code: protected Object transformRequest(DSRequest request) {
  		String requestId = request.getRequestId();
  		DSResponse response = new DSResponse();
  		response.setAttribute("clientContext", request.getAttributeAsObject("clientContext"));
  
  		response.setStatus(0);
  		switch (request.getOperationType()) {
  			case FETCH:
  				executeFetch(requestId, request, response);
  				break;
  			case ADD:
  				// Operation not implemented.
  				break;
  			case UPDATE:
  				// Operation not implemented.
  				break;
  			case REMOVE:
  				// Operation not implemented.
  				break;
  			default:
  				// Operation not implemented.
  				break;
  		}
  		return request.getData();
  	}
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