Map<String, SearchParseElement> elementParsers = new HashMap<>();
elementParsers.putAll(dfsPhase.parseElements());
elementParsers.putAll(queryPhase.parseElements());
elementParsers.putAll(fetchPhase.parseElements());
elementParsers.put("stats", new StatsGroupsParseElement());
this.elementParsers = ImmutableMap.copyOf(elementParsers);
this.keepAliveReaper = threadPool.scheduleWithFixedDelay(new Reaper(), keepAliveInterval);
this.indicesWarmer.addListener(new NormsWarmer());