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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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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.
/** * 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<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans(); poolNames = new String[pools.size()]; int i = 0; for (MemoryPoolMXBean m : pools) { poolNames[i++] = m.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 }; @Override public MBeanNotificationInfo[] getNotificationInfo() { return new MBeanNotificationInfo[]{ new MBeanNotificationInfo(gcNotifTypes, notifName, "GC Notification") }; } 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); }