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	/*
	* Copyright (c) 2011, 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 com.sun.management;

	import javax.management.Notification;
	import javax.management.openmbean.CompositeData;
	import javax.management.openmbean.CompositeDataView;
	import javax.management.openmbean.CompositeType;
	import java.util.Collection;
	import java.util.Collections;
	import sun.management.GarbageCollectionNotifInfoCompositeData;

	/**
	* The information about a garbage collection
	*
	* <p>
	* A garbage collection notification is emitted by {@link GarbageCollectorMXBean}
	* when the Java virtual machine completes a garbage collection action
	* The notification emitted will contain the garbage collection notification
	* information about the status of the memory:
	* <u1>
	* <li>The name of the garbage collector used perform the collection.</li>
	* <li>The action performed by the garbage collector.</li>
	* <li>The cause of the garbage collection action.</li>
	* <li>A {@link GcInfo} object containing some statistics about the GC cycle
	(start time, end time) and the memory usage before and after
	the GC cycle.</li>
	* </u1>
	*
	* <p>
	* A {@link CompositeData CompositeData} representing
	* the {@code GarbageCollectionNotificationInfo} object
	* is stored in the
	* {@linkplain javax.management.Notification#setUserData userdata}
	* of a {@linkplain javax.management.Notification notification}.
	* The {@link #from from} method is provided to convert from
	* a {@code CompositeData} to a {@code GarbageCollectionNotificationInfo}
	* object. For example:
	*
	* <blockquote><pre>
	* Notification notif;
	*
	* // receive the notification emitted by a GarbageCollectorMXBean and set to notif
	* ...
	*
	* String notifType = notif.getType();
	* if (notifType.equals(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION)) {
	* // retrieve the garbage collection notification information
	* CompositeData cd = (CompositeData) notif.getUserData();
	* GarbageCollectionNotificationInfo info = GarbageCollectionNotificationInfo.from(cd);
	* ....
	* }
	* </pre></blockquote>
	*
	* <p>
	* The type of the notification emitted by a {@code GarbageCollectorMXBean} is:
	* <ul>
	* <li>A {@linkplain #GARBAGE_COLLECTION_NOTIFICATION garbage collection notification}.
	* <br>Used by every notification emitted by the garbage collector, the details about
	* the notification are provided in the {@linkplain #getGcAction action} String
	* <p></li>
	* </ul>
	**/

	@jdk.Exported
	public class GarbageCollectionNotificationInfo implements CompositeDataView {

	private final String gcName;
	private final String gcAction;
	private final String gcCause;
	private final GcInfo gcInfo;
	private final CompositeData cdata;

	/**
	* Notification type denoting that
	* the Java virtual machine has completed a garbage collection cycle.
	* This notification is emitted by a {@link GarbageCollectorMXBean}.
	* The value of this notification type is
	* {@code com.sun.management.gc.notification}.
	*/
	public static final String GARBAGE_COLLECTION_NOTIFICATION =
	"com.sun.management.gc.notification";

	/**
	* Constructs a {@code GarbageCollectionNotificationInfo} object.
	*
	* @param gcName The name of the garbage collector used to perform the collection
	* @param gcAction The name of the action performed by the garbage collector
	* @param gcCause The cause the garbage collection action
	* @param gcInfo a GcInfo object providing statistics about the GC cycle
	*/
	public GarbageCollectionNotificationInfo(String gcName,
	String gcAction,
	String gcCause,
	GcInfo gcInfo) {
	if (gcName == null) {
	throw new NullPointerException("Null gcName");
	}
	if (gcAction == null) {
	throw new NullPointerException("Null gcAction");
	}
	if (gcCause == null) {
	throw new NullPointerException("Null gcCause");
	}
	this.gcName = gcName;
	this.gcAction = gcAction;
	this.gcCause = gcCause;
	this.gcInfo = gcInfo;
	this.cdata = new GarbageCollectionNotifInfoCompositeData(this);
	}

	GarbageCollectionNotificationInfo(CompositeData cd) {
	GarbageCollectionNotifInfoCompositeData.validateCompositeData(cd);

	this.gcName = GarbageCollectionNotifInfoCompositeData.getGcName(cd);
	this.gcAction = GarbageCollectionNotifInfoCompositeData.getGcAction(cd);
	this.gcCause = GarbageCollectionNotifInfoCompositeData.getGcCause(cd);
	this.gcInfo = GarbageCollectionNotifInfoCompositeData.getGcInfo(cd);
	this.cdata = cd;
	}

	/**
	* Returns the name of the garbage collector used to perform the collection
	*
	* @return the name of the garbage collector used to perform the collection
	*/
	public String getGcName() {
	return gcName;
	}

	/**
	* Returns the action of the performed by the garbage collector
	*
	* @return the the action of the performed by the garbage collector
	*/
	public String getGcAction() {
	return gcAction;
	}

	/**
	* Returns the cause the garbage collection
	*
	* @return the the cause the garbage collection
	*/
	public String getGcCause() {
	return gcCause;
	}

	/**
	* Returns the GC information related to the last garbage collection
	*
	* @return the GC information related to the
	* last garbage collection
	*/
	public GcInfo getGcInfo() {
	return gcInfo;
	}

	/**
	* Returns a {@code GarbageCollectionNotificationInfo} object represented by the
	* given {@code CompositeData}.
	* The given {@code CompositeData} must contain
	* the following attributes:
	* <blockquote>
	* <table border>
	* <tr>
	* <th align=left>Attribute Name</th>
	* <th align=left>Type</th>
	* </tr>
	* <tr>
	* <td>gcName</td>
	* <td>{@code java.lang.String}</td>
	* </tr>
	* <tr>
	* <td>gcAction</td>
	* <td>{@code java.lang.String}</td>
	* </tr>
	* <tr>
	* <td>gcCause</td>
	* <td>{@code java.lang.String}</td>
	* </tr>
	* <tr>
	* <td>gcInfo</td>
	* <td>{@code javax.management.openmbean.CompositeData}</td>
	* </tr>
	* </table>
	* </blockquote>
	*
	* @param cd {@code CompositeData} representing a
	* {@code GarbageCollectionNotificationInfo}
	*
	* @throws IllegalArgumentException if {@code cd} does not
	* represent a {@code GarbaageCollectionNotificationInfo} object.
	*
	* @return a {@code GarbageCollectionNotificationInfo} object represented
	* by {@code cd} if {@code cd} is not {@code null};
	* {@code null} otherwise.
	*/
	public static GarbageCollectionNotificationInfo from(CompositeData cd) {
	if (cd == null) {
	return null;
	}

	if (cd instanceof GarbageCollectionNotifInfoCompositeData) {
	return ((GarbageCollectionNotifInfoCompositeData) cd).getGarbageCollectionNotifInfo();
	} else {
	return new GarbageCollectionNotificationInfo(cd);
	}
	}

	public CompositeData toCompositeData(CompositeType ct) {
	return cdata;
	}

	}

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