recreating the netflix Intern field names PR

src/main/java/graphql/language/Field.java

@@ -6,6 +6,7 @@
 import graphql.Internal;
 import graphql.PublicApi;
 import graphql.collect.ImmutableKit;
+import graphql.util.FieldNameInterner;
 import graphql.util.TraversalControl;
 import graphql.util.TraverserContext;
 
@@ -50,8 +51,8 @@ protected Field(String name,
                     IgnoredChars ignoredChars,
                     Map<String, String> additionalData) {
         super(sourceLocation, comments, ignoredChars, additionalData);
-        this.name = name;
-        this.alias = alias;
+        this.name = name == null ? null : FieldNameInterner.intern(name);
+        this.alias = alias == null ? null : FieldNameInterner.intern(alias);
         this.arguments = ImmutableList.copyOf(arguments);
         this.directives = ImmutableList.copyOf(directives);
         this.selectionSet = selectionSet;

src/main/java/graphql/schema/GraphQLFieldDefinition.java

@@ -6,6 +6,7 @@
 import graphql.Internal;
 import graphql.PublicApi;
 import graphql.language.FieldDefinition;
+import graphql.util.FieldNameInterner;
 import graphql.util.TraversalControl;
 import graphql.util.TraverserContext;
 
@@ -61,7 +62,7 @@ private GraphQLFieldDefinition(String name,
         assertValidName(name);
         assertNotNull(type, () -> "type can't be null");
         assertNotNull(arguments, () -> "arguments can't be null");
-        this.name = name;
+        this.name = FieldNameInterner.intern(name);
         this.description = description;
         this.originalType = type;
         this.dataFetcherFactory = dataFetcherFactory;

src/main/java/graphql/schema/GraphQLInterfaceType.java

@@ -51,7 +51,6 @@ public class GraphQLInterfaceType implements GraphQLNamedType, GraphQLCompositeT
     private final Comparator<? super GraphQLSchemaElement> interfaceComparator;
     private ImmutableList<GraphQLNamedOutputType> replacedInterfaces;
 
-
     public static final String CHILD_FIELD_DEFINITIONS = "fieldDefinitions";
     public static final String CHILD_INTERFACES = "interfaces";
 
@@ -96,7 +95,6 @@ public GraphQLFieldDefinition getFieldDefinition(String name) {
         return fieldDefinitionsByName.get(name);
     }
 
-
     @Override
     public List<GraphQLFieldDefinition> getFieldDefinitions() {
         return ImmutableList.copyOf(fieldDefinitionsByName.values());
@@ -229,9 +227,9 @@ public GraphQLInterfaceType withNewChildren(SchemaElementChildrenContainer newCh
     @Override
     public List<GraphQLNamedOutputType> getInterfaces() {
         if (replacedInterfaces != null) {
-            return ImmutableList.copyOf(replacedInterfaces);
+            return replacedInterfaces;
         }
-        return ImmutableList.copyOf(originalInterfaces);
+        return originalInterfaces;
     }
 
     void replaceInterfaces(List<GraphQLNamedOutputType> interfaces) {

src/main/java/graphql/schema/GraphQLObjectType.java

@@ -40,7 +40,6 @@
 @PublicApi
 public class GraphQLObjectType implements GraphQLNamedOutputType, GraphQLCompositeType, GraphQLUnmodifiedType, GraphQLNullableType, GraphQLDirectiveContainer, GraphQLImplementingType {
 
-
     private final String name;
     private final String description;
     private final Comparator<? super GraphQLSchemaElement> interfaceComparator;
@@ -132,7 +131,6 @@ public List<GraphQLFieldDefinition> getFieldDefinitions() {
         return ImmutableList.copyOf(fieldDefinitionsByName.values());
     }
 
-
     @Override
     public List<GraphQLNamedOutputType> getInterfaces() {
         if (replacedInterfaces != null) {

src/main/java/graphql/util/FieldNameInterner.java

@@ -0,0 +1,22 @@
+package graphql.util;
+
+import com.google.common.collect.Interner;
+import com.google.common.collect.Interners;
+import graphql.Internal;
+
+/**
+ * Interner allowing object identity based comparison of field names.
+ */
+@Internal
+public class FieldNameInterner {
+
+    private FieldNameInterner() {
+    }
+
+    public static final Interner<String> INTERNER = Interners.newWeakInterner();
+
+    public static String intern(String name) {
+        return INTERNER.intern(name);
+    }
+
+}