/* * Copyright (c) 2003, 2007, 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.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) {        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.  */         this.earliestSequenceNumber = earliestSequenceNumber;        this.nextSequenceNumber = nextSequenceNumber;        this.targetedNotifications = targetedNotifications;    }     /**     * 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;    }     /**     * 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 final long earliestSequenceNumber;    private final long nextSequenceNumber;    private final TargetedNotification[] targetedNotifications;}