code: public void addElement(int value)
    {
  
      if (!m_mutable)
        throw new RuntimeException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_NODESETDTM_NOT_MUTABLE, null)); //"This NodeSetDTM is not mutable!");
  
      super.addElement(value);
    }
docs: Append a Node onto the vector.
  
  @param value The node to be added.
  @throws RuntimeException thrown if this NodeSetDTM is not of
  a mutable type.