diff --git a/build.gradle b/build.gradle
index 2700576..506bf90 100644
--- a/build.gradle
+++ b/build.gradle
@@ -39,7 +39,7 @@ repositories {
 
 
 dependencies {
-    compile "com.graphql-java:graphql-java:13.0"
+    compile "com.graphql-java:graphql-java:14.0"
     compile 'org.slf4j:slf4j-api:1.7.25'
     compile "javax.validation:validation-api:2.0.1.Final"
     compile "org.hibernate.validator:hibernate-validator:6.0.17.Final"
diff --git a/src/main/java/graphql/validation/constraints/AbstractDirectiveConstraint.java b/src/main/java/graphql/validation/constraints/AbstractDirectiveConstraint.java
index ebc13e0..3d3dd08 100644
--- a/src/main/java/graphql/validation/constraints/AbstractDirectiveConstraint.java
+++ b/src/main/java/graphql/validation/constraints/AbstractDirectiveConstraint.java
@@ -10,6 +10,7 @@
 import graphql.schema.GraphQLFieldsContainer;
 import graphql.schema.GraphQLInputObjectType;
 import graphql.schema.GraphQLInputType;
+import graphql.schema.GraphQLNamedInputType;
 import graphql.schema.GraphQLScalarType;
 import graphql.schema.GraphQLTypeUtil;
 import graphql.validation.rules.ValidationEnvironment;
@@ -162,7 +163,7 @@ private List<GraphQLError> runConstraintOnDirectives(ValidationEnvironment valid
      * @return true ifits oneof them
      */
     protected boolean isOneOfTheseTypes(GraphQLInputType inputType, GraphQLScalarType... scalarTypes) {
-        GraphQLInputType unwrappedType = Util.unwrapNonNull(inputType);
+        GraphQLNamedInputType unwrappedType = Util.unwrapNonNullNamedType(inputType);
         for (GraphQLScalarType scalarType : scalarTypes) {
             if (unwrappedType.getName().equals(scalarType.getName())) {
                 return true;
diff --git a/src/main/java/graphql/validation/util/Util.java b/src/main/java/graphql/validation/util/Util.java
index 31373fa..801e265 100644
--- a/src/main/java/graphql/validation/util/Util.java
+++ b/src/main/java/graphql/validation/util/Util.java
@@ -6,6 +6,7 @@
 import graphql.execution.DataFetcherResult;
 import graphql.execution.ExecutionPath;
 import graphql.schema.GraphQLInputType;
+import graphql.schema.GraphQLNamedInputType;
 import graphql.schema.GraphQLType;
 import graphql.schema.GraphQLTypeUtil;
 
@@ -40,6 +41,16 @@ public static GraphQLInputType unwrapOneAndAllNonNull(GraphQLInputType inputType
         }
     }
 
+    public static GraphQLNamedInputType unwrapNonNullNamedType(GraphQLInputType inputType) {
+        GraphQLType type = GraphQLTypeUtil.unwrapNonNull(inputType);
+        if (type instanceof GraphQLNamedInputType) {
+            return (GraphQLNamedInputType) type;
+        } else {
+            String argType = GraphQLTypeUtil.simplePrint(inputType);
+            return Assert.assertShouldNeverHappen("You have a wrapped type that is in fact not a input type : %s", argType);
+        }
+    }
+
     public static GraphQLInputType unwrapNonNull(GraphQLInputType inputType) {
         GraphQLType type = GraphQLTypeUtil.unwrapNonNull(inputType);
         if (type instanceof GraphQLInputType) {