code: protected boolean checkNextIndexOffset() {
  		if (this.currentSortIndexOffset > this.lastIndexEntryOffset) {
  			MemorySegment returnSegment = nextMemorySegment();
  			if (returnSegment != null) {
  				this.currentSortIndexSegment = returnSegment;
  				this.sortIndex.add(this.currentSortIndexSegment);
  				this.currentSortIndexOffset = 0;
  			} else {
  				return false;
  			}
  		}
  		return true;
  	}
docs: check if we need request next index memory.