Codons get(final int index) {
				Codons result = _codons[index];
				if (result == null) {
					result = Codons.ofIntegerGenes(_genotype.get(index));
					_codons[index] = result;
				}

				return result;
			}
Caching and lazy creation of codons.
jenetics.ext/src/main/java/io/jenetics/ext/grammar/MultiIntegerChromosomeMapper.java