Class MappedByteBufferInputStream

Method Details

• setSynchronous

  public final void setSynchronous(boolean s)

  Enable or disable synchronous mode.

  If synchronous mode is enabled, mapped buffers will be flushed if resized, written to or closing in read-write mapping mode.

  If synchronous mode is enabled, FileChannel.force(boolean) is issued if resizing or closing and not in read-only mapping mode.

  Parameters:

  s - true to enable synchronous mode

• getSynchronous

  public final boolean getSynchronous()

  Return synchronous mode.

• close

  public final void close() throws IOException

  Specified by:

  close in interface AutoCloseable

  Specified by:

  close in interface Closeable

  Overrides:

  close in class InputStream

  Throws:

  IOException

• setFileResizeOp

  public final void setFileResizeOp(MappedByteBufferInputStream.FileResizeOp fileResizeOp) throws IllegalStateException

  Parameters:

  fileResizeOp - the new MappedByteBufferInputStream.FileResizeOp.

  Throws:

  IllegalStateException - if attempting to set the MappedByteBufferInputStream.FileResizeOp to a different value than before

• setLength

  public final void setLength(long newTotalSize) throws IOException

  Resize the underlying FileChannel's size and adjusting this instance via accordingly.

  User must have a MappedByteBufferInputStream.FileResizeOp registered before.

  Implementation calls notifyLengthChange(long) after MappedByteBufferInputStream.FileResizeOp.setLength(long).

  Parameters:

  newTotalSize - the new total size

  Throws:

  IOException - if no MappedByteBufferInputStream.FileResizeOp has been registered or if a buffer slice operation failed

• notifyLengthChange

  public final void notifyLengthChange(long newTotalSize) throws IOException

  Notify this instance that the underlying FileChannel's size has been changed and adjusting this instances buffer slices and states accordingly.

  Should be called by user API when aware of such event.

  Parameters:

  newTotalSize - the new total size

  Throws:

  IOException - if a buffer slice operation failed

• flush

  public final void flush(boolean metaData) throws IOException

  Similar to OutputStream.flush(), synchronizes all mapped buffers from local storage via MappedByteBuffer.force() as well as the FileChannel.force(boolean) w/o metaData.

  Parameters:

  metaData - TODO

  Throws:

  IOException - if this stream has been closed.

• getOutputStream

  public final MappedByteBufferOutputStream getOutputStream(MappedByteBufferInputStream.FileResizeOp fileResizeOp) throws IllegalStateException, IOException

  Returns a new MappedByteBufferOutputStream instance sharing all resources of this input stream, including all buffer slices.

  Throws:

  IllegalStateException - if attempting to set the MappedByteBufferInputStream.FileResizeOp to a different value than before

  IOException - if this instance was opened w/ FileChannel.MapMode.READ_ONLY or if this stream has been closed.

• currentSlice

  public final ByteBuffer currentSlice() throws IOException

  Return the mapped ByteBuffer slice at the current position().

  Due to the nature of using sliced buffers mapping the whole region, user has to determine whether the returned buffer covers the desired region and may fetch the nextSlice() until satisfied.
  It is also possible to repeat this operation after reposition the stream via position(long) or skip(long) to a position within the next block, similar to nextSlice().

  Throws:

  IOException - if a buffer slice operation failed.

• nextSlice

  public final ByteBuffer nextSlice() throws IOException

  Return the next mapped ByteBuffer slice from the current position(), implicitly setting position(long) to the start of the returned next slice, see currentSlice().

  If no subsequent slice is available, null is being returned.

  Throws:

  IOException - if a buffer slice operation failed.

• getCacheMode

  public final MappedByteBufferInputStream.CacheMode getCacheMode()

  Return the used MappedByteBufferInputStream.CacheMode.

  If a desired MappedByteBufferInputStream.CacheMode is not available, it may fall back to an available one at runtime, see MappedByteBufferInputStream.CacheMode.FLUSH_PRE_HARD.
  This evaluation only happens if the MappedByteBufferInputStream.CacheMode != MappedByteBufferInputStream.CacheMode.FLUSH_NONE and while attempting to flush an unused buffer slice.

• length

  public final long length()

  Returns the total size in bytes of the InputStream

     0 <= position() <= length()
   

• remaining

  public final long remaining() throws IOException

  Returns the number of remaining available bytes of the InputStream, i.e. length() - position().

     0 <= position() <= length()
   

  In contrast to InputStream's available() method, this method returns the proper return type long.

  Throws:

  IOException - if a buffer slice operation failed.

• available

  public final int available() throws IOException

  See remaining() for an accurate variant.

  Overrides:

  available in class InputStream

  Throws:

  IOException - if a buffer slice operation failed.

• position

  public final long position() throws IOException

  Returns the absolute position of the InputStream.

     0 <= position() <= length()
   

  Throws:

  IOException - if a buffer slice operation failed.

• position

  public final MappedByteBufferInputStream position(long newPosition) throws IOException

  Sets the absolute position of the InputStream to newPosition.

     0 <= position() <= length()
   

  Parameters:

  newPosition - The new position, which must be non-negative and ≤ length().

  Returns:

  this instance

  Throws:

  IOException - if a buffer slice operation failed or stream is closed.

• markSupported

  public final boolean markSupported()

  Overrides:

  markSupported in class InputStream

• mark

  public final void mark(int readlimit)

  Parameter readLimit is not used in this implementation, since the whole file is memory mapped and no read limitation occurs.

  Overrides:

  mark in class InputStream

• reset

  public final void reset() throws IOException

  Overrides:

  reset in class InputStream

  Throws:

  IOException - if this stream has not been marked, a buffer slice operation failed or stream has been closed.

• skip

  public final long skip(long n) throws IOException

  Overrides:

  skip in class InputStream

  Throws:

  IOException - if a buffer slice operation failed or stream is closed.

• read

  public final int read() throws IOException

  Specified by:

  read in class InputStream

  Throws:

  IOException

• read

  public final int read(byte[] b, int off, int len) throws IOException

  Overrides:

  read in class InputStream

  Throws:

  IOException

• read

  public final int read(ByteBuffer b, int len) throws IOException

  Perform similar to read(byte[], int, int) with ByteBuffer instead of byte array.

  Parameters:

  b - the ByteBuffer sink, data is written at current Buffer.position()

  len - the number of bytes to read

  Returns:

  the number of bytes read, -1 for EOS

  Throws:

  IOException - if a buffer slice operation failed or stream has been closed.