java.nio
Class MappedByteBuffer

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

All Implemented Interfaces:

Comparable<ByteBuffer>

Direct Known Subclasses:

MappedByteBufferAdapter

public abstract class MappedByteBuffer
extends ByteBuffer

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.

Field Summary

(package private) DirectByteBuffer

wrapped

Fields inherited from class java.nio.ByteBuffer

order

Fields inherited from class java.nio.Buffer

_elementSizeShift, capacity, limit, mark, position, UNSET_MARK

Constructor Summary

MappedByteBuffer(ByteBuffer directBuffer)

MappedByteBuffer(org.apache.harmony.luni.platform.PlatformAddress addr, int capa, int offset, int mode)

Method Summary

MappedByteBuffer	force() Writes all changes of the buffer to the mapped file.
boolean	isLoaded() Returns true if this buffer's content is loaded.
MappedByteBuffer	load() Loads this buffer's content into memory.

Methods inherited from class java.nio.ByteBuffer

_array, _arrayOffset, allocate, allocateDirect, array, arrayOffset, asCharBuffer, asDoubleBuffer, asFloatBuffer, asIntBuffer, asLongBuffer, asReadOnlyBuffer, asShortBuffer, compact, compareTo, duplicate, equals, get, get, get, get, getChar, getChar, getDouble, getDouble, getFloat, getFloat, getInt, getInt, getLong, getLong, getShort, getShort, hasArray, hashCode, isDirect, order, order, orderImpl, protectedArray, protectedArrayOffset, protectedHasArray, put, put, put, put, put, putChar, putChar, putDouble, putDouble, putFloat, putFloat, putInt, putInt, putLong, putLong, putShort, putShort, slice, toString, wrap, wrap

Methods inherited from class java.nio.Buffer

capacity, clear, flip, hasRemaining, isReadOnly, limit, limit, mark, position, position, remaining, reset, rewind

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

wrapped

final DirectByteBuffer wrapped

Constructor Detail

MappedByteBuffer

MappedByteBuffer(ByteBuffer directBuffer)

MappedByteBuffer

MappedByteBuffer(org.apache.harmony.luni.platform.PlatformAddress addr,
                 int capa,
                 int offset,
                 int mode)

Method Detail

isLoaded

public final boolean isLoaded()

Returns true if this buffer's content is loaded.

Returns:

True if this buffer's content is loaded.

load

public final MappedByteBuffer load()

Loads this buffer's content into memory.

Returns:

This buffer

force

public final MappedByteBuffer force()

Writes all changes of the buffer to the mapped file. All changes must be written by invoking this method if the mapped file exists on the local device, otherwise the action can not be specified.

Returns:

This buffer