@Override
public void startBlockEncoding(HFileBlockEncodingContext blkEncodingCtx, DataOutputStream out)
throws IOException {
if (blkEncodingCtx.getClass() != HFileBlockDefaultEncodingContext.class) {
throw new IOException(
this.getClass().getName()
+ " only accepts "
+ HFileBlockDefaultEncodingContext.class.getName()
+ " as the "
+ "encoding context.");
}
HFileBlockDefaultEncodingContext encodingCtx =
(HFileBlockDefaultEncodingContext) blkEncodingCtx;
encodingCtx.prepareEncoding(out);
if (encodingCtx.getHFileContext().isIncludesTags()
&& encodingCtx.getHFileContext().isCompressTags()) {
if (encodingCtx.getTagCompressionContext() != null) {
// It will be overhead to create the TagCompressionContext again and again for every block
// encoding.
encodingCtx.getTagCompressionContext().clear();
} else {
try {
TagCompressionContext tagCompressionContext =
new TagCompressionContext(LRUDictionary.class, Byte.MAX_VALUE);
encodingCtx.setTagCompressionContext(tagCompressionContext);
} catch (Exception e) {
throw new IOException("Failed to initialize TagCompressionContext", e);
}
}
}
StreamUtils.writeInt(out, 0); // DUMMY length. This will be updated in endBlockEncoding()
blkEncodingCtx.setEncodingState(new BufferedDataBlockEncodingState());
}
@Override
public int encode(Cell cell, HFileBlockEncodingContext encodingCtx, DataOutputStream out)
throws IOException {
BufferedDataBlockEncodingState state =
(BufferedDataBlockEncodingState) encodingCtx.getEncodingState();
int encodedKvSize = internalEncode(cell, (HFileBlockDefaultEncodingContext) encodingCtx, out);
state.unencodedDataSizeWritten += encodedKvSize;
return encodedKvSize;
}
@Override
public void endBlockEncoding(
HFileBlockEncodingContext encodingCtx,
DataOutputStream out,
byte[] uncompressedBytesWithHeader)
throws IOException {
BufferedDataBlockEncodingState state =
(BufferedDataBlockEncodingState) encodingCtx.getEncodingState();
// Write the unencodedDataSizeWritten (with header size)
Bytes.putInt(
uncompressedBytesWithHeader,
HConstants.HFILEBLOCK_HEADER_SIZE + DataBlockEncoding.ID_SIZE,
state.unencodedDataSizeWritten);
if (encodingCtx.getDataBlockEncoding() != DataBlockEncoding.NONE) {
encodingCtx.postEncoding(BlockType.ENCODED_DATA);
} else {
encodingCtx.postEncoding(BlockType.DATA);
}
}
/**
* Do the encoding, but do not cache the encoded data.
*
* @return encoded data block with header and checksum
*/
public byte[] encodeData() {
try {
this.dataBlockEncoder.encodeKeyValues(getUncompressedBuffer(), encodingCtx);
} catch (IOException e) {
throw new RuntimeException(
String.format(
"Bug in encoding part of algorithm %s. "
+ "Probably it requested more bytes than are available.",
toString()),
e);
}
return encodingCtx.getUncompressedBytesWithHeader();
}