code: protected final void addBundleToMap(String bundleId, String mapping) throws DuplicateBundlePathException {
  
  		for (JoinableResourceBundle bundle : currentBundles) {
  			if (bundleId.equals(bundle.getId()) || this.bundleMapping.containsKey(bundleId)) {
  				Marker fatal = MarkerFactory.getMarker("FATAL");
  				LOGGER.error(fatal, "Duplicate bundle id resulted from mapping:" + bundleId);
  				throw new DuplicateBundlePathException(bundleId);
  			}
  		}
  
  		bundleMapping.put(bundleId, mapping);
  	}
docs: Add a bundle and its mapping to the resulting Map.
  
  @param bundleId
  the bundle Id
  @param mapping
  the mapping
  @throws DuplicateBundlePathException
  if we try to add a bundle with a name, which already exists.