code: public String buildRevision(final char[] previousRevision)
  	{
  		String prevRev = null;
  		if (previousRevision != null) {
  			prevRev = String.valueOf(previousRevision);
  		}
  
  		return buildRevision(prevRev);
  	}
docs: Builds the current revision.
  
  @param previousRevision
  content of the previous revision
  @return current revision