code: public void addFilter(Filter filter, Object value) {
          if (filter.getParameterClass().isInstance(value)) {
             parameters.put(filter.repr(), value);
          } else {
              String msg = "You need to supply the correct parameter for the " +
                      filter + " filter. Expecting a(n) " + filter.getParameterClass().getSimpleName();
              throw new FilterParameterException(msg);
          }
      }
docs: Adds a parameter to the search operation
  
  @param filter the filter to be added
  @param value value of the filter to be added. String.valueOf() of this Object is used for the search.