ByteBuf[] byteBufs = writableBatch.getBuffers();
int bytes = 0;
for (int i = 0; i < byteBufs.length; i++) {
bytes += byteBufs[i].writerIndex();
}
DrillBuf byteBuf = allocator.buffer(bytes);
int index = 0;
for (int i = 0; i < byteBufs.length; i++) {
byteBufs[i].readBytes(byteBuf, index, byteBufs[i].writerIndex());
index += byteBufs[i].writerIndex();
}