com.yahoo.memory

Class MapHandle

java.lang.Object

com.yahoo.memory.MapHandle

All Implemented Interfaces:

Handle, AutoCloseable

Direct Known Subclasses:

WritableMapHandle

public class MapHandle
extends Object
implements Handle

Gets a Memory for a memory-mapped, read-only file resource, It is highly recommended that this be created inside a try-with-resources statement.

Author:

Roman Leventov, Lee Rhodes

Method Summary

Modifier and Type	Method and Description
void	close()
Memory	get() Gets a Memory
boolean	isLoaded() Tells whether or not the content is resident in physical memory.
void	load() Loads content into physical memory.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

get

public Memory get()

Description copied from interface: Handle

Gets a Memory

Specified by:

get in interface Handle

Returns:

a Memory

close

public void close()

Specified by:

close in interface Handle

Specified by:

close in interface AutoCloseable

load

public void load()

Loads content into physical memory. This method makes a best effort to ensure that, when it returns, this buffer's content is resident in physical memory. Invoking this method may cause some number of page faults and I/O operations to occur.

See Also:

java/nio/MappedByteBuffer.load

isLoaded

public boolean isLoaded()

Tells whether or not the content is resident in physical memory. A return value of true implies that it is highly likely that all of the data in this buffer is resident in physical memory and may therefore be accessed without incurring any virtual-memory page faults or I/O operations. A return value of false does not necessarily imply that the content is not resident in physical memory. The returned value is a hint, rather than a guarantee, because the underlying operating system may have paged out some of the buffer's data by the time that an invocation of this method returns.

Returns:

true if loaded

See Also:

java /nio/MappedByteBuffer.isLoaded