diff --git a/runtime/mirror/class-inl.h b/runtime/mirror/class-inl.h
index 9a6d60e..aa5da2e 100644
--- a/runtime/mirror/class-inl.h
+++ b/runtime/mirror/class-inl.h
@@ -372,7 +372,7 @@
     // to access the field if the FieldId specifies an accessible subclass of the declaring
     // class rather than the declaring class itself.
     ObjPtr<DexCache> referrer_dex_cache = use_referrers_cache ? this->GetDexCache() : dex_cache;
-    uint32_t class_idx = referrer_dex_cache->GetDexFile()->GetFieldId(field_idx).class_idx_;
+    dex::TypeIndex class_idx = referrer_dex_cache->GetDexFile()->GetFieldId(field_idx).class_idx_;
     // The referenced class has already been resolved with the field, but may not be in the dex
     // cache. Use LookupResolveType here to search the class table if it is not in the dex cache.
     // should be no thread suspension due to the class being resolved.
@@ -410,7 +410,7 @@
     // to access the method if the MethodId specifies an accessible subclass of the declaring
     // class rather than the declaring class itself.
     ObjPtr<DexCache> referrer_dex_cache = use_referrers_cache ? this->GetDexCache() : dex_cache;
-    uint32_t class_idx = referrer_dex_cache->GetDexFile()->GetMethodId(method_idx).class_idx_;
+    dex::TypeIndex class_idx = referrer_dex_cache->GetDexFile()->GetMethodId(method_idx).class_idx_;
     // The referenced class has already been resolved with the method, but may not be in the dex
     // cache.
     ObjPtr<Class> dex_access_to = Runtime::Current()->GetClassLinker()->LookupResolvedType(
@@ -894,7 +894,8 @@
   klass->SetClassSize(class_size_);
   klass->SetPrimitiveType(Primitive::kPrimNot);  // Default to not being primitive.
   klass->SetDexClassDefIndex(DexFile::kDexNoIndex16);  // Default to no valid class def index.
-  klass->SetDexTypeIndex(DexFile::kDexNoIndex16);  // Default to no valid type index.
+  klass->SetDexTypeIndex(dex::TypeIndex(DexFile::kDexNoIndex16));  // Default to no valid type
+                                                                   // index.
   // Default to force slow path until initialized.
   klass->SetObjectSizeAllocFastPath(std::numeric_limits<uint32_t>::max());
 }
diff --git a/runtime/mirror/class.cc b/runtime/mirror/class.cc
index db46027..0cfe29b 100644
--- a/runtime/mirror/class.cc
+++ b/runtime/mirror/class.cc
@@ -923,7 +923,7 @@
   return &GetDexFile().GetClassDef(class_def_idx);
 }
 
-uint16_t Class::GetDirectInterfaceTypeIdx(uint32_t idx) {
+dex::TypeIndex Class::GetDirectInterfaceTypeIdx(uint32_t idx) {
   DCHECK(!IsPrimitive());
   DCHECK(!IsArrayClass());
   return GetInterfaceTypeList()->GetTypeItem(idx).type_idx_;
@@ -947,10 +947,11 @@
     DCHECK(interfaces != nullptr);
     return interfaces->Get(idx);
   } else {
-    uint16_t type_idx = klass->GetDirectInterfaceTypeIdx(idx);
+    dex::TypeIndex type_idx = klass->GetDirectInterfaceTypeIdx(idx);
     ObjPtr<Class> interface = klass->GetDexCache()->GetResolvedType(type_idx);
     if (interface == nullptr) {
-      interface = Runtime::Current()->GetClassLinker()->ResolveType(klass->GetDexFile(), type_idx,
+      interface = Runtime::Current()->GetClassLinker()->ResolveType(klass->GetDexFile(),
+                                                                    type_idx,
                                                                     klass.Get());
       CHECK(interface != nullptr || self->IsExceptionPending());
     }
@@ -1130,10 +1131,12 @@
   return depth;
 }
 
-uint32_t Class::FindTypeIndexInOtherDexFile(const DexFile& dex_file) {
+dex::TypeIndex Class::FindTypeIndexInOtherDexFile(const DexFile& dex_file) {
   std::string temp;
   const DexFile::TypeId* type_id = dex_file.FindTypeId(GetDescriptor(&temp));
-  return (type_id == nullptr) ? DexFile::kDexNoIndex : dex_file.GetIndexForTypeId(*type_id);
+  return (type_id == nullptr)
+      ? dex::TypeIndex(DexFile::kDexNoIndex)
+      : dex_file.GetIndexForTypeId(*type_id);
 }
 
 template <PointerSize kPointerSize, bool kTransactionActive>
diff --git a/runtime/mirror/class.h b/runtime/mirror/class.h
index 711914d..792f626 100644
--- a/runtime/mirror/class.h
+++ b/runtime/mirror/class.h
@@ -20,6 +20,7 @@
 #include "base/enums.h"
 #include "base/iteration_range.h"
 #include "dex_file.h"
+#include "dex_file_types.h"
 #include "class_flags.h"
 #include "gc_root.h"
 #include "gc/allocator_type.h"
@@ -1148,16 +1149,17 @@
     SetField32<false>(OFFSET_OF_OBJECT_MEMBER(Class, dex_class_def_idx_), class_def_idx);
   }
 
-  uint16_t GetDexTypeIndex() REQUIRES_SHARED(Locks::mutator_lock_) {
-    return GetField32(OFFSET_OF_OBJECT_MEMBER(Class, dex_type_idx_));
+  dex::TypeIndex GetDexTypeIndex() REQUIRES_SHARED(Locks::mutator_lock_) {
+    return dex::TypeIndex(
+        static_cast<uint16_t>(GetField32(OFFSET_OF_OBJECT_MEMBER(Class, dex_type_idx_))));
   }
 
-  void SetDexTypeIndex(uint16_t type_idx) REQUIRES_SHARED(Locks::mutator_lock_) {
+  void SetDexTypeIndex(dex::TypeIndex type_idx) REQUIRES_SHARED(Locks::mutator_lock_) {
     // Not called within a transaction.
-    SetField32<false>(OFFSET_OF_OBJECT_MEMBER(Class, dex_type_idx_), type_idx);
+    SetField32<false>(OFFSET_OF_OBJECT_MEMBER(Class, dex_type_idx_), type_idx.index_);
   }
 
-  uint32_t FindTypeIndexInOtherDexFile(const DexFile& dex_file)
+  dex::TypeIndex FindTypeIndexInOtherDexFile(const DexFile& dex_file)
       REQUIRES_SHARED(Locks::mutator_lock_);
 
   static Class* GetJavaLangClass() REQUIRES_SHARED(Locks::mutator_lock_) {
@@ -1198,7 +1200,7 @@
 
   ALWAYS_INLINE uint32_t NumDirectInterfaces() REQUIRES_SHARED(Locks::mutator_lock_);
 
-  uint16_t GetDirectInterfaceTypeIdx(uint32_t idx) REQUIRES_SHARED(Locks::mutator_lock_);
+  dex::TypeIndex GetDirectInterfaceTypeIdx(uint32_t idx) REQUIRES_SHARED(Locks::mutator_lock_);
 
   static ObjPtr<Class> GetDirectInterface(Thread* self,
                                           Handle<Class> klass,
diff --git a/runtime/mirror/dex_cache-inl.h b/runtime/mirror/dex_cache-inl.h
index c7a123b..d903f71 100644
--- a/runtime/mirror/dex_cache-inl.h
+++ b/runtime/mirror/dex_cache-inl.h
@@ -69,15 +69,15 @@
   }
 }
 
-inline Class* DexCache::GetResolvedType(uint32_t type_idx) {
-  DCHECK_LT(type_idx, NumResolvedTypes());
-  return GetResolvedTypes()[type_idx].Read();
+inline Class* DexCache::GetResolvedType(dex::TypeIndex type_idx) {
+  DCHECK_LT(type_idx.index_, NumResolvedTypes());
+  return GetResolvedTypes()[type_idx.index_].Read();
 }
 
-inline void DexCache::SetResolvedType(uint32_t type_idx, ObjPtr<Class> resolved) {
-  DCHECK_LT(type_idx, NumResolvedTypes());  // NOTE: Unchecked, i.e. not throwing AIOOB.
+inline void DexCache::SetResolvedType(dex::TypeIndex type_idx, ObjPtr<Class> resolved) {
+  DCHECK_LT(type_idx.index_, NumResolvedTypes());  // NOTE: Unchecked, i.e. not throwing AIOOB.
   // TODO default transaction support.
-  GetResolvedTypes()[type_idx] = GcRoot<Class>(resolved);
+  GetResolvedTypes()[type_idx.index_] = GcRoot<Class>(resolved);
   // TODO: Fine-grained marking, so that we don't need to go through all arrays in full.
   Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(this);
 }
diff --git a/runtime/mirror/dex_cache.h b/runtime/mirror/dex_cache.h
index 1ae694d..7d82d3a 100644
--- a/runtime/mirror/dex_cache.h
+++ b/runtime/mirror/dex_cache.h
@@ -21,6 +21,7 @@
 #include "art_field.h"
 #include "art_method.h"
 #include "class.h"
+#include "dex_file_types.h"
 #include "object.h"
 #include "object_array.h"
 
@@ -223,9 +224,9 @@
   // the string isn't kept live.
   void ClearString(uint32_t string_idx) REQUIRES_SHARED(Locks::mutator_lock_);
 
-  Class* GetResolvedType(uint32_t type_idx) REQUIRES_SHARED(Locks::mutator_lock_);
+  Class* GetResolvedType(dex::TypeIndex type_idx) REQUIRES_SHARED(Locks::mutator_lock_);
 
-  void SetResolvedType(uint32_t type_idx, ObjPtr<Class> resolved)
+  void SetResolvedType(dex::TypeIndex type_idx, ObjPtr<Class> resolved)
       REQUIRES_SHARED(Locks::mutator_lock_);
 
   ALWAYS_INLINE ArtMethod* GetResolvedMethod(uint32_t method_idx, PointerSize ptr_size)
diff --git a/runtime/mirror/object_test.cc b/runtime/mirror/object_test.cc
index 5bf254d..4b47f7f 100644
--- a/runtime/mirror/object_test.cc
+++ b/runtime/mirror/object_test.cc
@@ -313,7 +313,7 @@
   ArtMethod* sort = java_util_Arrays->FindDirectMethod("sort", "([I)V", kRuntimePointerSize);
   const DexFile::TypeId* type_id = java_lang_dex_file_->FindTypeId("[I");
   ASSERT_TRUE(type_id != nullptr);
-  uint32_t type_idx = java_lang_dex_file_->GetIndexForTypeId(*type_id);
+  dex::TypeIndex type_idx = java_lang_dex_file_->GetIndexForTypeId(*type_id);
   Object* array = CheckAndAllocArrayFromCodeInstrumented(
       type_idx, 3, sort, Thread::Current(), false,
       Runtime::Current()->GetHeap()->GetCurrentAllocator());