code: function(xy, request, url) {
  
          var doc = request.responseXML;
          if(!doc || !doc.documentElement) {
              doc = request.responseText;
          }
          var features = this.format.read(doc);
          if (this.drillDown === false) {
              this.triggerGetFeatureInfo(request, xy, features);
          } else {
              this._requestCount++;
              if (this.output === "object") {
                  this._features = (this._features || []).concat(
                      {url: url, features: features}
                  );
              } else {
              this._features = (this._features || []).concat(features);
              }
              if (this._requestCount === this._numRequests) {
                  this.triggerGetFeatureInfo(request, xy, this._features.concat());
                  delete this._features;
                  delete this._requestCount;
                  delete this._numRequests;
              }
          }
      }
docs: Method: handleResponse
  Handler for the GetFeatureInfo response.
  
  Parameters:
  xy - {<OpenLayers.Pixel>} The position on the map where the
  mouse event occurred.
  request - {XMLHttpRequest} The request object.
  url - {String} The url which was used for this request.