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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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package java.lang.management;
/**
* 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}.
*
* <p> A Java virtual machine may have one or more instances of
* the implementation class of this interface.
* An instance implementing this interface is
* an <a href="ManagementFactory.html#MXBean">MXBean</a>
* that can be obtained by calling
* the {@link ManagementFactory#getGarbageCollectorMXBeans} method or
* from the {@link ManagementFactory#getPlatformMBeanServer
* platform <tt>MBeanServer</tt>} method.
*
* <p>The <tt>ObjectName</tt> for uniquely identifying the MXBean for
* a garbage collector within an MBeanServer is:
* <blockquote>
* {@link ManagementFactory#GARBAGE_COLLECTOR_MXBEAN_DOMAIN_TYPE
* <tt>java.lang:type=GarbageCollector</tt>}<tt>,name=</tt><i>collector's name</i>
* </blockquote>
*
* A platform usually includes additional platform-dependent information
* specific to a garbage collection algorithm for monitoring.
*
* @see MemoryMXBean
*
* @see <a href="../../../javax/management/package-summary.html">
* JMX Specification.</a>
* @see <a href="package-summary.html#examples">
* Ways to Access MXBeans</a>
*
* @author Mandy Chung
* @since 1.5
*/
public interface GarbageCollectorMXBean extends MemoryManagerMXBean {
/**
* Returns the total number of collections that have occurred.
* This method returns <tt>-1</tt> if the collection count is undefined for
* this collector.
*
* @return the total number of collections that have occurred.
*/
public long getCollectionCount();
/**
* Returns the approximate accumulated collection elapsed time
* in milliseconds. This method returns <tt>-1</tt> if the collection
* elapsed time is undefined for this collector.
* <p>
* 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.
*/
public long getCollectionTime();
}