/*
* @(#)NotificationResult.java 1.6 03/12/19
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.management.remote;
import java.io.Serializable;
import javax.management.Notification;
import javax.management.ObjectName;
/**
* <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
* @since.unbundled 1.0
*/
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;
}
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