synchronized (SearchableConvertUtils.class) {
if (conversionService == null) {
try {
conversionService = SpringUtils.getBean(ConversionService.class);
} catch (Exception e) {
throw new SearchException("conversionService is null, " +
"search param convert must use conversionService. " +
"please see [com.sishuok.es.common.entity.search.utils." +
"SearchableConvertUtils#setConversionService]");
}
}