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package java.lang.management;
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 name
where pool name is the name of the buffer pool. Since: 1.7
/**
* The management interface for a buffer pool, for example a pool of
* {@link java.nio.ByteBuffer#allocateDirect direct} or {@link
* java.nio.MappedByteBuffer mapped} buffers.
*
* <p> A class implementing this interface is an
* {@link javax.management.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:
* <pre>
* List<BufferPoolMXBean> pools = ManagementFactory.getPlatformMXBeans(BufferPoolMXBean.class);
* </pre>
*
* <p> 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:
* <pre>
* java.nio:type=BufferPool,name=<i>pool name</i>
* </pre>
* where <em>pool name</em> is the {@link #getName name} of the buffer pool.
*
* @since 1.7
*/
public interface BufferPoolMXBean extends PlatformManagedObject {
Returns the name representing this buffer pool.
Returns: The name of this buffer pool.
/**
* 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.
Returns: An estimate of the number of buffers in this pool
/**
* 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.
Returns: An estimate of the total capacity of the buffers in this pool
in bytes
/**
* 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 capacity of the buffers in this pool. This difference is explained by alignment, memory allocator, and other implementation specific reasons. Returns: An estimate of the memory that the Java virtual machine is using for this buffer pool in bytes, or -1L if an estimate of the memory usage is not available
/**
* 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();
}