JobStateReason JobStateReason} value of 
 * JOB_HOLD_UNTIL_SPECIFIED to the job's {@link JobStateReasons JobStateReasons} 
 * attribute, must move the job to the PENDING_HELD state, and must not schedule 
 * the job for printing until the specified date-time arrives. 
 * <P>
 * When the specified date-time arrives, the printer must remove the {@link 
 * JobStateReason JobStateReason} value of JOB_HOLD_UNTIL_SPECIFIED from the 
 * job's {@link JobStateReasons JobStateReasons} attribute, if present. If there 
 * are no other job state reasons that keep the job in the PENDING_HELD state, 
 * the printer must consider the job as a candidate for processing by moving the 
 * job to the PENDING state. 
 * <P>
 * If the specified date-time has already passed, the job must be a candidate 
 * for processing immediately. Thus, one way to make the job immediately become 
 * a candidate for processing is to specify a JobHoldUntil attribute constructed 
 * like this (denoting a date-time of January 1, 1970, 00:00:00 GMT): 
 * <PRE>
 *     JobHoldUntil immediately = new JobHoldUntil (new Date (0L));
 * </PRE>
 * <P>
 * If the client does not supply this attribute in a Print Request and the 
 * printer supports this attribute, the printer must use its 
 * (implementation-dependent) default JobHoldUntil value at job submission time 
 * (unlike most job template attributes that are used if necessary at job 
 * processing time). 
 * <P>
 * To construct a JobHoldUntil attribute from separate values of the year, 
 * month, day, hour, minute, and so on, use a {@link java.util.Calendar 
 * Calendar} object to construct a {@link java.util.Date Date} object, then use 
 * the {@link java.util.Date Date} object to construct the JobHoldUntil 
 * attribute. To convert a JobHoldUntil attribute to separate values of the 
 * year, month, day, hour, minute, and so on, create a {@link java.util.Calendar 
 * Calendar} object and set it to the {@link java.util.Date Date} from the 
 * JobHoldUntil attribute. 
 * <P>
 * <B>IPP Compatibility:</B> Although IPP supports a "job-hold-until" attribute 
 * specified as a keyword, IPP does not at this time support a "job-hold-until" 
 * attribute specified as a date and time. However, the date and time can be 
 * converted to one of the standard IPP keywords with some loss of precision; 
 * for example, a JobHoldUntil value with today's date and 9:00pm local time 
 * might be converted to the standard IPP keyword "night". The category name 
 * returned by <CODE>getName()</CODE> gives the IPP attribute name. 
 * <P>
 *
 * @author  Alan Kaminsky
 */
public final class JobHoldUntil extends DateTimeSyntax
	implements PrintRequestAttribute, PrintJobAttribute {

    /**
     * Construct a new job hold until date-time attribute with the given
     * {@link java.util.Date Date} value. 
     *
     * @param  dateTime  {@link java.util.Date Date} value.
     *
     * @exception  NullPointerException
     *     (unchecked exception) Thrown if <CODE>dateTime</CODE> is null.
     */
    public JobHoldUntil(Date dateTime) {
	super (dateTime);
    }

    /**
     * Returns whether this job hold until 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 JobHoldUntil.
     * <LI>
     * This job hold until attribute's {@link java.util.Date Date} value and 
     * <CODE>object</CODE>'s {@link java.util.Date Date} value are equal. 
     * </OL>
     *
     * @param  object  Object to compare to.
     *
     * @return  True if <CODE>object</CODE> is equivalent to this job hold
     *          until attribute, false otherwise. 
     */
    public boolean equals(Object object) {
	return (super.equals(object) && object instanceof JobHoldUntil);
    }


    /**
     * Get the printing attribute class which is to be used as the "category" 
     * for this printing attribute value.
     * <P>
     * For class JobHoldUntil, the category is class JobHoldUntil itself.
     *
     * @return  Printing attribute class (category), an instance of class
     *          {@link java.lang.Class java.lang.Class}.
     */
    public final Class getCategory() {
	return JobHoldUntil.class;
    }
    
    /**
     * Get the name of the category of which this attribute value is an 
     * instance. 
     * <P>
     * For class JobHoldUntil, the category name is <CODE>"job-hold-until"</CODE>. 
     *
     * @return  Attribute category name.
     */
    public final String getName() {
	return "job-hold-until";
    }
    
}