/* * Copyright (c) 2003, 2011, 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 sun.management; import com.sun.management.GarbageCollectorMXBean;import com.sun.management.GarbageCollectionNotificationInfo;import java.lang.management.ManagementFactory;import java.lang.management.MemoryPoolMXBean;import java.lang.management.MemoryUsage; import com.sun.management.GcInfo;import javax.management.openmbean.CompositeData;import javax.management.MBeanInfo;import javax.management.MBeanAttributeInfo;import javax.management.ObjectName;import javax.management.MBeanNotificationInfo;import javax.management.Notification;import javax.management.NotificationFilter;import javax.management.NotificationListener;import javax.management.ListenerNotFoundException; import java.util.List;import java.util.ListIterator;import java.util.Map; /** * Implementation class for the garbage collector. * Standard and committed hotspot-specific metrics if any. * * ManagementFactory.getGarbageCollectorMXBeans() returns a list * of instances of this class. */class GarbageCollectorImpl extends MemoryManagerImpl    implements GarbageCollectorMXBean {     GarbageCollectorImpl(String name) {        super(name);    }     public native long getCollectionCount();    public native long getCollectionTime();      // The memory pools are static and won't be changed.    // TODO: If the hotspot implementation begins to have pools    // dynamically created and removed, this needs to be modified.    private String[] poolNames = null;    synchronized String[] getAllPoolNames() {        if (poolNames == null) {            List pools = ManagementFactory.getMemoryPoolMXBeans();            poolNames = new String[pools.size()];            int i = 0;            for (ListIterator iter = pools.listIterator();                 iter.hasNext();                 i++) {                MemoryPoolMXBean p = (MemoryPoolMXBean) iter.next();                poolNames[i] = p.getName();            }        }        return poolNames;    }     // Sun JDK extension    private GcInfoBuilder gcInfoBuilder;     private synchronized GcInfoBuilder getGcInfoBuilder() {        if(gcInfoBuilder == null) {            gcInfoBuilder = new GcInfoBuilder(this, getAllPoolNames());        }        return gcInfoBuilder;    }     public GcInfo getLastGcInfo() {        GcInfo info = getGcInfoBuilder().getLastGcInfo();        return info;    }     private final static String notifName =        "javax.management.Notification";     private final static String[] gcNotifTypes = {        GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION    };     private MBeanNotificationInfo[] notifInfo = null;    public MBeanNotificationInfo[] getNotificationInfo() {        synchronized (this) {            if (notifInfo == null) {                 notifInfo = new MBeanNotificationInfo[1];                 notifInfo[0] = new MBeanNotificationInfo(gcNotifTypes,                                                          notifName,                                                          "GC Notification");            }        }        return notifInfo;    }     private static long seqNumber = 0;    private static long getNextSeqNumber() {        return ++seqNumber;    }     void createGCNotification(long timestamp,                              String gcName,                              String gcAction,                              String gcCause,                              GcInfo gcInfo)  {         if (!hasListeners()) {            return;        }         Notification notif = new Notification(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION,                                              getObjectName(),                                              getNextSeqNumber(),                                              timestamp,                                              gcName);        GarbageCollectionNotificationInfo info =            new GarbageCollectionNotificationInfo(gcName,                                                  gcAction,                                                  gcCause,                                                  gcInfo);         CompositeData cd =            GarbageCollectionNotifInfoCompositeData.toCompositeData(info);        notif.setUserData(cd);        sendNotification(notif);    }     public synchronized void addNotificationListener(NotificationListener listener,                                                     NotificationFilter filter,                                                     Object handback)    {        boolean before = hasListeners();        super.addNotificationListener(listener, filter, handback);        boolean after = hasListeners();        if (!before && after) {            setNotificationEnabled(this, true);        }    }     public synchronized void removeNotificationListener(NotificationListener listener)        throws ListenerNotFoundException {        boolean before = hasListeners();        super.removeNotificationListener(listener);        boolean after = hasListeners();        if (before && !after) {            setNotificationEnabled(this,false);        }    }     public synchronized void removeNotificationListener(NotificationListener listener,                                                        NotificationFilter filter,                                                        Object handback)            throws ListenerNotFoundException    {        boolean before = hasListeners();        super.removeNotificationListener(listener,filter,handback);        boolean after = hasListeners();        if (before && !after) {            setNotificationEnabled(this,false);        }    }     public ObjectName getObjectName() {        return Util.newObjectName(ManagementFactory.GARBAGE_COLLECTOR_MXBEAN_DOMAIN_TYPE, getName());    }     native void setNotificationEnabled(GarbageCollectorMXBean gc,                                       boolean enabled); }