protected final void afterDecodingKeyValue(
DataInputStream source, ByteBuffer dest, HFileBlockDefaultDecodingContext decodingCtx)
throws IOException {
if (decodingCtx.getHFileContext().isIncludesTags()) {
int tagsLength = ByteBufferUtils.readCompressedInt(source);
// Put as unsigned short
dest.put((byte) ((tagsLength >> 8) & 0xff));
dest.put((byte) (tagsLength & 0xff));
if (tagsLength > 0) {
TagCompressionContext tagCompressionContext = decodingCtx.getTagCompressionContext();
// When tag compression is been used in this file, tagCompressionContext will have a not
// null value passed.
if (tagCompressionContext != null) {
tagCompressionContext.uncompressTags(source, dest, tagsLength);
} else {
ByteBufferUtils.copyFromStreamToBuffer(dest, source, tagsLength);
}
}
}
if (decodingCtx.getHFileContext().isIncludesMvcc()) {
long memstoreTS = -1;
try {
// Copy memstore timestamp from the data input stream to the byte
// buffer.
memstoreTS = WritableUtils.readVLong(source);
ByteBufferUtils.writeVLong(dest, memstoreTS);
} catch (IOException ex) {
throw new RuntimeException(
"Unable to copy memstore timestamp " + memstoreTS + " after decoding a key/value");
}
}
}
@Override
public ByteBuffer decodeKeyValues(
DataInputStream source, HFileBlockDecodingContext blkDecodingCtx) throws IOException {
if (blkDecodingCtx.getClass() != HFileBlockDefaultDecodingContext.class) {
throw new IOException(
this.getClass().getName()
+ " only accepts "
+ HFileBlockDefaultDecodingContext.class.getName()
+ " as the decoding context.");
}
HFileBlockDefaultDecodingContext decodingCtx =
(HFileBlockDefaultDecodingContext) blkDecodingCtx;
if (decodingCtx.getHFileContext().isIncludesTags()
&& decodingCtx.getHFileContext().isCompressTags()) {
if (decodingCtx.getTagCompressionContext() != null) {
// It will be overhead to create the TagCompressionContext again and again for every block
// decoding.
decodingCtx.getTagCompressionContext().clear();
} else {
try {
TagCompressionContext tagCompressionContext =
new TagCompressionContext(LRUDictionary.class, Byte.MAX_VALUE);
decodingCtx.setTagCompressionContext(tagCompressionContext);
} catch (Exception e) {
throw new IOException("Failed to initialize TagCompressionContext", e);
}
}
}
return internalDecodeKeyValues(source, 0, 0, decodingCtx);
}
