diff --git a/querydsl-codegen/src/main/java/com/mysema/query/codegen/TypeMappings.java b/querydsl-codegen/src/main/java/com/mysema/query/codegen/TypeMappings.java
index 526f20e6a..f3ba67c19 100644
--- a/querydsl-codegen/src/main/java/com/mysema/query/codegen/TypeMappings.java
+++ b/querydsl-codegen/src/main/java/com/mysema/query/codegen/TypeMappings.java
@@ -14,6 +14,7 @@
 package com.mysema.query.codegen;
 
 import java.util.HashMap;
+import java.util.EnumMap;
 import java.util.Map;
 
 import javax.annotation.Nullable;
@@ -38,11 +39,14 @@ public abstract class TypeMappings {
 
     private final Map<String, Type> queryTypes = new HashMap<String, Type>();
 
-    private final Map<TypeCategory, Type> exprTypes = new HashMap<TypeCategory, Type>();
+    private final Map<TypeCategory, Type> exprTypes
+            = new EnumMap<TypeCategory, Type>(TypeCategory.class);
 
-    private final Map<TypeCategory, Type> pathTypes = new HashMap<TypeCategory, Type>();
+    private final Map<TypeCategory, Type> pathTypes
+            = new EnumMap<TypeCategory, Type>(TypeCategory.class);
 
-    private final Map<TypeCategory, Type> templateTypes = new HashMap<TypeCategory, Type>();
+    private final Map<TypeCategory, Type> templateTypes
+            = new EnumMap<TypeCategory, Type>(TypeCategory.class);
     
     public Type getTemplateType(Type type, EntityType model, boolean raw) {
         return getTemplateType(type, model, raw, false, false);
diff --git a/querydsl-codegen/src/test/java/com/mysema/query/codegen/EmbeddableSerializerTest.java b/querydsl-codegen/src/test/java/com/mysema/query/codegen/EmbeddableSerializerTest.java
index 277ff5d8b..bc0f1acb3 100644
--- a/querydsl-codegen/src/test/java/com/mysema/query/codegen/EmbeddableSerializerTest.java
+++ b/querydsl-codegen/src/test/java/com/mysema/query/codegen/EmbeddableSerializerTest.java
@@ -13,19 +13,20 @@
  */
 package com.mysema.query.codegen;
 
+import static org.junit.Assert.assertTrue;
+
 import java.io.IOException;
 import java.io.StringWriter;
 import java.sql.Time;
 import java.util.Collections;
 import java.util.Date;
-import java.util.HashMap;
+import java.util.EnumMap;
 import java.util.Map;
 
 import com.mysema.codegen.JavaWriter;
 import com.mysema.codegen.model.*;
 import com.mysema.query.annotations.PropertyType;
 import org.junit.Test;
-import static org.junit.Assert.assertTrue;
 
 public class EmbeddableSerializerTest {
 
@@ -57,7 +58,8 @@ public class EmbeddableSerializerTest {
 
     @Test
     public void OriginalCategory() throws IOException{
-        Map<TypeCategory, String> categoryToSuperClass = new HashMap<TypeCategory, String>();
+        Map<TypeCategory, String> categoryToSuperClass
+                = new EnumMap<TypeCategory, String>(TypeCategory.class);
         categoryToSuperClass.put(TypeCategory.COMPARABLE, "ComparablePath<Entity>");
         categoryToSuperClass.put(TypeCategory.ENUM, "EnumPath<Entity>");
         categoryToSuperClass.put(TypeCategory.DATE, "DatePath<Entity>");
diff --git a/querydsl-codegen/src/test/java/com/mysema/query/codegen/EntitySerializerTest.java b/querydsl-codegen/src/test/java/com/mysema/query/codegen/EntitySerializerTest.java
index c6c2f56ce..58c5a2baa 100644
--- a/querydsl-codegen/src/test/java/com/mysema/query/codegen/EntitySerializerTest.java
+++ b/querydsl-codegen/src/test/java/com/mysema/query/codegen/EntitySerializerTest.java
@@ -20,7 +20,7 @@ import java.io.StringWriter;
 import java.sql.Time;
 import java.util.Collections;
 import java.util.Date;
-import java.util.HashMap;
+import java.util.EnumMap;
 import java.util.Map;
 
 import org.junit.Test;
@@ -69,7 +69,6 @@ public class EntitySerializerTest {
         		"extends EntityPathBase<EntitySerializerTest.Entity>"));
     }
     
-
     @Test
     public void No_Package() throws IOException {
         SimpleType type = new SimpleType(TypeCategory.ENTITY, "Entity", "", "Entity",false,false);
@@ -82,7 +81,8 @@ public class EntitySerializerTest {
 
     @Test
     public void OriginalCategory() throws IOException{
-        Map<TypeCategory, String> categoryToSuperClass = new HashMap<TypeCategory, String>();
+        Map<TypeCategory, String> categoryToSuperClass
+                = new EnumMap<TypeCategory, String>(TypeCategory.class);
         categoryToSuperClass.put(TypeCategory.COMPARABLE, "ComparablePath<Entity>");
         categoryToSuperClass.put(TypeCategory.ENUM, "EnumPath<Entity>");
         categoryToSuperClass.put(TypeCategory.DATE, "DatePath<Entity>");