code: public void registerParser(Class<? extends SolrDataQuery> clazz, QueryParser parser) {
  		Assert.notNull(parser, "Cannot register 'null' parser.");
  		parserPairs.add(0, new QueryParserPair(clazz, parser));
  		cache.clear();
  	}
docs: Register additional {@link QueryParser} for {@link SolrQuery}
  
  @param clazz
  @param parser