diff --git a/jOOQ-codegen/src/main/java/org/jooq/codegen/JavaGenerator.java b/jOOQ-codegen/src/main/java/org/jooq/codegen/JavaGenerator.java
index d262efbe2e..9c6ab73397 100644
--- a/jOOQ-codegen/src/main/java/org/jooq/codegen/JavaGenerator.java
+++ b/jOOQ-codegen/src/main/java/org/jooq/codegen/JavaGenerator.java
@@ -9679,6 +9679,8 @@ public class JavaGenerator extends AbstractGenerator {
         else if (db.getDomain(schema, u) != null) {
             sb.append(getStrategy().getFullJavaIdentifier(db.getDomain(schema, u)));
             sb.append(".getDataType()");
+
+            appendTypeReferenceNullability(sb, n);
         }
         else if (db.getUDT(schema, u) != null) {
             sb.append(getStrategy().getFullJavaIdentifier(db.getUDT(schema, u)));
@@ -9773,8 +9775,7 @@ public class JavaGenerator extends AbstractGenerator {
                     sb.append(sqlDataTypeRef);
             }
 
-            if (!dataType.nullable())
-                sb.append(".nullable(false)");
+            appendTypeReferenceNullability(sb, n);
 
             if (dataType.identity())
                 sb.append(".identity(true)");
@@ -9841,6 +9842,11 @@ public class JavaGenerator extends AbstractGenerator {
         return sb.toString();
     }
 
+    private final void appendTypeReferenceNullability(StringBuilder sb, boolean n) {
+        if (!n)
+            sb.append(".nullable(false)");
+    }
+
     private DataType<?> mapTypes(DataType<?> dataType) {
         DataType<?> result = dataType;
 
diff --git a/jOOQ/src/main/java/org/jooq/impl/DataTypeProxy.java b/jOOQ/src/main/java/org/jooq/impl/DataTypeProxy.java
index 7c3d6fd01b..3ec3f215cf 100644
--- a/jOOQ/src/main/java/org/jooq/impl/DataTypeProxy.java
+++ b/jOOQ/src/main/java/org/jooq/impl/DataTypeProxy.java
@@ -80,7 +80,6 @@ final class DataTypeProxy<T> extends AbstractDataType<T> {
         this(type, null, null, null, null, null, null, null, null, null, null, null, null);
     }
 
-    @SuppressWarnings("unchecked")
     private DataTypeProxy(
         AbstractDataType<T> type,
         Integer overridePrecision,
diff --git a/jOOQ/src/main/java/org/jooq/impl/DomainDataType.java b/jOOQ/src/main/java/org/jooq/impl/DomainDataType.java
index b2ea5e7d1c..fe857a9a8a 100644
--- a/jOOQ/src/main/java/org/jooq/impl/DomainDataType.java
+++ b/jOOQ/src/main/java/org/jooq/impl/DomainDataType.java
@@ -37,9 +37,16 @@
  */
 package org.jooq.impl;
 
+import org.jooq.CharacterSet;
+import org.jooq.Collation;
 import org.jooq.Configuration;
 import org.jooq.DataType;
 import org.jooq.Domain;
+import org.jooq.Field;
+import org.jooq.Generator;
+import org.jooq.Nullability;
+import org.jooq.impl.QOM.GenerationLocation;
+import org.jooq.impl.QOM.GenerationOption;
 
 /**
  * A <code>DataType</code> used for {@link Domain} types.
@@ -78,6 +85,40 @@ final class DomainDataType<T> extends DefaultDataType<T> {
         this.baseType = baseType;
     }
 
+    @Override
+    DefaultDataType<T> construct(
+        Integer newPrecision,
+        Integer newScale,
+        Integer newLength,
+        Nullability newNullability,
+        boolean newReadonly,
+        Generator<?, ?, T> newGeneratedAlwaysAs,
+        GenerationOption newGenerationOption,
+        GenerationLocation newGenerationLocation,
+        Collation newCollation,
+        CharacterSet newCharacterSet,
+        boolean newIdentity,
+        Field<T> newDefaultValue
+    ) {
+        return new DomainDataType<>(
+            domain,
+            ((AbstractDataTypeX<T>) baseType).construct(
+                newPrecision,
+                newScale,
+                newLength,
+                newNullability,
+                newReadonly,
+                newGeneratedAlwaysAs,
+                newGenerationOption,
+                newGenerationLocation,
+                newCollation,
+                newCharacterSet,
+                newIdentity,
+                newDefaultValue
+            )
+        );
+    }
+
     @Override
     public final Domain<T> getDomain() {
         return domain;