diff --git a/java/core/src/main/java/com/google/protobuf/Internal.java b/java/core/src/main/java/com/google/protobuf/Internal.java
index 3024aa9dfb39..07bec5ef29d7 100644
--- a/java/core/src/main/java/com/google/protobuf/Internal.java
+++ b/java/core/src/main/java/com/google/protobuf/Internal.java
@@ -371,6 +371,36 @@ static Object mergeMessage(Object destination, Object source) {
     return ((MessageLite) destination).toBuilder().mergeFrom((MessageLite) source).buildPartial();
   }
 
+  /**
+   * Provides an immutable view of {@code List<T>} around an {@code IntList}.
+   *
+   * <p>Protobuf internal. Used in protobuf generated code only.
+   */
+  public static class IntListAdapter<T> extends AbstractList<T> {
+    /** Convert individual elements of the List from int to T. */
+    public interface IntConverter<T> {
+      T convert(int from);
+    }
+
+    private final IntList fromList;
+    private final IntConverter<T> converter;
+
+    public IntListAdapter(IntList fromList, IntConverter<T> converter) {
+      this.fromList = fromList;
+      this.converter = converter;
+    }
+
+    @Override
+    public T get(int index) {
+      return converter.convert(fromList.getInt(index));
+    }
+
+    @Override
+    public int size() {
+      return fromList.size();
+    }
+  }
+
   /**
    * Provides an immutable view of {@code List<T>} around a {@code List<F>}.
    *
diff --git a/src/google/protobuf/compiler/java/lite/enum_field.cc b/src/google/protobuf/compiler/java/lite/enum_field.cc
index f2fb340b1b27..3e86e1942fff 100644
--- a/src/google/protobuf/compiler/java/lite/enum_field.cc
+++ b/src/google/protobuf/compiler/java/lite/enum_field.cc
@@ -597,12 +597,12 @@ void RepeatedImmutableEnumFieldLiteGenerator::GenerateMembers(
       variables_,
       "private com.google.protobuf.Internal.IntList $name$_;\n"
       "private static final "
-      "com.google.protobuf.Internal.ListAdapter.Converter<\n"
-      "    java.lang.Integer, $type$> $name$_converter_ =\n"
-      "        new com.google.protobuf.Internal.ListAdapter.Converter<\n"
-      "            java.lang.Integer, $type$>() {\n"
+      "com.google.protobuf.Internal.IntListAdapter.IntConverter<\n"
+      "    $type$> $name$_converter_ =\n"
+      "        new com.google.protobuf.Internal.IntListAdapter.IntConverter<\n"
+      "            $type$>() {\n"
       "          @java.lang.Override\n"
-      "          public $type$ convert(java.lang.Integer from) {\n"
+      "          public $type$ convert(int from) {\n"
       "            $type$ result = $type$.forNumber(from);\n"
       "            return result == null ? $unknown$ : result;\n"
       "          }\n"
@@ -610,14 +610,13 @@ void RepeatedImmutableEnumFieldLiteGenerator::GenerateMembers(
   PrintExtraFieldInfo(variables_, printer);
   WriteFieldAccessorDocComment(printer, descriptor_, LIST_GETTER,
                                context_->options());
-  printer->Print(
-      variables_,
-      "@java.lang.Override\n"
-      "$deprecation$public java.util.List<$type$> "
-      "${$get$capitalized_name$List$}$() {\n"
-      "  return new com.google.protobuf.Internal.ListAdapter<\n"
-      "      java.lang.Integer, $type$>($name$_, $name$_converter_);\n"
-      "}\n");
+  printer->Print(variables_,
+                 "@java.lang.Override\n"
+                 "$deprecation$public java.util.List<$type$> "
+                 "${$get$capitalized_name$List$}$() {\n"
+                 "  return new com.google.protobuf.Internal.IntListAdapter<\n"
+                 "      $type$>($name$_, $name$_converter_);\n"
+                 "}\n");
   printer->Annotate("{", "}", descriptor_);
   WriteFieldAccessorDocComment(printer, descriptor_, LIST_COUNT,
                                context_->options());