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GarbageCollectorMXBean.javaAPI DocJava SE 5 API2702Fri Aug 26 14:57:06 BST 2005java.lang.management

GarbageCollectorMXBean

public interface GarbageCollectorMXBean implements 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 {@link MemoryManagerMXBean 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 {@link ManagementFactory#getGarbageCollectorMXBeans} method or from the {@link ManagementFactory#getPlatformMBeanServer platform MBeanServer} method.

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

{@link ManagementFactory#GARBAGE_COLLECTOR_MXBEAN_DOMAIN_TYPE java.lang:type=GarbageCollector},name=collector's name
A platform usually includes additional platform-dependent information specific to a garbage collection algorithm for monitoring.
see
MemoryMXBean
see
JMX Specification.
see
Ways to Access MXBeans
author
Mandy Chung
version
1.9, 04/20/04
since
1.5

Fields Summary
Constructors Summary
Methods Summary
public longgetCollectionCount()
Returns the total number of collections that have occurred. This method returns -1 if the collection count is undefined for this collector.

return
the total number of collections that have occurred.

public longgetCollectionTime()
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.

return
the approximate accumulated collection elapsed time in milliseconds.