}
HFileBlock unpacked = new HFileBlock(this);
unpacked.allocateBuffer(); // allocates space for the decompressed block
HFileBlockDecodingContext ctx = blockType == BlockType.ENCODED_DATA ?
reader.getBlockDecodingContext() : reader.getDefaultBlockDecodingContext();
ByteBuffer dup = this.buf.duplicate();
dup.position(this.headerSize());
dup = dup.slice();
ctx.prepareDecoding(unpacked.getOnDiskSizeWithoutHeader(),
unpacked.getUncompressedSizeWithoutHeader(), unpacked.getBufferWithoutHeader(),
dup);
// Preserve the next block's header bytes in the new block if we have them.
if (unpacked.hasNextBlockHeader()) {