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	/*
	* Copyright (c) 2003, 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.management.remote;

	import java.io.IOException;
	import java.io.InvalidObjectException;
	import java.io.ObjectInputStream;
	import java.io.Serializable;

	/**
	* <p>Result of a query for buffered notifications. Notifications in
	* a notification buffer have positive, monotonically increasing
	* sequence numbers. The result of a notification query contains the
	* following elements:</p>
	*
	* <ul>
	*
	* <li>The sequence number of the earliest notification still in
	* the buffer.
	*
	* <li>The sequence number of the next notification available for
	* querying. This will be the starting sequence number for the next
	* notification query.
	*
	* <li>An array of (Notification,listenerID) pairs corresponding to
	* the returned notifications and the listeners they correspond to.
	*
	* </ul>
	*
	* <p>It is possible for the <code>nextSequenceNumber</code> to be less
	* than the <code>earliestSequenceNumber</code>. This signifies that
	* notifications between the two might have been lost.</p>
	*
	* @since 1.5
	*/
	public class NotificationResult implements Serializable {

	private static final long serialVersionUID = 1191800228721395279L;

	/**
	* <p>Constructs a notification query result.</p>
	*
	* @param earliestSequenceNumber the sequence number of the
	* earliest notification still in the buffer.
	* @param nextSequenceNumber the sequence number of the next
	* notification available for querying.
	* @param targetedNotifications the notifications resulting from
	* the query, and the listeners they correspond to. This array
	* can be empty.
	*
	* @exception IllegalArgumentException if
	* <code>targetedNotifications</code> is null or if
	* <code>earliestSequenceNumber</code> or
	* <code>nextSequenceNumber</code> is negative.
	*/
	public NotificationResult(long earliestSequenceNumber,
	long nextSequenceNumber,
	TargetedNotification[] targetedNotifications) {
	validate(targetedNotifications, earliestSequenceNumber, nextSequenceNumber);
	this.earliestSequenceNumber = earliestSequenceNumber;
	this.nextSequenceNumber = nextSequenceNumber;
	this.targetedNotifications = (targetedNotifications.length == 0 ? targetedNotifications : targetedNotifications.clone());
	}

	/**
	* Returns the sequence number of the earliest notification still
	* in the buffer.
	*
	* @return the sequence number of the earliest notification still
	* in the buffer.
	*/
	public long getEarliestSequenceNumber() {
	return earliestSequenceNumber;
	}

	/**
	* Returns the sequence number of the next notification available
	* for querying.
	*
	* @return the sequence number of the next notification available
	* for querying.
	*/
	public long getNextSequenceNumber() {
	return nextSequenceNumber;
	}

	/**
	* Returns the notifications resulting from the query, and the
	* listeners they correspond to.
	*
	* @return the notifications resulting from the query, and the
	* listeners they correspond to. This array can be empty.
	*/
	public TargetedNotification[] getTargetedNotifications() {
	return targetedNotifications.length == 0 ? targetedNotifications : targetedNotifications.clone();
	}

	/**
	* Returns a string representation of the object. The result
	* should be a concise but informative representation that is easy
	* for a person to read.
	*
	* @return a string representation of the object.
	*/
	public String toString() {
	return "NotificationResult: earliest=" + getEarliestSequenceNumber() +
	"; next=" + getNextSequenceNumber() + "; nnotifs=" +
	getTargetedNotifications().length;
	}

	private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
	ois.defaultReadObject();
	try {
	validate(
	this.targetedNotifications,
	this.earliestSequenceNumber,
	this.nextSequenceNumber
	);

	this.targetedNotifications = this.targetedNotifications.length == 0 ?
	this.targetedNotifications :
	this.targetedNotifications.clone();
	} catch (IllegalArgumentException e) {
	throw new InvalidObjectException(e.getMessage());
	}
	}

	private long earliestSequenceNumber;
	private long nextSequenceNumber;
	private TargetedNotification[] targetedNotifications;

	private static void validate(TargetedNotification[] targetedNotifications,
	long earliestSequenceNumber,
	long nextSequenceNumber)
	throws IllegalArgumentException {
	if (targetedNotifications == null) {
	final String msg = "Notifications null";
	throw new IllegalArgumentException(msg);
	}

	if (earliestSequenceNumber < 0 \|\| nextSequenceNumber < 0)
	throw new IllegalArgumentException("Bad sequence numbers");
	/* We used to check nextSequenceNumber >= earliestSequenceNumber
	here. But in fact the opposite can legitimately be true if
	notifications have been lost. */
	}
	}

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