diff --git a/processor/src/main/java/org/mapstruct/ap/model/Type.java b/processor/src/main/java/org/mapstruct/ap/model/Type.java
index 8ba814cd0..bcc2bd769 100644
--- a/processor/src/main/java/org/mapstruct/ap/model/Type.java
+++ b/processor/src/main/java/org/mapstruct/ap/model/Type.java
@@ -148,6 +148,21 @@ public class Type extends AbstractModelElement implements Comparable<Type> {
             Collections.<Type>emptySet();
     }
 
+    /**
+     * Whether this type is assignable to the given other type.
+     *
+     * @param other The other type.
+     *
+     * @return {@code true} if and only if this type is assignable to the given other type.
+     */
+    public boolean isAssignableTo(Type other) {
+        if ( equals( other ) ) {
+            return true;
+        }
+
+        return typeUtils.isAssignable( typeMirror, other.typeMirror );
+    }
+
     @Override
     public int hashCode() {
         final int prime = 31;
diff --git a/processor/src/main/java/org/mapstruct/ap/processor/MethodRetrievalProcessor.java b/processor/src/main/java/org/mapstruct/ap/processor/MethodRetrievalProcessor.java
index 7cdfa39b0..ce93eb171 100644
--- a/processor/src/main/java/org/mapstruct/ap/processor/MethodRetrievalProcessor.java
+++ b/processor/src/main/java/org/mapstruct/ap/processor/MethodRetrievalProcessor.java
@@ -207,7 +207,7 @@ public class MethodRetrievalProcessor implements ModelElementProcessor<Void, Lis
         }
 
         if ( returnType.getTypeMirror().getKind() != TypeKind.VOID &&
-            !typeFactory.isAssignable( resultType, returnType ) ) {
+            !resultType.isAssignableTo( returnType ) ) {
             messager.printMessage(
                 Kind.ERROR,
                 "The result type is not assignable to the the return type.",
diff --git a/processor/src/main/java/org/mapstruct/ap/util/TypeFactory.java b/processor/src/main/java/org/mapstruct/ap/util/TypeFactory.java
index 9a404498b..d800b4265 100644
--- a/processor/src/main/java/org/mapstruct/ap/util/TypeFactory.java
+++ b/processor/src/main/java/org/mapstruct/ap/util/TypeFactory.java
@@ -173,20 +173,4 @@ public class TypeFactory {
 
         return null;
     }
-
-    /**
-     * @param type1 first type
-     * @param type2 second type
-     *
-     * @return {@code true} if and only if the first type is assignable to the second
-     */
-    public boolean isAssignable(Type type1, Type type2) {
-        if ( type1.equals( type2 ) ) {
-            return true;
-        }
-
-        TypeMirror mirror1 = type1.getTypeMirror();
-        TypeMirror mirror2 = type2.getTypeMirror();
-        return null != mirror1 && null != mirror2 && typeUtils.isAssignable( mirror1, mirror2 );
-    }
 }