code: public void addLayoutMapping(String viewName, String layoutName) {
  		log.debug("Add new layout mapping");
  		log.trace("  => {} -> {}", viewName, layoutName);
  
  		notNull(viewName, "View name must not be null");
  		notNull(layoutName, "Layout name must not be null");
  		this.layoutMappings.put(viewName, layoutName);
  	}
docs: Replace current layout mappings by new mappings.
  
  @param viewName View name to map.
  @param layoutName Layout name to use for given view.