code: public void applyDefaults() {
  		if (fillColor == null) {
  			fillColor = "#ffffff"; // white
  		}
  		if (strokeColor == null) {
  			strokeColor = "#000000"; // black
  		}
  		if (strokeOpacity == -1) {
  			strokeOpacity = 1; // fully opaque by default
  		}
  		if (fillOpacity == -1) {
  			fillOpacity = .5f; // 50% transparent by default
  		}
  		if (strokeWidth == -1) {
  			strokeWidth = 1; // white
  		}
  		if (symbol == null) { // circle with radius 10 by default
  			symbol = new SymbolInfo();
  		}
  		if (symbol.getCircle() == null && symbol.getRect() == null && symbol.getImage() == null) {
  			symbol.setCircle(new CircleInfo());
  			symbol.getCircle().setR(10);
  		}
  	}
docs: Applies default values to all properties that have not been set.
  
  @since 1.8.0