diff -r e01e390f6551 -r 645d4b930f93 jdk/src/share/classes/java/nio/BufferPoolMXBean.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/share/classes/java/nio/BufferPoolMXBean.java Tue Aug 26 10:21:22 2008 +0100 @@ -0,0 +1,94 @@ +/* + * Copyright 2007-2008 Sun Microsystems, Inc. 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. Sun designates this + * particular file as subject to the "Classpath" exception as provided + * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + */ + +package java.nio; + +import java.lang.management.PlatformManagedObject; + +/** + * The management interface for a buffer pool. + * + *

A class implementing this interface is an MXBean. A Java + * virtual machine has one or more implementations of this interface. The {@link + * java.lang.management.ManagementFactory#getPlatformMXBeans getPlatformMXBeans} + * method can be used to obtain the list of {@code BufferPoolMXBean} objects + * representing the management interfaces for pools of buffers as follows: + * 

+ *     List<BufferPoolMXBean> pools = ManagementFactory.getPlatformMXBeans(BufferPoolMXBean.class);
+ *
+ * + *

The management interfaces are also registered with the platform {@link + * javax.management.MBeanServer MBeanServer}. The {@link + * javax.management.ObjectName ObjectName} that uniquely identifies the + * management interface within the {@code MBeanServer} takes the form: + *

+ * java.nio:type=BufferPool,name=pool name + *
+ * where pool name is the {@link #getName name} of the buffer pool. + * + * @since 1.7 + */ + +public interface BufferPoolMXBean extends PlatformManagedObject { + + /** + * Returns the name representing this buffer pool. + * + * @return The name of this buffer pool. + */ + String getName(); + + /** + * Returns an estimate of the number of buffers in the pool. + * + * @return An estimate of the number of buffers in this pool + */ + long getCount(); + + /** + * Returns an estimate of the total capacity of the buffers in this pool. + * A buffer's capacity is the number of elements it contains and the value + * returned by this method is an estimate of the total capacity of buffers + * in the pool in bytes. + * + * @return An estimate of the total capacity of the buffers in this pool + * in bytes + */ + long getTotalCapacity(); + + /** + * Returns an estimate of the memory that the Java virtual machine is using + * for this buffer pool. The value returned by this method may differ + * from the estimate of the total {@link #getTotalCapacity capacity} of + * the buffers in this pool. This difference is explained by alignment, + * memory allocator, and other implementation specific reasons. + * + * @return An estimate of the memory that the Java virtual machine is using + * for this buffer pool in bytes, or {@code -1L} if an estimate of + * the memory usage is not available + */ + long getMemoryUsed(); +}