code: public void setDefaultProperties(Properties defaultProperties) {
  		this.defaultProperties = new HashMap<>();
  		for (Object key : Collections.list(defaultProperties.propertyNames())) {
  			this.defaultProperties.put((String) key, defaultProperties.get(key));
  		}
  	}
docs: Convenient alternative to {@link #setDefaultProperties(Map)}.
  @param defaultProperties some {@link Properties}