code: public void setHandler(Object handler){
          if(handler instanceof ContentHandler)
              setContentHandler((ContentHandler)handler);
          if(handler instanceof EntityResolver)
              setEntityResolver((EntityResolver)handler);
          if(handler instanceof ErrorHandler)
              setErrorHandler((ErrorHandler)handler);
          if(handler instanceof DTDHandler)
              setDTDHandler((DTDHandler)handler);
          if(handler instanceof LexicalHandler)
              setLexicalHandler((LexicalHandler)handler);
          if(handler instanceof DeclHandler)
              setDeclHandler((DeclHandler)handler);
      }
docs: Registers given handler with all its implementing interfaces.
  This would be handy if you want to register to all interfaces
  implemented by given handler object
  
  @param handler Object implementing one or more sax handler interfaces