diff --git a/src/main/java/dev/struchkov/haiti/filter/jooq/CriteriaJooqFilter.java b/src/main/java/dev/struchkov/haiti/filter/jooq/CriteriaJooqFilter.java
index 8737766..b82609e 100644
--- a/src/main/java/dev/struchkov/haiti/filter/jooq/CriteriaJooqFilter.java
+++ b/src/main/java/dev/struchkov/haiti/filter/jooq/CriteriaJooqFilter.java
@@ -111,8 +111,7 @@ public class CriteriaJooqFilter {
     }
 
     public CriteriaJooqFilter sort(SortContainer container) {
-        Assert.isNotNull(container);
-        if (container.getFieldName() != null) {
+        if (container != null && container.getFieldName() != null) {
             this.sorts.add(container);
         }
         return this;
diff --git a/src/main/java/dev/struchkov/haiti/filter/jooq/sort/SortContainer.java b/src/main/java/dev/struchkov/haiti/filter/jooq/sort/SortContainer.java
index 6bd1b7f..e1ce9f3 100644
--- a/src/main/java/dev/struchkov/haiti/filter/jooq/sort/SortContainer.java
+++ b/src/main/java/dev/struchkov/haiti/filter/jooq/sort/SortContainer.java
@@ -17,10 +17,6 @@ public class SortContainer {
         this.type = type;
     }
 
-    public static SortContainer empty() {
-        return new SortContainer(null);
-    }
-
     public static SortContainer of(String fieldName) {
         Assert.isNotNull(fieldName);
         return new SortContainer(fieldName);