private void registerHeaderOperatorConverters() {
registerHeaderOperatorConverter(
SearchQuery.ExistsOperator.class,
(headerName, operator) ->
existsQuery(JsonMessageConstants.HEADERS + "." + headerName));
registerHeaderOperatorConverter(
SearchQuery.AddressOperator.class,
(headerName, operator) -> manageAddressFields(headerName, operator.getAddress()));
registerHeaderOperatorConverter(
SearchQuery.DateOperator.class,
(headerName, operator) -> dateRangeFilter(JsonMessageConstants.SENT_DATE, operator));
registerHeaderOperatorConverter(
SearchQuery.ContainsOperator.class,
(headerName, operator) -> matchQuery(JsonMessageConstants.HEADERS + "." + headerName,
operator.getValue()));
}