private AjaxRequestBuilder addExpressions(UIComponent component, String expressions, String key, Set<SearchExpressionHint> hints) {
        if (LangUtils.isNotBlank(expressions)) {
            String resolvedExpressions = SearchExpressionUtils.resolveClientIdsAsString(context, component, expressions, hints,
                    null);
            buffer.append(",").append(key).append(":\"").append(resolvedExpressions).append("\"");
        }

        return this;
    }
Helper to generate javascript code of an ajax call
primefaces/src/main/java/org/primefaces/util/AjaxRequestBuilder.java