code: private void init() {
          if (Double.compare(getWidth(), 0) <= 0 || Double.compare(getHeight(), 0) <= 0 ||
              Double.compare(getPrefWidth(), 0) <= 0 || Double.compare(getPrefHeight(), 0) <= 0) {
              setPrefSize(PREFERRED_WIDTH, PREFERRED_HEIGHT);
          }
          if (Double.compare(getMinWidth(), 0) <= 0 || Double.compare(getMinHeight(), 0) <= 0) {
              setMinSize(MINIMUM_WIDTH, MINIMUM_HEIGHT);
          }
          if (Double.compare(getMaxWidth(), 0) <= 0 || Double.compare(getMaxHeight(), 0) <= 0) {
              setMaxSize(MAXIMUM_WIDTH, MAXIMUM_HEIGHT);
          }
      }
docs: ******************** Initialization ************************************