code: public ParameterBuilder addAll(Map<String, Object> parameters) {
          if (parameters != null) {
              for (String k : parameters.keySet()) {
                  if (parameters.get(k) != null) {
                      this.parameters.put(k, parameters.get(k));
                  }
              }
          }
          return this;
      }
docs: Adds all parameter from a map
  
  @param parameters map with parameters to add. Null values will be skipped.
  @return itself