code: public URIBuilder addParameter(final String param, final String value) {
          if (this.queryParams == null) {
              this.queryParams = new ArrayList<NameValuePair>();
          }
          this.queryParams.add(new BasicNameValuePair(param, value));
          this.encodedQuery = null;
          this.encodedSchemeSpecificPart = null;
          return this;
      }
docs: Adds parameter to URI query. The parameter name and value are expected to be unescaped
  and may contain non ASCII characters.