protected boolean applyLabel(JSONSerializer jsonBeanDeser, String label) {
        if (jsonBeanDeser.labelFilters != null) {
            for (LabelFilter propertyFilter : jsonBeanDeser.labelFilters) {
                if (!propertyFilter.apply(label)) {
                    return false;
                }
            }
        }
        
        if (this.labelFilters != null) {
            for (LabelFilter propertyFilter : this.labelFilters) {
                if (!propertyFilter.apply(label)) {
                    return false;
                }
            }
        }
        
        return true;
    }
Get field names of not null fields. Keep the same logic as getSize.

@param object the object to be checked
@return field name set
@throws Exception
@see #getSize(Object)
src/main/java/com/alibaba/fastjson/serializer/JavaBeanSerializer.java