A direct byte buffer whose content is a memory-mapped region of a file.
<p> Mapped byte buffers are created via the {@link
java.nio.channels.FileChannel#map FileChannel.map} method. This class
extends the {@link ByteBuffer} class with operations that are specific to
memory-mapped file regions.
<p> A mapped byte buffer and the file mapping that it represents remain
valid until the buffer itself is garbage-collected.
<p> The content of a mapped byte buffer can change at any time, for example
if the content of the corresponding region of the mapped file is changed by
this program or another. Whether or not such changes occur, and when they
occur, is operating-system dependent and therefore unspecified.
<a name="inaccess"></a><p> All or part of a mapped byte buffer may become
inaccessible at any time, for example if the mapped file is truncated. An
attempt to access an inaccessible region of a mapped byte buffer will not
change the buffer's content and will cause an unspecified exception to be
thrown either at the time of the access or at some later time. It is
therefore strongly recommended that appropriate precautions be taken to
avoid the manipulation of a mapped file by this program, or by a
concurrently running program, except to read or write the file's content.
<p> Mapped byte buffers otherwise behave no differently than ordinary direct
byte buffers. </p>
A direct byte buffer whose content is a memory-mapped region of a file.
<p> Mapped byte buffers are created via the {@link java.nio.channels.FileChannel#map FileChannel.map} method. This class extends the {@link ByteBuffer} class with operations that are specific to memory-mapped file regions.
<p> A mapped byte buffer and the file mapping that it represents remain valid until the buffer itself is garbage-collected.
<p> The content of a mapped byte buffer can change at any time, for example if the content of the corresponding region of the mapped file is changed by this program or another. Whether or not such changes occur, and when they occur, is operating-system dependent and therefore unspecified.
<a name="inaccess"></a><p> All or part of a mapped byte buffer may become inaccessible at any time, for example if the mapped file is truncated. An attempt to access an inaccessible region of a mapped byte buffer will not change the buffer's content and will cause an unspecified exception to be thrown either at the time of the access or at some later time. It is therefore strongly recommended that appropriate precautions be taken to avoid the manipulation of a mapped file by this program, or by a concurrently running program, except to read or write the file's content.
<p> Mapped byte buffers otherwise behave no differently than ordinary direct byte buffers. </p>