code: @Override
      public void stateChanged(final CssProperty stateChangedObject) {
  
          if (stateChangedObject instanceof BorderTopWidth) {
              final BorderTopWidth borderTopWidth = (BorderTopWidth) stateChangedObject;
              if (BorderTopWidth.INITIAL.equals(borderTopWidth.getCssValue())
                      || BorderTopWidth.INHERIT
                              .equals(borderTopWidth.getCssValue())) {
                  throw new InvalidValueException(
                          "borderTopWidth cannot have initial/inherit as its cssValue");
              }
          } else if (stateChangedObject instanceof BorderRightWidth) {
              final BorderRightWidth borderRightWidth = (BorderRightWidth) stateChangedObject;
              if (BorderRightWidth.INITIAL.equals(borderRightWidth.getCssValue())
                      || BorderRightWidth.INHERIT
                              .equals(borderRightWidth.getCssValue())) {
                  throw new InvalidValueException(
                          "borderRightWidth cannot have initial/inherit as its cssValue");
              }
          } else if (stateChangedObject instanceof BorderBottomWidth) {
              final BorderBottomWidth borderBottomWidth = (BorderBottomWidth) stateChangedObject;
              if (BorderBottomWidth.INITIAL
                      .equals(borderBottomWidth.getCssValue())
                      || BorderBottomWidth.INHERIT
                              .equals(borderBottomWidth.getCssValue())) {
                  throw new InvalidValueException(
                          "borderBottomWidth cannot have initial/inherit as its cssValue");
              }
          } else if (stateChangedObject instanceof BorderLeftWidth) {
              final BorderLeftWidth borderLeftWidth = (BorderLeftWidth) stateChangedObject;
              if (BorderLeftWidth.INITIAL.equals(borderLeftWidth.getCssValue())
                      || BorderLeftWidth.INHERIT
                              .equals(borderLeftWidth.getCssValue())) {
                  throw new InvalidValueException(
                          "borderLeftWidth cannot have initial/inherit as its cssValue");
              }
          }
  
          assignProducedCssValue(borderTopWidth, borderRightWidth,
                  borderBottomWidth, borderLeftWidth);
  
      }
docs: /*
  (non-Javadoc)
  
  @see
  com.webfirmframework.wffweb.informer.StateChangeInformer#stateChanged(
  java.lang .Object)