@Override
      public boolean isAcceptable(Object element, PsiElement context) {
        final PsiElement parent = context.getParent();

        if((parent instanceof XmlEntityDecl &&
           !((XmlEntityDecl)parent).isInternalReference()
           )
          ) {
          PsiElement prevSibling = context.getPrevSibling();
          if (prevSibling instanceof PsiWhiteSpace) {
            prevSibling = prevSibling.getPrevSibling();
          }

          if (prevSibling instanceof XmlToken &&
              ((XmlToken)prevSibling).getTokenType() == XmlTokenType.XML_DOCTYPE_SYSTEM ||
              prevSibling instanceof XmlAttributeValue
            ) {
            return true;
          }
        }

        return false;
      }
@Override
      public boolean isAcceptable(Object element, PsiElement context)