text: public long seek(long ord) {long idx = ord / indexInterval;assert idx < fieldIndex.numIndexTerms;final long offset = fieldIndex.termOffsets.get(idx);final int length = (int) (fieldIndex.termOffsets.get(1+idx) - offset);termBytesReader.fillSlice(term, fieldIndex.termBytesStart + offset, length);this.ord = idx * indexInterval;return fieldIndex.termsStart + fieldIndex.termsDictOffsets.get(idx);}