com.healthmarketscience.jackcess.impl
Interface CodecHandler

All Known Implementing Classes:

DefaultCodecProvider.DummyHandler, DefaultCodecProvider.UnsupportedHandler

public interface CodecHandler

Interface for a handler which can encode/decode a specific access page encoding.

Author:

James Ahlborn

Method Summary

boolean	canDecodeInline() Returns true if this handler can decode a page inline, false otherwise.
boolean	canEncodePartialPage() Returns true if this handler can encode partial pages, false otherwise.
void	decodePage(ByteBuffer inPage, ByteBuffer outPage, int pageNumber) Decodes the given page buffer.
ByteBuffer	encodePage(ByteBuffer page, int pageNumber, int pageOffset) Encodes the given page buffer into a new page buffer and returns it.

Method Detail

canEncodePartialPage

boolean canEncodePartialPage()

Returns true if this handler can encode partial pages, false otherwise. If this method returns false, the encodePage(java.nio.ByteBuffer, int, int) method will never be called with a non-zero pageOffset.

canDecodeInline

boolean canDecodeInline()

Returns true if this handler can decode a page inline, false otherwise. If this method returns false, the decodePage(java.nio.ByteBuffer, java.nio.ByteBuffer, int) method will always be called with separate buffers.

decodePage

void decodePage(ByteBuffer inPage,
                ByteBuffer outPage,
                int pageNumber)
                throws IOException

Decodes the given page buffer.

Parameters:

inPage - the page to be decoded

outPage - the decoded page. if canDecodeInline() is true, this will be the same buffer as inPage.

pageNumber - the page number of the given page

Throws:

IOException - if an exception occurs during decoding

encodePage

ByteBuffer encodePage(ByteBuffer page,
                      int pageNumber,
                      int pageOffset)
                      throws IOException

Encodes the given page buffer into a new page buffer and returns it. The returned page buffer will be used immediately and discarded so that it may be re-used for subsequent page encodings.

Parameters:

page - the page to be encoded, should not be modified

pageNumber - the page number of the given page

pageOffset - offset within the page at which to start writing the page data

Returns:

the properly encoded page buffer for the given page buffer

Throws:

IOException - if an exception occurs during decoding