public interface BufferPoolMXBean extends PlatformManagedObject
The management interface for a buffer pool, for example a pool of direct
or mapped
buffers.
A class implementing this interface is an MXBean
. A Java virtual machine has one or more implementations of this interface. The getPlatformMXBeans
method can be used to obtain the list of 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 MBeanServer
. The ObjectName
that uniquely identifies the management interface within the MBeanServer
takes the form:
java.nio:type=BufferPool,name=pool namewhere pool name is the
name
of the buffer pool.String getName()
Returns the name representing this buffer pool.
long getCount()
Returns an estimate of the number of buffers in the pool.
long getTotalCapacity()
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.
long getMemoryUsed()
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 capacity
of the buffers in this pool. This difference is explained by alignment, memory allocator, and other implementation specific reasons.
-1L
if an estimate of the memory usage is not available
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