code: public void setSpacerImage(String spacerImage)
      {
          String val = setNonEmptyValueAttribute(spacerImage);
          if (val != null)
              _iState.setImageSpacer(setNonEmptyValueAttribute(val));
      }
docs: Sets the image name for a spacer image used to align the other images inside the tree.  (Defaults to "spacer.gif").
  @param spacerImage the image name (including extension)
  @jsptagref.attributedescription Sets the image name for a spacer image used to align the other images inside the tree.
  (Defaults to "spacer.gif").
  @jsptagref.databindable false
  @jsptagref.attributesyntaxvalue <i>string_spacerImage</i>
  @netui:attribute required="false"  rtexprvalue="true"
  description="Sets the image name for a spacer image used to align the other images inside the tree."