code: public static Filter<URI> adaptFilterString2URI(final Filter<String> original) {
  		return new AbstractFilter<URI>() {
  			@Override
  			public boolean apply(final URI uri) {
  				return original.apply(uri.toString());
  			}
  			@Override
  			public String toString() {
  				return original.toString();
  			}
  			@Override
  			public Filter<URI> copy() {
  				return adaptFilterString2URI(original.copy());
  			}
  		};
  	}
docs: Adapts a filter with {@link String} base type to a filter with {@link URI} base type. For testing purposes only.
  
  @param original the original filter.
  @return the adapted filter.