code: public static LinkedHashMap<String, RNASequence> readFastaRNASequence(File file, boolean lazySequenceLoad) throws IOException {
  		if (!lazySequenceLoad) {
  			return readFastaRNASequence(file);
  		}
  
  		FastaReader<RNASequence, NucleotideCompound> fastaProxyReader =
  				new FastaReader<RNASequence, NucleotideCompound>(
  						file,
  						new GenericFastaHeaderParser<RNASequence, NucleotideCompound>(),
  						new FileProxyRNASequenceCreator(
  								file,
  								RNACompoundSet.getRNACompoundSet(),
  								new FastaSequenceParser()
  							)
  					);
  		return fastaProxyReader.process();
  
  	}
docs: Selecting lazySequenceLoad=true will parse the FASTA file and figure out the accessionid and offsets and return sequence objects
  that can in the future read the sequence from the disk. This allows the loading of large fasta files where you are only interested
  in one sequence based on accession id.
  @param file
  @param lazySequenceLoad
  @return
  @throws IOException