code: public SpringApplicationBuilder properties(Map<String, Object> defaults) {
  		this.defaultProperties.putAll(defaults);
  		this.application.setDefaultProperties(this.defaultProperties);
  		if (this.parent != null) {
  			this.parent.properties(this.defaultProperties);
  			this.parent.environment(this.environment);
  		}
  		return this;
  	}
docs: Default properties for the environment. Multiple calls to this method are
  cumulative.
  @param defaults the default properties
  @return the current builder
  @see SpringApplicationBuilder#properties(String...)