| /* |
| * Copyright (c) 2003, 2017, 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 java.lang.management; |
| import javax.management.openmbean.CompositeData; |
| import sun.management.MemoryNotifInfoCompositeData; |
| |
| /** |
| * The information about a memory notification. |
| * |
| * <p> |
| * A memory notification is emitted by {@link MemoryMXBean} |
| * when the Java virtual machine detects that the memory usage |
| * of a memory pool is exceeding a threshold value. |
| * The notification emitted will contain the memory notification |
| * information about the detected condition: |
| * <ul> |
| * <li>The name of the memory pool.</li> |
| * <li>The memory usage of the memory pool when the notification |
| * was constructed.</li> |
| * <li>The number of times that the memory usage has crossed |
| * a threshold when the notification was constructed. |
| * For usage threshold notifications, this count will be the |
| * {@link MemoryPoolMXBean#getUsageThresholdCount usage threshold |
| * count}. For collection threshold notifications, |
| * this count will be the |
| * {@link MemoryPoolMXBean#getCollectionUsageThresholdCount |
| * collection usage threshold count}. |
| * </li> |
| * </ul> |
| * |
| * <p> |
| * A {@link CompositeData CompositeData} representing |
| * the {@code MemoryNotificationInfo} object |
| * is stored in the |
| * {@link javax.management.Notification#setUserData user data} |
| * of a {@link javax.management.Notification notification}. |
| * The {@link #from from} method is provided to convert from |
| * a {@code CompositeData} to a {@code MemoryNotificationInfo} |
| * object. For example: |
| * |
| * <blockquote><pre> |
| * Notification notif; |
| * |
| * // receive the notification emitted by MemoryMXBean and set to notif |
| * ... |
| * |
| * String notifType = notif.getType(); |
| * if (notifType.equals(MemoryNotificationInfo.MEMORY_THRESHOLD_EXCEEDED) || |
| * notifType.equals(MemoryNotificationInfo.MEMORY_COLLECTION_THRESHOLD_EXCEEDED)) { |
| * // retrieve the memory notification information |
| * CompositeData cd = (CompositeData) notif.getUserData(); |
| * MemoryNotificationInfo info = MemoryNotificationInfo.from(cd); |
| * .... |
| * } |
| * </pre></blockquote> |
| * |
| * <p> |
| * The types of notifications emitted by {@code MemoryMXBean} are: |
| * <ul> |
| * <li>A {@link #MEMORY_THRESHOLD_EXCEEDED |
| * usage threshold exceeded notification}. |
| * <br>This notification will be emitted when |
| * the memory usage of a memory pool is increased and has reached |
| * or exceeded its |
| * <a href="MemoryPoolMXBean.html#UsageThreshold"> usage threshold</a> value. |
| * Subsequent crossing of the usage threshold value does not cause |
| * further notification until the memory usage has returned |
| * to become less than the usage threshold value. |
| * </li> |
| * <li>A {@link #MEMORY_COLLECTION_THRESHOLD_EXCEEDED |
| * collection usage threshold exceeded notification}. |
| * <br>This notification will be emitted when |
| * the memory usage of a memory pool is greater than or equal to its |
| * <a href="MemoryPoolMXBean.html#CollectionThreshold"> |
| * collection usage threshold</a> after the Java virtual machine |
| * has expended effort in recycling unused objects in that |
| * memory pool.</li> |
| * </ul> |
| * |
| * @author Mandy Chung |
| * @since 1.5 |
| * |
| */ |
| public class MemoryNotificationInfo { |
| private final String poolName; |
| private final MemoryUsage usage; |
| private final long count; |
| |
| /** |
| * Notification type denoting that |
| * the memory usage of a memory pool has |
| * reached or exceeded its |
| * <a href="MemoryPoolMXBean.html#UsageThreshold"> usage threshold</a> value. |
| * This notification is emitted by {@link MemoryMXBean}. |
| * Subsequent crossing of the usage threshold value does not cause |
| * further notification until the memory usage has returned |
| * to become less than the usage threshold value. |
| * The value of this notification type is |
| * {@code java.management.memory.threshold.exceeded}. |
| */ |
| public static final String MEMORY_THRESHOLD_EXCEEDED = |
| "java.management.memory.threshold.exceeded"; |
| |
| /** |
| * Notification type denoting that |
| * the memory usage of a memory pool is greater than or equal to its |
| * <a href="MemoryPoolMXBean.html#CollectionThreshold"> |
| * collection usage threshold</a> after the Java virtual machine |
| * has expended effort in recycling unused objects in that |
| * memory pool. |
| * This notification is emitted by {@link MemoryMXBean}. |
| * The value of this notification type is |
| * {@code java.management.memory.collection.threshold.exceeded}. |
| */ |
| public static final String MEMORY_COLLECTION_THRESHOLD_EXCEEDED = |
| "java.management.memory.collection.threshold.exceeded"; |
| |
| /** |
| * Constructs a {@code MemoryNotificationInfo} object. |
| * |
| * @param poolName The name of the memory pool which triggers this notification. |
| * @param usage Memory usage of the memory pool. |
| * @param count The threshold crossing count. |
| */ |
| public MemoryNotificationInfo(String poolName, |
| MemoryUsage usage, |
| long count) { |
| if (poolName == null) { |
| throw new NullPointerException("Null poolName"); |
| } |
| if (usage == null) { |
| throw new NullPointerException("Null usage"); |
| } |
| |
| this.poolName = poolName; |
| this.usage = usage; |
| this.count = count; |
| } |
| |
| MemoryNotificationInfo(CompositeData cd) { |
| MemoryNotifInfoCompositeData.validateCompositeData(cd); |
| |
| this.poolName = MemoryNotifInfoCompositeData.getPoolName(cd); |
| this.usage = MemoryNotifInfoCompositeData.getUsage(cd); |
| this.count = MemoryNotifInfoCompositeData.getCount(cd); |
| } |
| |
| /** |
| * Returns the name of the memory pool that triggers this notification. |
| * The memory pool usage has crossed a threshold. |
| * |
| * @return the name of the memory pool that triggers this notification. |
| */ |
| public String getPoolName() { |
| return poolName; |
| } |
| |
| /** |
| * Returns the memory usage of the memory pool |
| * when this notification was constructed. |
| * |
| * @return the memory usage of the memory pool |
| * when this notification was constructed. |
| */ |
| public MemoryUsage getUsage() { |
| return usage; |
| } |
| |
| /** |
| * Returns the number of times that the memory usage has crossed |
| * a threshold when the notification was constructed. |
| * For usage threshold notifications, this count will be the |
| * {@link MemoryPoolMXBean#getUsageThresholdCount threshold |
| * count}. For collection threshold notifications, |
| * this count will be the |
| * {@link MemoryPoolMXBean#getCollectionUsageThresholdCount |
| * collection usage threshold count}. |
| * |
| * @return the number of times that the memory usage has crossed |
| * a threshold when the notification was constructed. |
| */ |
| public long getCount() { |
| return count; |
| } |
| |
| /** |
| * Returns a {@code MemoryNotificationInfo} object represented by the |
| * given {@code CompositeData}. |
| * The given {@code CompositeData} must contain |
| * the following attributes: |
| * <table class="striped" style="margin-left:2em"> |
| * <caption style="display:none">The attributes and the types the given CompositeData contains</caption> |
| * <thead> |
| * <tr> |
| * <th scope="col">Attribute Name</th> |
| * <th scope="col">Type</th> |
| * </tr> |
| * </thead> |
| * <tbody style="text-align:left"> |
| * <tr> |
| * <th scope="row">poolName</th> |
| * <td>{@code java.lang.String}</td> |
| * </tr> |
| * <tr> |
| * <th scope="row">usage</th> |
| * <td>{@code javax.management.openmbean.CompositeData}</td> |
| * </tr> |
| * <tr> |
| * <th scope="row">count</th> |
| * <td>{@code java.lang.Long}</td> |
| * </tr> |
| * </tbody> |
| * </table> |
| * |
| * @param cd {@code CompositeData} representing a |
| * {@code MemoryNotificationInfo} |
| * |
| * @throws IllegalArgumentException if {@code cd} does not |
| * represent a {@code MemoryNotificationInfo} object. |
| * |
| * @return a {@code MemoryNotificationInfo} object represented |
| * by {@code cd} if {@code cd} is not {@code null}; |
| * {@code null} otherwise. |
| */ |
| public static MemoryNotificationInfo from(CompositeData cd) { |
| if (cd == null) { |
| return null; |
| } |
| |
| if (cd instanceof MemoryNotifInfoCompositeData) { |
| return ((MemoryNotifInfoCompositeData) cd).getMemoryNotifInfo(); |
| } else { |
| return new MemoryNotificationInfo(cd); |
| } |
| } |
| } |