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Android APIs
public abstract class

MappedByteBuffer

extends ByteBuffer
java.lang.Object
   ↳ java.nio.Buffer
     ↳ java.nio.ByteBuffer
       ↳ java.nio.MappedByteBuffer

Class Overview

MappedByteBuffer is a special kind of direct byte buffer which maps a region of file to memory.

MappedByteBuffer can be created by calling FileChannel.map. Once created, the mapping between the byte buffer and the file region remains valid until the byte buffer is garbage collected.

All or part of a MappedByteBuffer's content may change or become inaccessible at any time, since the mapped file region can be modified by another thread or process at any time. If this happens, the behavior of the MappedByteBuffer is undefined.

Summary

Public Methods
final MappedByteBuffer force()
Flushes changes made to the in-memory buffer back to the mapped file.
final boolean isLoaded()
Returns true if there is a high probability that every page of this buffer is currently loaded in RAM, meaning that accesses will not cause a page fault.
final MappedByteBuffer load()
Attempts to load every page of this buffer into RAM.
[Expand]
Inherited Methods
From class java.nio.ByteBuffer
From class java.nio.Buffer
From class java.lang.Object
From interface java.lang.Comparable

Public Methods

public final MappedByteBuffer force ()

Added in API level 1

Flushes changes made to the in-memory buffer back to the mapped file. Unless you call this, changes may not be written back until the finalizer runs. This method waits for the write to complete before returning.

Returns
  • this buffer.

public final boolean isLoaded ()

Added in API level 1

Returns true if there is a high probability that every page of this buffer is currently loaded in RAM, meaning that accesses will not cause a page fault. It is impossible to give a strong guarantee since this is only a snapshot of a dynamic situation.

public final MappedByteBuffer load ()

Added in API level 1

Attempts to load every page of this buffer into RAM. See isLoaded().

Returns
  • this buffer.