Code example for SortedMap

	private DBRevisionInfo retrieveCorrespondingRevision(final String identifier) {
		try { 
			final SortedMap<Long, DBRevisionInfo> retrieved = revisionRetriever
					.retrieveWithIdentifier(identifier);
 
			if (retrieved.isEmpty()) {
				return null; 
			} 
 
			return retrieved.get(retrieved.firstKey());
		} catch (SQLException e) {
			return null; 
		} 
	} 
 
	@Override 
	public boolean satisfy(DBCloneGenealogyInfo genealogy) {
		final long targetStartRevisionId = genealogy.getStartRevisionId();
		final long targetEndRevisionId = genealogy.getEndRevisionId();