| /* |
| * 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.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. */ |
| } |
| } |