Interface GarbageCollectorMXBean

All Superinterfaces:
MemoryManagerMXBean, PlatformManagedObject

public interface GarbageCollectorMXBean
extends MemoryManagerMXBean

The management interface for the garbage collection of the Java virtual machine. Garbage collection is the process that the Java virtual machine uses to find and reclaim unreachable objects to free up memory space. A garbage collector is one type of memory manager.

A Java virtual machine may have one or more instances of the implementation class of this interface. An instance implementing this interface is an MXBean that can be obtained by calling the ManagementFactory.getGarbageCollectorMXBeans() method or from the platform MBeanServer method.

The ObjectName for uniquely identifying the MXBean for a garbage collector within an MBeanServer is:

java.lang:type=GarbageCollector,name=collector's name
It can be obtained by calling the PlatformManagedObject.getObjectName() method. A platform usually includes additional platform-dependent information specific to a garbage collection algorithm for monitoring.
Since:
1.5
See Also:
ManagementFactory.getPlatformMXBeans(Class), MemoryMXBean, JMX Specification., Ways to Access MXBeans

Methods

Modifier and Type Method and Description
long getCollectionCount()

Returns the total number of collections that have occurred.

long getCollectionTime()

Returns the approximate accumulated collection elapsed time in milliseconds.

Methods inherited from interface java.lang.management.MemoryManagerMXBean

getMemoryPoolNames, getName, isValid

Methods inherited from interface java.lang.management.PlatformManagedObject

getObjectName

Methods

getCollectionCount

long getCollectionCount()

Returns the total number of collections that have occurred. This method returns -1 if the collection count is undefined for this collector.

Returns:
the total number of collections that have occurred.

getCollectionTime

long getCollectionTime()

Returns the approximate accumulated collection elapsed time in milliseconds. This method returns -1 if the collection elapsed time is undefined for this collector.

The Java virtual machine implementation may use a high resolution timer to measure the elapsed time. This method may return the same value even if the collection count has been incremented if the collection elapsed time is very short.

Returns:
the approximate accumulated collection elapsed time in milliseconds.

© 1993, 2020, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
https://docs.oracle.com/javase/8/docs/api/java/lang/management/GarbageCollectorMXBean.html