code: protected String getCachedFileName(String key) throws InterruptedException {
  		String result = null;
  		if (_moduleBuilds != null) {
  			CacheEntry bld = _moduleBuilds.get(key);
  			for (int i = 0; i < 5; i++) {
  				if (bld.filename == null) {
  					Thread.sleep(500L);
  				}
  			}
  			result = _moduleBuilds.get(key).fileName();
  		}
  		return result;
  	}
docs: /*
  This accessor is provided for unit testing only