Merge pull request #16722 from protocolbuffers/cp-java-generator

Cherry pick java_features.proto boostrap and java generator refactor

pkg/BUILD.bazel

@@ -198,6 +198,7 @@ cc_dist_library(
         "//src/google/protobuf/compiler/cpp",
         "//src/google/protobuf/compiler/csharp",
         "//src/google/protobuf/compiler/java",
+        "//src/google/protobuf/compiler/java:kotlin",
         "//src/google/protobuf/compiler/objectivec",
         "//src/google/protobuf/compiler/php",
         "//src/google/protobuf/compiler/python",

src/file_lists.cmake

@@ -330,36 +330,40 @@ set(libprotoc_srcs
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/csharp/names.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/context.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/doc_comment.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/field_common.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum_field.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum_field_lite.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum_lite.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/extension.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/extension_lite.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/field.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/file.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/generator.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/generator_factory.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/helpers.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/enum.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/enum_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/extension.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/generator_factory.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/make_field_generators.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/map_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/message.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/message_builder.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/message_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/primitive_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/service.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/string_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/internal_helpers.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/java_features.pb.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/kotlin_generator.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/map_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/enum.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/map_field_lite.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/enum_field.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/extension.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_builder.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/generator_factory.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_builder_lite.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/make_field_generators.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/map_field.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_field_lite.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/message.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_lite.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/message_builder.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/message_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/primitive_field.cc
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/string_field.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_serialization.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/name_resolver.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/names.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/primitive_field.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/primitive_field_lite.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/service.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/shared_code_generator.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/string_field.cc
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/string_field_lite.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/objectivec/enum.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/objectivec/enum_field.cc
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/objectivec/extension.cc
@@ -452,37 +456,45 @@ set(libprotoc_hdrs
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/csharp/names.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/context.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/doc_comment.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/field_common.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum_field.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum_field_lite.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/enum_lite.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/extension.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/extension_lite.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/field.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/file.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/generator.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/generator_common.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/generator_factory.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/helpers.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/enum.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/enum_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/extension.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/field_generator.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/generator_factory.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/make_field_generators.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/map_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/message.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/message_builder.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/message_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/primitive_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/service.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/immutable/string_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/internal_helpers.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/java_features.pb.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/kotlin_generator.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/map_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/enum.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/map_field_lite.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/enum_field.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/extension.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_builder.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/field_generator.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_builder_lite.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/generator_factory.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/make_field_generators.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_field_lite.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/map_field.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_lite.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/message.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/message_builder.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/message_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/primitive_field.h
+  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/lite/string_field.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/message_serialization.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/name_resolver.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/names.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/options.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/primitive_field.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/primitive_field_lite.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/service.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/shared_code_generator.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/string_field.h
-  ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/java/string_field_lite.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/objectivec/enum.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/objectivec/enum_field.h
   ${protobuf_SOURCE_DIR}/src/google/protobuf/compiler/objectivec/extension.h

src/google/protobuf/compiler/BUILD.bazel

@@ -195,6 +195,7 @@ cc_library(
         "//src/google/protobuf/compiler/cpp",
         "//src/google/protobuf/compiler/csharp",
         "//src/google/protobuf/compiler/java",
+        "//src/google/protobuf/compiler/java:kotlin",
         "//src/google/protobuf/compiler/objectivec",
         "//src/google/protobuf/compiler/php",
         "//src/google/protobuf/compiler/python",

src/google/protobuf/compiler/java/BUILD.bazel

@@ -6,6 +6,12 @@ load("@rules_cc//cc:defs.bzl", "cc_library", "cc_test")
 load("@rules_pkg//pkg:mappings.bzl", "pkg_files", "strip_prefix")
 load("//build_defs:cpp_opts.bzl", "COPTS")
 
+package(
+    default_visibility = [
+        "//src/google/protobuf/compiler/java:__subpackages__",
+    ],
+)
+
 cc_library(
     name = "names",
     hdrs = ["names.h"],
@@ -13,20 +19,22 @@ cc_library(
     strip_include_prefix = "/src",
     visibility = ["//visibility:public"],
     deps = [
-        ":names_internal",
+        ":helpers",
         "//src/google/protobuf",
     ],
 )
 
 cc_library(
-    name = "names_internal",
+    name = "helpers",
     srcs = [
+        "doc_comment.cc",
         "helpers.cc",
         "name_resolver.cc",
         "names.cc",
     ],
     hdrs = [
-        "generator.h",
+        "context.h",
+        "doc_comment.h",
         "helpers.h",
         "name_resolver.h",
         "names.h",
@@ -34,9 +42,11 @@ cc_library(
     ],
     copts = COPTS,
     strip_include_prefix = "/src",
-    visibility = ["//pkg:__pkg__"],
+    visibility = [
+        "//pkg:__pkg__",
+        "//src/google/protobuf/compiler/java:__subpackages__",
+    ],
     deps = [
-        ":java_features_bootstrap",
         "//src/google/protobuf",
         "//src/google/protobuf:port",
         "//src/google/protobuf/compiler:code_generator",
@@ -52,6 +62,25 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "internal_helpers",
+    srcs = ["internal_helpers.cc"],
+    hdrs = [
+        "generator.h",
+        "internal_helpers.h",
+    ],
+    strip_include_prefix = "/src",
+    visibility = ["//src/google/protobuf/compiler/java:__subpackages__"],
+    deps = [
+        ":helpers",
+        ":java_features_bootstrap",
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler:code_generator",
+        "@com_google_absl//absl/log:absl_log",
+    ],
+)
+
 cc_library(
     name = "java_features_bootstrap",
     srcs = ["java_features.pb.cc"],
@@ -70,64 +99,16 @@ cc_library(
     name = "java",
     srcs = [
         "context.cc",
-        "doc_comment.cc",
-        "enum.cc",
-        "enum_field.cc",
-        "enum_field_lite.cc",
-        "enum_lite.cc",
-        "extension.cc",
-        "extension_lite.cc",
-        "field.cc",
         "file.cc",
         "generator.cc",
-        "generator_factory.cc",
-        "kotlin_generator.cc",
-        "map_field.cc",
-        "map_field_lite.cc",
-        "message.cc",
-        "message_builder.cc",
-        "message_builder_lite.cc",
-        "message_field.cc",
-        "message_field_lite.cc",
-        "message_lite.cc",
-        "message_serialization.cc",
-        "primitive_field.cc",
-        "primitive_field_lite.cc",
-        "service.cc",
         "shared_code_generator.cc",
-        "string_field.cc",
-        "string_field_lite.cc",
     ],
     hdrs = [
-        "context.h",
-        "doc_comment.h",
-        "enum.h",
-        "enum_field.h",
-        "enum_field_lite.h",
-        "enum_lite.h",
-        "extension.h",
-        "extension_lite.h",
-        "field.h",
         "file.h",
         "generator.h",
         "generator_factory.h",
         "java_features.pb.h",
-        "kotlin_generator.h",
-        "map_field.h",
-        "map_field_lite.h",
-        "message.h",
-        "message_builder.h",
-        "message_builder_lite.h",
-        "message_field.h",
-        "message_field_lite.h",
-        "message_lite.h",
-        "message_serialization.h",
-        "primitive_field.h",
-        "primitive_field_lite.h",
-        "service.h",
         "shared_code_generator.h",
-        "string_field.h",
-        "string_field_lite.h",
     ],
     copts = COPTS,
     strip_include_prefix = "/src",
@@ -136,9 +117,10 @@ cc_library(
         "//src/google/protobuf/compiler:__pkg__",
     ],
     deps = [
+        ":generator_common",
+        ":helpers",
         ":java_features_bootstrap",
         ":names",
-        ":names_internal",
         "//src/google/protobuf",
         "//src/google/protobuf:arena",
         "//src/google/protobuf:port",
@@ -146,6 +128,8 @@ cc_library(
         "//src/google/protobuf/compiler:code_generator",
         "//src/google/protobuf/compiler:retention",
         "//src/google/protobuf/compiler:versions",
+        "//src/google/protobuf/compiler/java/immutable",
+        "//src/google/protobuf/compiler/java/lite",
         "//src/google/protobuf/io",
         "//src/google/protobuf/io:printer",
         "@com_google_absl//absl/container:btree",
@@ -158,6 +142,62 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "generator_common",
+    srcs = ["field_common.cc"],
+    hdrs = [
+        "field_common.h",
+        "generator_common.h",
+        "generator_factory.h",
+    ],
+    strip_include_prefix = "/src",
+    visibility = ["//src/google/protobuf/compiler/java:__subpackages__"],
+    deps = [
+        ":helpers",
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/container:btree",
+        "@com_google_absl//absl/container:flat_hash_map",
+        "@com_google_absl//absl/log:absl_check",
+        "@com_google_absl//absl/log:absl_log",
+        "@com_google_absl//absl/strings:string_view",
+    ],
+)
+
+cc_library(
+    name = "message_serialization",
+    srcs = ["message_serialization.cc"],
+    hdrs = ["message_serialization.h"],
+    strip_include_prefix = "/src",
+    deps = [
+        ":generator_common",
+        ":helpers",
+        "//src/google/protobuf",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/strings",
+        "@com_google_absl//absl/types:span",
+    ],
+)
+
+cc_library(
+    name = "kotlin",
+    srcs = ["kotlin_generator.cc"],
+    hdrs = ["kotlin_generator.h"],
+    strip_include_prefix = "/src",
+    visibility = [
+        "//pkg:__pkg__",
+        "//src/google/protobuf/compiler:__pkg__",
+    ],
+    deps = [
+        ":helpers",
+        ":java",
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler:code_generator",
+    ],
+)
+
 cc_test(
     name = "doc_comment_unittest",
     srcs = ["doc_comment_unittest.cc"],
@@ -167,7 +207,7 @@ cc_test(
         "//src/google/protobuf:descriptor_proto_srcs",
     ],
     deps = [
-        ":java",
+        ":helpers",
         "@com_google_googletest//:gtest",
         "@com_google_googletest//:gtest_main",
     ],
@@ -178,7 +218,7 @@ cc_test(
     srcs = ["plugin_unittest.cc"],
     deps = [
         ":java",
-        "//:protobuf",
+        "//src/google/protobuf",
         "//src/google/protobuf/compiler:command_line_interface",
         "//src/google/protobuf/io",
         "//src/google/protobuf/io:printer",

src/google/protobuf/compiler/java/context.cc

@@ -13,7 +13,7 @@
 #include "absl/strings/str_cat.h"
 #include "absl/strings/string_view.h"
 #include "absl/strings/strip.h"
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/descriptor.h"

src/google/protobuf/compiler/java/field.cc

@@ -1,294 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-//
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file or at
-// https://developers.google.com/open-source/licenses/bsd
-
-// Author: kenton@google.com (Kenton Varda)
-//  Based on original Protocol Buffers design by
-//  Sanjay Ghemawat, Jeff Dean, and others.
-
-#include "google/protobuf/compiler/java/field.h"
-
-#include <memory>
-#include <string>
-
-#include "absl/container/flat_hash_map.h"
-#include "absl/log/absl_log.h"
-#include "absl/strings/str_cat.h"
-#include "absl/strings/substitute.h"
-#include "google/protobuf/compiler/java/context.h"
-#include "google/protobuf/compiler/java/enum_field.h"
-#include "google/protobuf/compiler/java/enum_field_lite.h"
-#include "google/protobuf/compiler/java/helpers.h"
-#include "google/protobuf/compiler/java/map_field.h"
-#include "google/protobuf/compiler/java/map_field_lite.h"
-#include "google/protobuf/compiler/java/message_field.h"
-#include "google/protobuf/compiler/java/message_field_lite.h"
-#include "google/protobuf/compiler/java/primitive_field.h"
-#include "google/protobuf/compiler/java/primitive_field_lite.h"
-#include "google/protobuf/compiler/java/string_field.h"
-#include "google/protobuf/compiler/java/string_field_lite.h"
-#include "google/protobuf/io/printer.h"
-
-
-namespace google {
-namespace protobuf {
-namespace compiler {
-namespace java {
-
-namespace {
-
-ImmutableFieldGenerator* MakeImmutableGenerator(const FieldDescriptor* field,
-                                                int messageBitIndex,
-                                                int builderBitIndex,
-                                                Context* context) {
-  if (field->is_repeated()) {
-    switch (GetJavaType(field)) {
-      case JAVATYPE_MESSAGE:
-        if (IsMapEntry(field->message_type())) {
-          return new ImmutableMapFieldGenerator(field, messageBitIndex,
-                                                builderBitIndex, context);
-        } else {
-          return new RepeatedImmutableMessageFieldGenerator(
-              field, messageBitIndex, builderBitIndex, context);
-        }
-      case JAVATYPE_ENUM:
-        return new RepeatedImmutableEnumFieldGenerator(
-            field, messageBitIndex, builderBitIndex, context);
-      case JAVATYPE_STRING:
-        return new RepeatedImmutableStringFieldGenerator(
-            field, messageBitIndex, builderBitIndex, context);
-      default:
-        return new RepeatedImmutablePrimitiveFieldGenerator(
-            field, messageBitIndex, builderBitIndex, context);
-    }
-  } else {
-    if (IsRealOneof(field)) {
-      switch (GetJavaType(field)) {
-        case JAVATYPE_MESSAGE:
-          return new ImmutableMessageOneofFieldGenerator(
-              field, messageBitIndex, builderBitIndex, context);
-        case JAVATYPE_ENUM:
-          return new ImmutableEnumOneofFieldGenerator(field, messageBitIndex,
-                                                      builderBitIndex, context);
-        case JAVATYPE_STRING:
-          return new ImmutableStringOneofFieldGenerator(
-              field, messageBitIndex, builderBitIndex, context);
-        default:
-          return new ImmutablePrimitiveOneofFieldGenerator(
-              field, messageBitIndex, builderBitIndex, context);
-      }
-    } else {
-      switch (GetJavaType(field)) {
-        case JAVATYPE_MESSAGE:
-          return new ImmutableMessageFieldGenerator(field, messageBitIndex,
-                                                    builderBitIndex, context);
-        case JAVATYPE_ENUM:
-          return new ImmutableEnumFieldGenerator(field, messageBitIndex,
-                                                 builderBitIndex, context);
-        case JAVATYPE_STRING:
-          return new ImmutableStringFieldGenerator(field, messageBitIndex,
-                                                   builderBitIndex, context);
-        default:
-          return new ImmutablePrimitiveFieldGenerator(field, messageBitIndex,
-                                                      builderBitIndex, context);
-      }
-    }
-  }
-}
-
-ImmutableFieldLiteGenerator* MakeImmutableLiteGenerator(
-    const FieldDescriptor* field, int messageBitIndex, Context* context) {
-  if (field->is_repeated()) {
-    switch (GetJavaType(field)) {
-      case JAVATYPE_MESSAGE:
-        if (IsMapEntry(field->message_type())) {
-          return new ImmutableMapFieldLiteGenerator(field, messageBitIndex,
-                                                    context);
-        } else {
-          return new RepeatedImmutableMessageFieldLiteGenerator(
-              field, messageBitIndex, context);
-        }
-      case JAVATYPE_ENUM:
-        return new RepeatedImmutableEnumFieldLiteGenerator(
-            field, messageBitIndex, context);
-      case JAVATYPE_STRING:
-        return new RepeatedImmutableStringFieldLiteGenerator(
-            field, messageBitIndex, context);
-      default:
-        return new RepeatedImmutablePrimitiveFieldLiteGenerator(
-            field, messageBitIndex, context);
-    }
-  } else {
-    if (IsRealOneof(field)) {
-      switch (GetJavaType(field)) {
-        case JAVATYPE_MESSAGE:
-          return new ImmutableMessageOneofFieldLiteGenerator(
-              field, messageBitIndex, context);
-        case JAVATYPE_ENUM:
-          return new ImmutableEnumOneofFieldLiteGenerator(
-              field, messageBitIndex, context);
-        case JAVATYPE_STRING:
-          return new ImmutableStringOneofFieldLiteGenerator(
-              field, messageBitIndex, context);
-        default:
-          return new ImmutablePrimitiveOneofFieldLiteGenerator(
-              field, messageBitIndex, context);
-      }
-    } else {
-      switch (GetJavaType(field)) {
-        case JAVATYPE_MESSAGE:
-          return new ImmutableMessageFieldLiteGenerator(field, messageBitIndex,
-                                                        context);
-        case JAVATYPE_ENUM:
-          return new ImmutableEnumFieldLiteGenerator(field, messageBitIndex,
-                                                     context);
-        case JAVATYPE_STRING:
-          return new ImmutableStringFieldLiteGenerator(field, messageBitIndex,
-                                                       context);
-        default:
-          return new ImmutablePrimitiveFieldLiteGenerator(
-              field, messageBitIndex, context);
-      }
-    }
-  }
-}
-
-
-static inline void ReportUnexpectedPackedFieldsCall(io::Printer* printer) {
-  // Reaching here indicates a bug. Cases are:
-  //   - This FieldGenerator should support packing,
-  //     but this method should be overridden.
-  //   - This FieldGenerator doesn't support packing, and this method
-  //     should never have been called.
-  ABSL_LOG(FATAL) << "GenerateBuilderParsingCodeFromPacked() "
-                  << "called on field generator that does not support packing.";
-}
-
-}  // namespace
-
-ImmutableFieldGenerator::~ImmutableFieldGenerator() {}
-
-void ImmutableFieldGenerator::GenerateBuilderParsingCodeFromPacked(
-    io::Printer* printer) const {
-  ReportUnexpectedPackedFieldsCall(printer);
-}
-
-ImmutableFieldLiteGenerator::~ImmutableFieldLiteGenerator() {}
-
-// ===================================================================
-
-template <>
-FieldGeneratorMap<ImmutableFieldGenerator>::FieldGeneratorMap(
-    const Descriptor* descriptor, Context* context)
-    : descriptor_(descriptor), field_generators_(descriptor->field_count()) {
-  // Construct all the FieldGenerators and assign them bit indices for their
-  // bit fields.
-  int messageBitIndex = 0;
-  int builderBitIndex = 0;
-  for (int i = 0; i < descriptor->field_count(); i++) {
-    ImmutableFieldGenerator* generator = MakeImmutableGenerator(
-        descriptor->field(i), messageBitIndex, builderBitIndex, context);
-    field_generators_[i].reset(generator);
-    messageBitIndex += generator->GetNumBitsForMessage();
-    builderBitIndex += generator->GetNumBitsForBuilder();
-  }
-}
-
-template <>
-FieldGeneratorMap<ImmutableFieldGenerator>::~FieldGeneratorMap() {}
-
-template <>
-FieldGeneratorMap<ImmutableFieldLiteGenerator>::FieldGeneratorMap(
-    const Descriptor* descriptor, Context* context)
-    : descriptor_(descriptor), field_generators_(descriptor->field_count()) {
-  // Construct all the FieldGenerators and assign them bit indices for their
-  // bit fields.
-  int messageBitIndex = 0;
-  for (int i = 0; i < descriptor->field_count(); i++) {
-    ImmutableFieldLiteGenerator* generator = MakeImmutableLiteGenerator(
-        descriptor->field(i), messageBitIndex, context);
-    field_generators_[i].reset(generator);
-    messageBitIndex += generator->GetNumBitsForMessage();
-  }
-}
-
-template <>
-FieldGeneratorMap<ImmutableFieldLiteGenerator>::~FieldGeneratorMap() {}
-
-
-void SetCommonFieldVariables(
-    const FieldDescriptor* descriptor, const FieldGeneratorInfo* info,
-    absl::flat_hash_map<absl::string_view, std::string>* variables) {
-  (*variables)["field_name"] = descriptor->name();
-  (*variables)["name"] = info->name;
-  (*variables)["classname"] = descriptor->containing_type()->name();
-  (*variables)["capitalized_name"] = info->capitalized_name;
-  (*variables)["disambiguated_reason"] = info->disambiguated_reason;
-  (*variables)["constant_name"] = FieldConstantName(descriptor);
-  (*variables)["number"] = absl::StrCat(descriptor->number());
-  (*variables)["kt_dsl_builder"] = "_builder";
-  // These variables are placeholders to pick out the beginning and ends of
-  // identifiers for annotations (when doing so with existing variables would
-  // be ambiguous or impossible). They should never be set to anything but the
-  // empty string.
-  (*variables)["{"] = "";
-  (*variables)["}"] = "";
-  (*variables)["kt_name"] = IsForbiddenKotlin(info->name)
-                                ? absl::StrCat(info->name, "_")
-                                : info->name;
-  (*variables)["kt_capitalized_name"] =
-      IsForbiddenKotlin(info->name) ? absl::StrCat(info->capitalized_name, "_")
-                                    : info->capitalized_name;
-  if (!descriptor->is_repeated()) {
-    (*variables)["annotation_field_type"] =
-        std::string(FieldTypeName(descriptor->type()));
-  } else if (GetJavaType(descriptor) == JAVATYPE_MESSAGE &&
-             IsMapEntry(descriptor->message_type())) {
-    (*variables)["annotation_field_type"] =
-        absl::StrCat(FieldTypeName(descriptor->type()), "MAP");
-  } else {
-    (*variables)["annotation_field_type"] =
-        absl::StrCat(FieldTypeName(descriptor->type()), "_LIST");
-    if (descriptor->is_packed()) {
-      variables->insert(
-          {"annotation_field_type",
-           absl::StrCat(FieldTypeName(descriptor->type()), "_LIST_PACKED")});
-    }
-  }
-}
-
-void SetCommonOneofVariables(
-    const FieldDescriptor* descriptor, const OneofGeneratorInfo* info,
-    absl::flat_hash_map<absl::string_view, std::string>* variables) {
-  (*variables)["oneof_name"] = info->name;
-  (*variables)["oneof_capitalized_name"] = info->capitalized_name;
-  (*variables)["oneof_index"] =
-      absl::StrCat(descriptor->containing_oneof()->index());
-  (*variables)["oneof_stored_type"] = GetOneofStoredType(descriptor);
-  (*variables)["set_oneof_case_message"] =
-      absl::StrCat(info->name, "Case_ = ", descriptor->number());
-  (*variables)["clear_oneof_case_message"] =
-      absl::StrCat(info->name, "Case_ = 0");
-  (*variables)["has_oneof_case_message"] =
-      absl::StrCat(info->name, "Case_ == ", descriptor->number());
-}
-
-void PrintExtraFieldInfo(
-    const absl::flat_hash_map<absl::string_view, std::string>& variables,
-    io::Printer* printer) {
-  auto it = variables.find("disambiguated_reason");
-  if (it != variables.end() && !it->second.empty()) {
-    printer->Print(
-        variables,
-        "// An alternative name is used for field \"$field_name$\" because:\n"
-        "//     $disambiguated_reason$\n");
-  }
-}
-
-}  // namespace java
-}  // namespace compiler
-}  // namespace protobuf
-}  // namespace google

src/google/protobuf/compiler/java/field.h

@@ -1,169 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-//
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file or at
-// https://developers.google.com/open-source/licenses/bsd
-
-// Author: kenton@google.com (Kenton Varda)
-//  Based on original Protocol Buffers design by
-//  Sanjay Ghemawat, Jeff Dean, and others.
-
-#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_FIELD_H__
-#define GOOGLE_PROTOBUF_COMPILER_JAVA_FIELD_H__
-
-#include <cstdint>
-#include <memory>
-#include <string>
-
-#include "absl/container/flat_hash_map.h"
-#include "absl/log/absl_check.h"
-#include "google/protobuf/descriptor.h"
-#include "google/protobuf/port.h"
-
-namespace google {
-namespace protobuf {
-namespace compiler {
-namespace java {
-class Context;            // context.h
-class ClassNameResolver;  // name_resolver.h
-}  // namespace java
-}  // namespace compiler
-namespace io {
-class Printer;  // printer.h
-}
-}  // namespace protobuf
-}  // namespace google
-
-namespace google {
-namespace protobuf {
-namespace compiler {
-namespace java {
-
-class ImmutableFieldGenerator {
- public:
-  ImmutableFieldGenerator() {}
-  ImmutableFieldGenerator(const ImmutableFieldGenerator&) = delete;
-  ImmutableFieldGenerator& operator=(const ImmutableFieldGenerator&) = delete;
-  virtual ~ImmutableFieldGenerator();
-
-  virtual int GetMessageBitIndex() const = 0;
-  virtual int GetBuilderBitIndex() const = 0;
-  virtual int GetNumBitsForMessage() const = 0;
-  virtual int GetNumBitsForBuilder() const = 0;
-  virtual void GenerateInterfaceMembers(io::Printer* printer) const = 0;
-  virtual void GenerateMembers(io::Printer* printer) const = 0;
-  virtual void GenerateBuilderMembers(io::Printer* printer) const = 0;
-  virtual void GenerateInitializationCode(io::Printer* printer) const = 0;
-  virtual void GenerateBuilderClearCode(io::Printer* printer) const = 0;
-  virtual void GenerateMergingCode(io::Printer* printer) const = 0;
-  virtual void GenerateBuildingCode(io::Printer* printer) const = 0;
-  virtual void GenerateBuilderParsingCode(io::Printer* printer) const = 0;
-  virtual void GenerateBuilderParsingCodeFromPacked(io::Printer* printer) const;
-  virtual void GenerateSerializationCode(io::Printer* printer) const = 0;
-  virtual void GenerateSerializedSizeCode(io::Printer* printer) const = 0;
-  virtual void GenerateFieldBuilderInitializationCode(
-      io::Printer* printer) const = 0;
-  virtual void GenerateKotlinDslMembers(io::Printer* printer) const = 0;
-
-  virtual void GenerateEqualsCode(io::Printer* printer) const = 0;
-  virtual void GenerateHashCode(io::Printer* printer) const = 0;
-
-  virtual std::string GetBoxedType() const = 0;
-};
-
-class ImmutableFieldLiteGenerator {
- public:
-  ImmutableFieldLiteGenerator() {}
-  ImmutableFieldLiteGenerator(const ImmutableFieldLiteGenerator&) = delete;
-  ImmutableFieldLiteGenerator& operator=(const ImmutableFieldLiteGenerator&) =
-      delete;
-  virtual ~ImmutableFieldLiteGenerator();
-
-  virtual int GetNumBitsForMessage() const = 0;
-  virtual void GenerateInterfaceMembers(io::Printer* printer) const = 0;
-  virtual void GenerateMembers(io::Printer* printer) const = 0;
-  virtual void GenerateBuilderMembers(io::Printer* printer) const = 0;
-  virtual void GenerateInitializationCode(io::Printer* printer) const = 0;
-  virtual void GenerateFieldInfo(io::Printer* printer,
-                                 std::vector<uint16_t>* output) const = 0;
-  virtual void GenerateKotlinDslMembers(io::Printer* printer) const = 0;
-
-  virtual std::string GetBoxedType() const = 0;
-};
-
-
-// Convenience class which constructs FieldGenerators for a Descriptor.
-template <typename FieldGeneratorType>
-class FieldGeneratorMap {
- public:
-  explicit FieldGeneratorMap(const Descriptor* descriptor, Context* context);
-  FieldGeneratorMap(const FieldGeneratorMap&) = delete;
-  FieldGeneratorMap& operator=(const FieldGeneratorMap&) = delete;
-  ~FieldGeneratorMap();
-
-  const FieldGeneratorType& get(const FieldDescriptor* field) const;
-
- private:
-  const Descriptor* descriptor_;
-  std::vector<std::unique_ptr<FieldGeneratorType>> field_generators_;
-};
-
-template <typename FieldGeneratorType>
-inline const FieldGeneratorType& FieldGeneratorMap<FieldGeneratorType>::get(
-    const FieldDescriptor* field) const {
-  ABSL_CHECK_EQ(field->containing_type(), descriptor_);
-  return *field_generators_[field->index()];
-}
-
-// Instantiate template for mutable and immutable maps.
-template <>
-FieldGeneratorMap<ImmutableFieldGenerator>::FieldGeneratorMap(
-    const Descriptor* descriptor, Context* context);
-
-template <>
-FieldGeneratorMap<ImmutableFieldGenerator>::~FieldGeneratorMap();
-
-
-template <>
-FieldGeneratorMap<ImmutableFieldLiteGenerator>::FieldGeneratorMap(
-    const Descriptor* descriptor, Context* context);
-
-template <>
-FieldGeneratorMap<ImmutableFieldLiteGenerator>::~FieldGeneratorMap();
-
-
-// Field information used in FieldGenerators.
-struct FieldGeneratorInfo {
-  std::string name;
-  std::string capitalized_name;
-  std::string disambiguated_reason;
-};
-
-// Oneof information used in OneofFieldGenerators.
-struct OneofGeneratorInfo {
-  std::string name;
-  std::string capitalized_name;
-};
-
-// Set some common variables used in variable FieldGenerators.
-void SetCommonFieldVariables(
-    const FieldDescriptor* descriptor, const FieldGeneratorInfo* info,
-    absl::flat_hash_map<absl::string_view, std::string>* variables);
-
-// Set some common oneof variables used in OneofFieldGenerators.
-void SetCommonOneofVariables(
-    const FieldDescriptor* descriptor, const OneofGeneratorInfo* info,
-    absl::flat_hash_map<absl::string_view, std::string>* variables);
-
-// Print useful comments before a field's accessors.
-void PrintExtraFieldInfo(
-    const absl::flat_hash_map<absl::string_view, std::string>& variables,
-    io::Printer* printer);
-
-}  // namespace java
-}  // namespace compiler
-}  // namespace protobuf
-}  // namespace google
-
-#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_FIELD_H__

src/google/protobuf/compiler/java/field_common.cc

@@ -0,0 +1,85 @@
+#include "google/protobuf/compiler/java/field_common.h"
+
+#include <string>
+
+#include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/descriptor.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+void SetCommonFieldVariables(
+    const FieldDescriptor* descriptor, const FieldGeneratorInfo* info,
+    absl::flat_hash_map<absl::string_view, std::string>* variables) {
+  (*variables)["field_name"] = descriptor->name();
+  (*variables)["name"] = info->name;
+  (*variables)["classname"] = descriptor->containing_type()->name();
+  (*variables)["capitalized_name"] = info->capitalized_name;
+  (*variables)["disambiguated_reason"] = info->disambiguated_reason;
+  (*variables)["constant_name"] = FieldConstantName(descriptor);
+  (*variables)["number"] = absl::StrCat(descriptor->number());
+  (*variables)["kt_dsl_builder"] = "_builder";
+  // These variables are placeholders to pick out the beginning and ends of
+  // identifiers for annotations (when doing so with existing variables would
+  // be ambiguous or impossible). They should never be set to anything but the
+  // empty string.
+  (*variables)["{"] = "";
+  (*variables)["}"] = "";
+  (*variables)["kt_name"] = IsForbiddenKotlin(info->name)
+                                ? absl::StrCat(info->name, "_")
+                                : info->name;
+  (*variables)["kt_capitalized_name"] =
+      IsForbiddenKotlin(info->name) ? absl::StrCat(info->capitalized_name, "_")
+                                    : info->capitalized_name;
+  if (!descriptor->is_repeated()) {
+    (*variables)["annotation_field_type"] =
+        std::string(FieldTypeName(descriptor->type()));
+  } else if (GetJavaType(descriptor) == JAVATYPE_MESSAGE &&
+             IsMapEntry(descriptor->message_type())) {
+    (*variables)["annotation_field_type"] =
+        absl::StrCat(FieldTypeName(descriptor->type()), "MAP");
+  } else {
+    (*variables)["annotation_field_type"] =
+        absl::StrCat(FieldTypeName(descriptor->type()), "_LIST");
+    if (descriptor->is_packed()) {
+      variables->insert(
+          {"annotation_field_type",
+           absl::StrCat(FieldTypeName(descriptor->type()), "_LIST_PACKED")});
+    }
+  }
+}
+
+void SetCommonOneofVariables(
+    const FieldDescriptor* descriptor, const OneofGeneratorInfo* info,
+    absl::flat_hash_map<absl::string_view, std::string>* variables) {
+  (*variables)["oneof_name"] = info->name;
+  (*variables)["oneof_capitalized_name"] = info->capitalized_name;
+  (*variables)["oneof_index"] =
+      absl::StrCat(descriptor->containing_oneof()->index());
+  (*variables)["oneof_stored_type"] = GetOneofStoredType(descriptor);
+  (*variables)["set_oneof_case_message"] =
+      absl::StrCat(info->name, "Case_ = ", descriptor->number());
+  (*variables)["clear_oneof_case_message"] =
+      absl::StrCat(info->name, "Case_ = 0");
+  (*variables)["has_oneof_case_message"] =
+      absl::StrCat(info->name, "Case_ == ", descriptor->number());
+}
+
+void PrintExtraFieldInfo(
+    const absl::flat_hash_map<absl::string_view, std::string>& variables,
+    io::Printer* printer) {
+  auto it = variables.find("disambiguated_reason");
+  if (it != variables.end() && !it->second.empty()) {
+    printer->Print(
+        variables,
+        "// An alternative name is used for field \"$field_name$\" because:\n"
+        "//     $disambiguated_reason$\n");
+  }
+}
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google

src/google/protobuf/compiler/java/field_common.h

@@ -0,0 +1,44 @@
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_FIELD_COMMON_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_FIELD_COMMON_H__
+
+#include "google/protobuf/descriptor.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+// Field information used in FieldGenerators.
+struct FieldGeneratorInfo {
+  std::string name;
+  std::string capitalized_name;
+  std::string disambiguated_reason;
+};
+
+// Oneof information used in OneofFieldGenerators.
+struct OneofGeneratorInfo {
+  std::string name;
+  std::string capitalized_name;
+};
+
+// Set some common variables used in variable FieldGenerators.
+void SetCommonFieldVariables(
+    const FieldDescriptor* descriptor, const FieldGeneratorInfo* info,
+    absl::flat_hash_map<absl::string_view, std::string>* variables);
+
+// Set some common oneof variables used in OneofFieldGenerators.
+void SetCommonOneofVariables(
+    const FieldDescriptor* descriptor, const OneofGeneratorInfo* info,
+    absl::flat_hash_map<absl::string_view, std::string>* variables);
+
+// Print useful comments before a field's accessors.
+void PrintExtraFieldInfo(
+    const absl::flat_hash_map<absl::string_view, std::string>& variables,
+    io::Printer* printer);
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_FIELD_COMMON_H__

src/google/protobuf/compiler/java/file.cc

@@ -12,22 +12,23 @@
 #include "google/protobuf/compiler/java/file.h"
 
 #include <memory>
+#include <string>
 #include <vector>
 
 #include "absl/container/btree_set.h"
+#include "absl/log/absl_check.h"
 #include "absl/log/absl_log.h"
 #include "absl/strings/str_cat.h"
 #include "absl/strings/string_view.h"
 #include "google/protobuf/compiler/code_generator.h"
 #include "google/protobuf/compiler/java/context.h"
-#include "google/protobuf/compiler/java/enum.h"
+#include "google/protobuf/compiler/java/generator_common.h"
-#include "google/protobuf/compiler/java/enum_lite.h"
-#include "google/protobuf/compiler/java/extension.h"
 #include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/compiler/java/helpers.h"
-#include "google/protobuf/compiler/java/message.h"
+#include "google/protobuf/compiler/java/immutable/generator_factory.h"
+#include "google/protobuf/compiler/java/lite/generator_factory.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
-#include "google/protobuf/compiler/java/service.h"
+#include "google/protobuf/compiler/java/options.h"
 #include "google/protobuf/compiler/java/shared_code_generator.h"
 #include "google/protobuf/compiler/retention.h"
 #include "google/protobuf/compiler/versions.h"
@@ -36,6 +37,7 @@
 #include "google/protobuf/io/printer.h"
 #include "google/protobuf/io/zero_copy_stream.h"
 
+
 // Must be last.
 #include "google/protobuf/port_def.inc"
 
@@ -165,6 +167,18 @@ void MaybeRestartJavaMethod(io::Printer* printer, int* bytecode_estimate,
     *bytecode_estimate = 0;
   }
 }
+
+std::unique_ptr<GeneratorFactory> CreateGeneratorFactory(
+    const FileDescriptor* file, const Options& options, Context* context,
+    bool immutable_api) {
+  ABSL_CHECK(immutable_api)
+      << "Open source release does not support the mutable API";
+  if (HasDescriptorMethods(file, context->EnforceLite())) {
+    return MakeImmutableGeneratorFactory(context);
+  } else {
+    return MakeImmutableLiteGeneratorFactory(context);
+  }
+}
 }  // namespace
 
 FileGenerator::FileGenerator(const FileDescriptor* file, const Options& options,
@@ -174,18 +188,19 @@ FileGenerator::FileGenerator(const FileDescriptor* file, const Options& options,
       message_generators_(file->message_type_count()),
       extension_generators_(file->extension_count()),
       context_(new Context(file, options)),
+      generator_factory_(
+          CreateGeneratorFactory(file, options, context_.get(), immutable_api)),
       name_resolver_(context_->GetNameResolver()),
       options_(options),
       immutable_api_(immutable_api) {
   classname_ = name_resolver_->GetFileClassName(file, immutable_api);
-    generator_factory_.reset(new ImmutableGeneratorFactory(context_.get()));
   for (int i = 0; i < file_->message_type_count(); ++i) {
-    message_generators_[i].reset(
+    message_generators_[i] =
-        generator_factory_->NewMessageGenerator(file_->message_type(i)));
+        generator_factory_->NewMessageGenerator(file_->message_type(i));
   }
   for (int i = 0; i < file_->extension_count(); ++i) {
-    extension_generators_[i].reset(
+    extension_generators_[i] =
-        generator_factory_->NewExtensionGenerator(file_->extension(i)));
+        generator_factory_->NewExtensionGenerator(file_->extension(i));
   }
 }
 
@@ -322,13 +337,8 @@ void FileGenerator::Generate(io::Printer* printer) {
 
   if (!MultipleJavaFiles(file_, immutable_api_)) {
     for (int i = 0; i < file_->enum_type_count(); i++) {
-      if (HasDescriptorMethods(file_, context_->EnforceLite())) {
+      generator_factory_->NewEnumGenerator(file_->enum_type(i))
-        EnumGenerator(file_->enum_type(i), immutable_api_, context_.get())
+          ->Generate(printer);
-            .Generate(printer);
-      } else {
-        EnumLiteGenerator(file_->enum_type(i), immutable_api_, context_.get())
-            .Generate(printer);
-      }
     }
     for (int i = 0; i < file_->message_type_count(); i++) {
       message_generators_[i]->GenerateInterface(printer);
@@ -556,21 +566,12 @@ void FileGenerator::GenerateSiblings(
     std::vector<std::string>* annotation_list) {
   if (MultipleJavaFiles(file_, immutable_api_)) {
     for (int i = 0; i < file_->enum_type_count(); i++) {
-      if (HasDescriptorMethods(file_, context_->EnforceLite())) {
+      std::unique_ptr<EnumGenerator> generator(
-        EnumGenerator generator(file_->enum_type(i), immutable_api_,
+          generator_factory_->NewEnumGenerator(file_->enum_type(i)));
-                                context_.get());
+      GenerateSibling<EnumGenerator>(
-        GenerateSibling<EnumGenerator>(
+          package_dir, java_package_, file_->enum_type(i), context, file_list,
-            package_dir, java_package_, file_->enum_type(i), context, file_list,
+          options_.annotate_code, annotation_list, "", generator.get(),
-            options_.annotate_code, annotation_list, "", &generator,
+          options_.opensource_runtime, &EnumGenerator::Generate);
-            options_.opensource_runtime, &EnumGenerator::Generate);
-      } else {
-        EnumLiteGenerator generator(file_->enum_type(i), immutable_api_,
-                                    context_.get());
-        GenerateSibling<EnumLiteGenerator>(
-            package_dir, java_package_, file_->enum_type(i), context, file_list,
-            options_.annotate_code, annotation_list, "", &generator,
-            options_.opensource_runtime, &EnumLiteGenerator::Generate);
-      }
     }
     for (int i = 0; i < file_->message_type_count(); i++) {
       if (immutable_api_) {

src/google/protobuf/compiler/java/file.h

@@ -88,8 +88,8 @@ class FileGenerator {
 
   std::vector<std::unique_ptr<MessageGenerator>> message_generators_;
   std::vector<std::unique_ptr<ExtensionGenerator>> extension_generators_;
-  std::unique_ptr<GeneratorFactory> generator_factory_;
   std::unique_ptr<Context> context_;
+  std::unique_ptr<GeneratorFactory> generator_factory_;
   ClassNameResolver* name_resolver_;
   const Options options_;
   bool immutable_api_;

src/google/protobuf/compiler/java/generator_common.h

@@ -0,0 +1,89 @@
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_SERVICE_COMMON_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_SERVICE_COMMON_H__
+
+#include <cstddef>
+#include <memory>
+#include <vector>
+
+#include "absl/log/absl_check.h"
+#include "absl/log/absl_log.h"
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/name_resolver.h"
+#include "google/protobuf/descriptor.h"
+#include "google/protobuf/io/printer.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+static const int kMaxStaticSize = 1 << 15;  // aka 32k
+
+class FieldGenerator {
+ public:
+  virtual ~FieldGenerator() = default;
+  virtual void GenerateSerializationCode(io::Printer* printer) const = 0;
+};
+
+// Convenience class which constructs FieldGenerators for a Descriptor.
+template <typename FieldGeneratorType>
+class FieldGeneratorMap {
+ public:
+  explicit FieldGeneratorMap(const Descriptor* descriptor)
+      : descriptor_(descriptor) {
+    field_generators_.reserve(static_cast<size_t>(descriptor->field_count()));
+  }
+
+  ~FieldGeneratorMap() {
+    for (const auto* g : field_generators_) {
+      delete g;
+    }
+  }
+
+  FieldGeneratorMap(FieldGeneratorMap&&) = default;
+  FieldGeneratorMap& operator=(FieldGeneratorMap&&) = default;
+
+  FieldGeneratorMap(const FieldGeneratorMap&) = delete;
+  FieldGeneratorMap& operator=(const FieldGeneratorMap&) = delete;
+
+  void Add(const FieldDescriptor* field,
+           std::unique_ptr<FieldGeneratorType> field_generator) {
+    ABSL_CHECK_EQ(field->containing_type(), descriptor_);
+    field_generators_.push_back(field_generator.release());
+  }
+
+  const FieldGeneratorType& get(const FieldDescriptor* field) const {
+    ABSL_CHECK_EQ(field->containing_type(), descriptor_);
+    return *field_generators_[static_cast<size_t>(field->index())];
+  }
+
+  std::vector<const FieldGenerator*> field_generators() const {
+    std::vector<const FieldGenerator*> field_generators;
+    field_generators.reserve(field_generators_.size());
+    for (const auto* g : field_generators_) {
+      field_generators.push_back(g);
+    }
+    return field_generators;
+  }
+
+ private:
+  const Descriptor* descriptor_;
+  std::vector<const FieldGeneratorType*> field_generators_;
+};
+
+inline void ReportUnexpectedPackedFieldsCall() {
+  // Reaching here indicates a bug. Cases are:
+  //   - This FieldGenerator should support packing,
+  //     but this method should be overridden.
+  //   - This FieldGenerator doesn't support packing, and this method
+  //     should never have been called.
+  ABSL_LOG(FATAL) << "GenerateBuilderParsingCodeFromPacked() "
+                  << "called on field generator that does not support packing.";
+}
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_SERVICE_COMMON_H__

src/google/protobuf/compiler/java/generator_factory.cc

@@ -1,63 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-//
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file or at
-// https://developers.google.com/open-source/licenses/bsd
-
-// Author: liujisi@google.com (Pherl Liu)
-
-#include "google/protobuf/compiler/java/generator_factory.h"
-
-#include "google/protobuf/compiler/java/context.h"
-#include "google/protobuf/compiler/java/enum_field.h"
-#include "google/protobuf/compiler/java/extension.h"
-#include "google/protobuf/compiler/java/extension_lite.h"
-#include "google/protobuf/compiler/java/field.h"
-#include "google/protobuf/compiler/java/helpers.h"
-#include "google/protobuf/compiler/java/message.h"
-#include "google/protobuf/compiler/java/message_lite.h"
-#include "google/protobuf/compiler/java/service.h"
-
-namespace google {
-namespace protobuf {
-namespace compiler {
-namespace java {
-
-GeneratorFactory::GeneratorFactory() {}
-GeneratorFactory::~GeneratorFactory() {}
-
-// ===================================================================
-
-ImmutableGeneratorFactory::ImmutableGeneratorFactory(Context* context)
-    : context_(context) {}
-ImmutableGeneratorFactory::~ImmutableGeneratorFactory() {}
-
-MessageGenerator* ImmutableGeneratorFactory::NewMessageGenerator(
-    const Descriptor* descriptor) const {
-  if (HasDescriptorMethods(descriptor, context_->EnforceLite())) {
-    return new ImmutableMessageGenerator(descriptor, context_);
-  } else {
-    return new ImmutableMessageLiteGenerator(descriptor, context_);
-  }
-}
-
-ExtensionGenerator* ImmutableGeneratorFactory::NewExtensionGenerator(
-    const FieldDescriptor* descriptor) const {
-  if (HasDescriptorMethods(descriptor->file(), context_->EnforceLite())) {
-    return new ImmutableExtensionGenerator(descriptor, context_);
-  } else {
-    return new ImmutableExtensionLiteGenerator(descriptor, context_);
-  }
-}
-
-ServiceGenerator* ImmutableGeneratorFactory::NewServiceGenerator(
-    const ServiceDescriptor* descriptor) const {
-  return new ImmutableServiceGenerator(descriptor, context_);
-}
-
-
-}  // namespace java
-}  // namespace compiler
-}  // namespace protobuf
-}  // namespace google

src/google/protobuf/compiler/java/generator_factory.h

@@ -10,68 +10,123 @@
 #ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_GENERATOR_FACTORY_H__
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_GENERATOR_FACTORY_H__
 
-#include "google/protobuf/port.h"
+#include <memory>
+#include <string>
 
-namespace google {
+#include "absl/container/btree_map.h"
-namespace protobuf {
+#include "absl/container/flat_hash_map.h"
-class FieldDescriptor;    // descriptor.h
+#include "absl/strings/string_view.h"
-class Descriptor;         // descriptor.h
+#include "google/protobuf/compiler/java/context.h"
-class ServiceDescriptor;  // descriptor.h
+#include "google/protobuf/descriptor.h"
-namespace compiler {
-namespace java {
-class MessageGenerator;    // message.h
-class ExtensionGenerator;  // extension.h
-class ServiceGenerator;    // service.h
-class Context;             // context.h
-}  // namespace java
-}  // namespace compiler
-}  // namespace protobuf
-}  // namespace google
 
 namespace google {
 namespace protobuf {
 namespace compiler {
 namespace java {
 
-class GeneratorFactory {
+class MessageGenerator {
  public:
-  GeneratorFactory();
+  explicit MessageGenerator(const Descriptor* descriptor);
-  GeneratorFactory(const GeneratorFactory&) = delete;
+  MessageGenerator(const MessageGenerator&) = delete;
-  GeneratorFactory& operator=(const GeneratorFactory&) = delete;
+  MessageGenerator& operator=(const MessageGenerator&) = delete;
-  virtual ~GeneratorFactory();
+  virtual ~MessageGenerator();
+
+  // All static variables have to be declared at the top-level of the file
+  // so that we can control initialization order, which is important for
+  // DescriptorProto bootstrapping to work.
+  virtual void GenerateStaticVariables(io::Printer* printer,
+                                       int* bytecode_estimate) = 0;
+
+  // Output code which initializes the static variables generated by
+  // GenerateStaticVariables(). Returns an estimate of bytecode size.
+  virtual int GenerateStaticVariableInitializers(io::Printer* printer) = 0;
+
+  // Generate the class itself.
+  virtual void Generate(io::Printer* printer) = 0;
+
+  // Generates the base interface that both the class and its builder
+  // implement
+  virtual void GenerateInterface(io::Printer* printer) = 0;
+
+  // Generate code to register all contained extensions with an
+  // ExtensionRegistry.
+  virtual void GenerateExtensionRegistrationCode(io::Printer* printer) = 0;
+  virtual void GenerateKotlinDsl(io::Printer* printer) const = 0;
+  virtual void GenerateKotlinMembers(io::Printer* printer) const = 0;
+  virtual void GenerateTopLevelKotlinMembers(io::Printer* printer) const = 0;
+
+ protected:
+  const Descriptor* descriptor_;
+  absl::btree_map<int, const OneofDescriptor*> oneofs_;
+};
 
-  virtual MessageGenerator* NewMessageGenerator(
+class EnumGenerator {
-      const Descriptor* descriptor) const = 0;
+ public:
+  virtual ~EnumGenerator() = default;
+  virtual void Generate(io::Printer* printer) = 0;
+};
 
-  virtual ExtensionGenerator* NewExtensionGenerator(
+// Generates code for an extension, which may be within the scope of some
-      const FieldDescriptor* descriptor) const = 0;
+// message or may be at file scope.  This is much simpler than FieldGenerator
+// since extensions are just simple identifiers with interesting types.
+class ExtensionGenerator {
+ public:
+  virtual ~ExtensionGenerator() = default;
 
-  virtual ServiceGenerator* NewServiceGenerator(
+  virtual void Generate(io::Printer* printer) = 0;
-      const ServiceDescriptor* descriptor) const = 0;
+
+  // Returns an estimate of the number of bytes the printed code will compile
+  // to
+  virtual int GenerateNonNestedInitializationCode(io::Printer* printer) = 0;
+
+  // Returns an estimate of the number of bytes the printed code will compile
+  // to
+  virtual int GenerateRegistrationCode(io::Printer* printer) = 0;
+
+ protected:
+  static void InitTemplateVars(
+      const FieldDescriptor* descriptor, const std::string& scope,
+      bool immutable, ClassNameResolver* name_resolver,
+      absl::flat_hash_map<absl::string_view, std::string>* vars_pointer,
+      Context* context);
 };
 
-// Factory that creates generators for immutable-default messages.
+class ServiceGenerator {
-class ImmutableGeneratorFactory : public GeneratorFactory {
  public:
-  ImmutableGeneratorFactory(Context* context);
+  explicit ServiceGenerator(const ServiceDescriptor* descriptor)
-  ImmutableGeneratorFactory(const ImmutableGeneratorFactory&) = delete;
+      : descriptor_(descriptor) {}
-  ImmutableGeneratorFactory& operator=(const ImmutableGeneratorFactory&) =
+  virtual ~ServiceGenerator() = default;
-      delete;
-  ~ImmutableGeneratorFactory() override;
 
-  MessageGenerator* NewMessageGenerator(
+  ServiceGenerator(const ServiceGenerator&) = delete;
-      const Descriptor* descriptor) const override;
+  ServiceGenerator& operator=(const ServiceGenerator&) = delete;
 
-  ExtensionGenerator* NewExtensionGenerator(
+  virtual void Generate(io::Printer* printer) = 0;
-      const FieldDescriptor* descriptor) const override;
 
-  ServiceGenerator* NewServiceGenerator(
+  enum RequestOrResponse { REQUEST, RESPONSE };
-      const ServiceDescriptor* descriptor) const override;
+  enum IsAbstract { IS_ABSTRACT, IS_CONCRETE };
 
- private:
+ protected:
-  Context* context_;
+  const ServiceDescriptor* descriptor_;
 };
 
+// An interface to create generators for a given descriptor.  This interface
+// is implemented for every variant of the Java API (Mutable, Immutable, Lite).
+class GeneratorFactory {
+ public:
+  virtual ~GeneratorFactory() = default;
+
+  virtual std::unique_ptr<MessageGenerator> NewMessageGenerator(
+      const Descriptor* descriptor) const = 0;
+
+  virtual std::unique_ptr<EnumGenerator> NewEnumGenerator(
+      const EnumDescriptor* descriptor) const = 0;
+
+  virtual std::unique_ptr<ExtensionGenerator> NewExtensionGenerator(
+      const FieldDescriptor* descriptor) const = 0;
+
+  virtual std::unique_ptr<ServiceGenerator> NewServiceGenerator(
+      const ServiceDescriptor* descriptor) const = 0;
+};
 
 }  // namespace java
 }  // namespace compiler

src/google/protobuf/compiler/java/helpers.cc

@@ -878,86 +878,6 @@ void WriteUInt32ToUtf16CharSequence(uint32_t number,
   output->push_back(static_cast<uint16_t>(number));
 }
 
-int GetExperimentalJavaFieldTypeForSingular(const FieldDescriptor* field) {
-  // j/c/g/protobuf/FieldType.java lists field types in a slightly different
-  // order from FieldDescriptor::Type so we can't do a simple cast.
-  //
-  // TODO: Make j/c/g/protobuf/FieldType.java follow the same order.
-  int result = field->type();
-  if (result == FieldDescriptor::TYPE_GROUP) {
-    return 17;
-  } else if (result < FieldDescriptor::TYPE_GROUP) {
-    return result - 1;
-  } else {
-    return result - 2;
-  }
-}
-
-int GetExperimentalJavaFieldTypeForRepeated(const FieldDescriptor* field) {
-  if (field->type() == FieldDescriptor::TYPE_GROUP) {
-    return 49;
-  } else {
-    return GetExperimentalJavaFieldTypeForSingular(field) + 18;
-  }
-}
-
-int GetExperimentalJavaFieldTypeForPacked(const FieldDescriptor* field) {
-  int result = field->type();
-  if (result < FieldDescriptor::TYPE_STRING) {
-    return result + 34;
-  } else if (result > FieldDescriptor::TYPE_BYTES) {
-    return result + 30;
-  } else {
-    ABSL_LOG(FATAL) << field->full_name() << " can't be packed.";
-    return 0;
-  }
-}
-
-int GetExperimentalJavaFieldType(const FieldDescriptor* field) {
-  static const int kMapFieldType = 50;
-  static const int kOneofFieldTypeOffset = 51;
-
-  static const int kRequiredBit = 0x100;
-  static const int kUtf8CheckBit = 0x200;
-  static const int kCheckInitialized = 0x400;
-  static const int kLegacyEnumIsClosedBit = 0x800;
-  static const int kHasHasBit = 0x1000;
-  int extra_bits = field->is_required() ? kRequiredBit : 0;
-  if (field->type() == FieldDescriptor::TYPE_STRING && CheckUtf8(field)) {
-    extra_bits |= kUtf8CheckBit;
-  }
-  if (field->is_required() || (GetJavaType(field) == JAVATYPE_MESSAGE &&
-                               HasRequiredFields(field->message_type()))) {
-    extra_bits |= kCheckInitialized;
-  }
-  if (HasHasbit(field)) {
-    extra_bits |= kHasHasBit;
-  }
-  if (GetJavaType(field) == JAVATYPE_ENUM && !SupportUnknownEnumValue(field)) {
-    extra_bits |= kLegacyEnumIsClosedBit;
-  }
-
-  if (field->is_map()) {
-    if (!SupportUnknownEnumValue(MapValueField(field))) {
-      const FieldDescriptor* value = field->message_type()->map_value();
-      if (GetJavaType(value) == JAVATYPE_ENUM) {
-        extra_bits |= kLegacyEnumIsClosedBit;
-      }
-    }
-    return kMapFieldType | extra_bits;
-  } else if (field->is_packed()) {
-    return GetExperimentalJavaFieldTypeForPacked(field) | extra_bits;
-  } else if (field->is_repeated()) {
-    return GetExperimentalJavaFieldTypeForRepeated(field) | extra_bits;
-  } else if (IsRealOneof(field)) {
-    return (GetExperimentalJavaFieldTypeForSingular(field) +
-            kOneofFieldTypeOffset) |
-           extra_bits;
-  } else {
-    return GetExperimentalJavaFieldTypeForSingular(field) | extra_bits;
-  }
-}
-
 // Escape a UTF-16 character to be embedded in a Java string.
 void EscapeUtf16ToString(uint16_t code, std::string* output) {
   if (code == '\t') {

src/google/protobuf/compiler/java/helpers.h

@@ -16,8 +16,6 @@
 #include <string>
 
 #include "absl/strings/string_view.h"
-#include "google/protobuf/compiler/java/generator.h"
-#include "google/protobuf/compiler/java/java_features.pb.h"
 #include "google/protobuf/compiler/java/names.h"
 #include "google/protobuf/compiler/java/options.h"
 #include "google/protobuf/descriptor.h"
@@ -344,18 +342,6 @@ inline bool HasHasbit(const FieldDescriptor* descriptor) {
   return internal::cpp::HasHasbit(descriptor);
 }
 
-// Whether unknown enum values are kept (i.e., not stored in UnknownFieldSet
-// but in the message and can be queried using additional getters that return
-// ints.
-inline bool SupportUnknownEnumValue(const FieldDescriptor* field) {
-  if (JavaGenerator::GetResolvedSourceFeatures(*field)
-          .GetExtension(pb::java)
-          .legacy_closed_enum()) {
-    return false;
-  }
-  return field->enum_type() != nullptr && !field->enum_type()->is_closed();
-}
-
 // Check whether a message has repeated fields.
 bool HasRepeatedFields(const Descriptor* descriptor);
 
@@ -375,18 +361,6 @@ inline bool IsWrappersProtoFile(const FileDescriptor* descriptor) {
   return descriptor->name() == "google/protobuf/wrappers.proto";
 }
 
-inline bool CheckUtf8(const FieldDescriptor* descriptor) {
-  if (JavaGenerator::GetResolvedSourceFeatures(*descriptor)
-          .GetExtension(pb::java)
-          .utf8_validation() == pb::JavaFeatures::VERIFY) {
-    return true;
-  }
-  return JavaGenerator::GetResolvedSourceFeatures(*descriptor)
-                 .utf8_validation() == FeatureSet::VERIFY ||
-         // For legacy syntax. This is not allowed under Editions.
-         descriptor->file()->options().java_string_check_utf8();
-}
-
 void WriteUInt32ToUtf16CharSequence(uint32_t number,
                                     std::vector<uint16_t>* output);
 
@@ -398,16 +372,6 @@ inline void WriteIntToUtf16CharSequence(int value,
 // Escape a UTF-16 character so it can be embedded in a Java string literal.
 void EscapeUtf16ToString(uint16_t code, std::string* output);
 
-// Only the lowest two bytes of the return value are used. The lowest byte
-// is the integer value of a j/c/g/protobuf/FieldType enum. For the other
-// byte:
-//    bit 0: whether the field is required.
-//    bit 1: whether the field requires UTF-8 validation.
-//    bit 2: whether the field needs isInitialized check.
-//    bit 3: whether the field is a map field with proto2 enum value.
-//    bits 4-7: unused
-int GetExperimentalJavaFieldType(const FieldDescriptor* field);
-
 // To get the total number of entries need to be built for experimental runtime
 // and the first field number that are not in the table part
 std::pair<int, int> GetTableDrivenNumberOfEntriesAndLookUpStartFieldNumber(

src/google/protobuf/compiler/java/immutable/BUILD.bazel

@@ -0,0 +1,132 @@
+# We use abbreviated target names in this directory to work around:
+#     https://github.com/bazelbuild/bazel/issues/18683
+cc_library(
+    name = "fg",
+    hdrs = ["field_generator.h"],
+    strip_include_prefix = "/src",
+    deps = [
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/io:printer",
+    ],
+)
+
+# We have to expose the field generators individually (instead of just through the factory) because
+# the mutable generators delegate to them directly.
+cc_library(
+    name = "fgs",
+    srcs = [
+        "enum_field.cc",
+        "map_field.cc",
+        "message_field.cc",
+        "primitive_field.cc",
+        "string_field.cc",
+    ],
+    hdrs = [
+        "enum_field.h",
+        "map_field.h",
+        "message_field.h",
+        "primitive_field.h",
+        "string_field.h",
+    ],
+    strip_include_prefix = "/src",
+    deps = [
+        ":fg",
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/compiler/java:helpers",
+        "//src/google/protobuf/compiler/java:internal_helpers",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/container:flat_hash_map",
+        "@com_google_absl//absl/log:absl_check",
+        "@com_google_absl//absl/log:absl_log",
+        "@com_google_absl//absl/strings",
+    ],
+)
+
+cc_library(
+    name = "mfg",
+    srcs = ["make_field_generators.cc"],
+    hdrs = ["make_field_generators.h"],
+    strip_include_prefix = "/src",
+    deps = [
+        ":fg",
+        ":fgs",
+        "//src/google/protobuf",
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/compiler/java:helpers",
+    ],
+)
+
+cc_library(
+    name = "service",
+    srcs = ["service.cc"],
+    hdrs = ["service.h"],
+    strip_include_prefix = "/src",
+    visibility = ["//src/google/protobuf/compiler/java/lite:__pkg__"],
+    deps = [
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/compiler/java:helpers",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/log:absl_log",
+        "@com_google_absl//absl/strings",
+    ],
+)
+
+cc_library(
+    name = "eg",
+    srcs = ["enum.cc"],
+    hdrs = ["enum.h"],
+    strip_include_prefix = "/src",
+    deps = [
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/compiler/java:helpers",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/container:flat_hash_map",
+        "@com_google_absl//absl/strings",
+    ],
+)
+
+cc_library(
+    name = "immutable",
+    srcs = [
+        "extension.cc",
+        "generator_factory.cc",
+        "message.cc",
+        "message.h",
+        "message_builder.cc",
+    ],
+    hdrs = [
+        "generator_factory.h",
+        # We don't actually want to put the remaining headers in `hdrs`.
+        # They are logically private, and should be in srcs=[], but
+        # unfortunately `strip_include_prefix` doesn't have any effect
+        # on headers listed in `srcs.`
+        "message.h",
+        "extension.h",
+        "message_builder.h",
+    ],
+    strip_include_prefix = "/src",
+    visibility = ["//src/google/protobuf/compiler/java:__pkg__"],
+    deps = [
+        ":eg",
+        ":fg",
+        ":mfg",
+        ":service",
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/compiler/java:helpers",
+        "//src/google/protobuf/compiler/java:message_serialization",
+        "//src/google/protobuf/io",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/container:btree",
+        "@com_google_absl//absl/container:flat_hash_map",
+        "@com_google_absl//absl/log:absl_check",
+        "@com_google_absl//absl/strings",
+    ],
+)

src/google/protobuf/compiler/java/immutable/enum.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/enum.h"
+#include "google/protobuf/compiler/java/immutable/enum.h"
 
 #include <string>
 
@@ -30,8 +30,8 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
-EnumGenerator::EnumGenerator(const EnumDescriptor* descriptor,
+EnumNonLiteGenerator::EnumNonLiteGenerator(const EnumDescriptor* descriptor,
-                             bool immutable_api, Context* context)
+                                           bool immutable_api, Context* context)
     : descriptor_(descriptor),
       immutable_api_(immutable_api),
       context_(context),
@@ -52,9 +52,7 @@ EnumGenerator::EnumGenerator(const EnumDescriptor* descriptor,
   }
 }
 
-EnumGenerator::~EnumGenerator() {}
+void EnumNonLiteGenerator::Generate(io::Printer* printer) {
-
-void EnumGenerator::Generate(io::Printer* printer) {
   WriteEnumDocComment(printer, descriptor_, context_->options());
   MaybePrintGeneratedAnnotation(context_, printer, descriptor_, immutable_api_);
 
@@ -376,7 +374,7 @@ void EnumGenerator::Generate(io::Printer* printer) {
   printer->Print("}\n\n");
 }
 
-bool EnumGenerator::CanUseEnumValues() {
+bool EnumNonLiteGenerator::CanUseEnumValues() {
   if (canonical_values_.size() != descriptor_->value_count()) {
     return false;
   }

src/google/protobuf/compiler/java/immutable/enum.h

@@ -15,6 +15,7 @@
 #include <string>
 #include <vector>
 
+#include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/descriptor.h"
 
 namespace google {
@@ -36,15 +37,17 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
-class EnumGenerator {
+// This class is in the immutable/ directory, but since the mutable API for
+// enums is nearly identical to the immutable one, we also use this for mutable
+// enums.  It is used for all enums except lite enums.
+class EnumNonLiteGenerator : public EnumGenerator {
  public:
-  EnumGenerator(const EnumDescriptor* descriptor, bool immutable_api,
+  EnumNonLiteGenerator(const EnumDescriptor* descriptor, bool immutable_api,
-                Context* context);
+                       Context* context);
-  EnumGenerator(const EnumGenerator&) = delete;
+  EnumNonLiteGenerator(const EnumNonLiteGenerator&) = delete;
-  EnumGenerator& operator=(const EnumGenerator&) = delete;
+  EnumNonLiteGenerator& operator=(const EnumNonLiteGenerator&) = delete;
-  ~EnumGenerator();
 
-  void Generate(io::Printer* printer);
+  void Generate(io::Printer* printer) override;
 
  private:
   const EnumDescriptor* descriptor_;

src/google/protobuf/compiler/java/immutable/enum_field.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/enum_field.h"
+#include "google/protobuf/compiler/java/immutable/enum_field.h"
 
 #include <cstdint>
 #include <string>
@@ -20,7 +20,9 @@
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
 #include "google/protobuf/wire_format.h"

src/google/protobuf/compiler/java/immutable/enum_field.h

@@ -15,7 +15,9 @@
 #include <string>
 
 #include "absl/container/flat_hash_map.h"
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
+#include "google/protobuf/io/printer.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/immutable/extension.cc

@@ -9,13 +9,10 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/extension.h"
+#include "google/protobuf/compiler/java/immutable/extension.h"
 
-#include "absl/container/flat_hash_map.h"
-#include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
-#include "google/protobuf/compiler/java/helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
 

src/google/protobuf/compiler/java/immutable/extension.h

@@ -15,6 +15,7 @@
 #include <string>
 
 #include "absl/container/flat_hash_map.h"
+#include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/port.h"
 
 namespace google {
@@ -37,34 +38,6 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
-// Generates code for an extension, which may be within the scope of some
-// message or may be at file scope.  This is much simpler than FieldGenerator
-// since extensions are just simple identifiers with interesting types.
-class ExtensionGenerator {
- public:
-  explicit ExtensionGenerator() {}
-  ExtensionGenerator(const ExtensionGenerator&) = delete;
-  ExtensionGenerator& operator=(const ExtensionGenerator&) = delete;
-  virtual ~ExtensionGenerator() {}
-
-  virtual void Generate(io::Printer* printer) = 0;
-
-  // Returns an estimate of the number of bytes the printed code will compile
-  // to
-  virtual int GenerateNonNestedInitializationCode(io::Printer* printer) = 0;
-
-  // Returns an estimate of the number of bytes the printed code will compile
-  // to
-  virtual int GenerateRegistrationCode(io::Printer* printer) = 0;
-
- protected:
-  static void InitTemplateVars(
-      const FieldDescriptor* descriptor, const std::string& scope,
-      bool immutable, ClassNameResolver* name_resolver,
-      absl::flat_hash_map<absl::string_view, std::string>* vars_pointer,
-      Context* context);
-};
-
 class ImmutableExtensionGenerator : public ExtensionGenerator {
  public:
   explicit ImmutableExtensionGenerator(const FieldDescriptor* descriptor,

src/google/protobuf/compiler/java/immutable/field_generator.h

@@ -0,0 +1,54 @@
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_FIELD_GENERATOR_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_FIELD_GENERATOR_H__
+
+#include <string>
+
+#include "google/protobuf/compiler/java/generator_common.h"
+#include "google/protobuf/io/printer.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+class ImmutableFieldGenerator : public FieldGenerator {
+ public:
+  ImmutableFieldGenerator() = default;
+  ImmutableFieldGenerator(const ImmutableFieldGenerator&) = delete;
+  ImmutableFieldGenerator& operator=(const ImmutableFieldGenerator&) = delete;
+  ~ImmutableFieldGenerator() override = default;
+
+  virtual int GetMessageBitIndex() const = 0;
+  virtual int GetBuilderBitIndex() const = 0;
+  virtual int GetNumBitsForMessage() const = 0;
+  virtual int GetNumBitsForBuilder() const = 0;
+  virtual void GenerateInterfaceMembers(io::Printer* printer) const = 0;
+  virtual void GenerateMembers(io::Printer* printer) const = 0;
+  virtual void GenerateBuilderMembers(io::Printer* printer) const = 0;
+  virtual void GenerateInitializationCode(io::Printer* printer) const = 0;
+  virtual void GenerateBuilderClearCode(io::Printer* printer) const = 0;
+  virtual void GenerateMergingCode(io::Printer* printer) const = 0;
+  virtual void GenerateBuildingCode(io::Printer* printer) const = 0;
+  virtual void GenerateBuilderParsingCode(io::Printer* printer) const = 0;
+  virtual void GenerateSerializedSizeCode(io::Printer* printer) const = 0;
+  virtual void GenerateFieldBuilderInitializationCode(
+      io::Printer* printer) const = 0;
+  virtual void GenerateKotlinDslMembers(io::Printer* printer) const = 0;
+
+  virtual void GenerateBuilderParsingCodeFromPacked(
+      io::Printer* printer) const {
+    ReportUnexpectedPackedFieldsCall();
+  }
+
+  virtual void GenerateEqualsCode(io::Printer* printer) const = 0;
+  virtual void GenerateHashCode(io::Printer* printer) const = 0;
+
+  virtual std::string GetBoxedType() const = 0;
+};
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_FIELD_GENERATOR_H__

src/google/protobuf/compiler/java/immutable/generator_factory.cc

@@ -0,0 +1,67 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+// Author: liujisi@google.com (Pherl Liu)
+
+#include "google/protobuf/compiler/java/generator_factory.h"
+
+#include <memory>
+
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/immutable/enum.h"
+#include "google/protobuf/compiler/java/immutable/extension.h"
+#include "google/protobuf/compiler/java/immutable/message.h"
+#include "google/protobuf/compiler/java/immutable/service.h"
+#include "google/protobuf/descriptor.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+// Factory that creates generators for immutable-default messages.
+class ImmutableGeneratorFactory : public GeneratorFactory {
+ public:
+  explicit ImmutableGeneratorFactory(Context* context) : context_(context) {}
+  ImmutableGeneratorFactory(const ImmutableGeneratorFactory&) = delete;
+  ImmutableGeneratorFactory& operator=(const ImmutableGeneratorFactory&) =
+      delete;
+  ~ImmutableGeneratorFactory() override = default;
+
+  std::unique_ptr<MessageGenerator> NewMessageGenerator(
+      const Descriptor* descriptor) const override {
+    return std::make_unique<ImmutableMessageGenerator>(descriptor, context_);
+  }
+
+  std::unique_ptr<EnumGenerator> NewEnumGenerator(
+      const EnumDescriptor* descriptor) const override {
+    return std::make_unique<EnumNonLiteGenerator>(descriptor, true, context_);
+  }
+
+  std::unique_ptr<ExtensionGenerator> NewExtensionGenerator(
+      const FieldDescriptor* descriptor) const override {
+    return std::make_unique<ImmutableExtensionGenerator>(descriptor, context_);
+  }
+
+  std::unique_ptr<ServiceGenerator> NewServiceGenerator(
+      const ServiceDescriptor* descriptor) const override {
+    return std::make_unique<ImmutableServiceGenerator>(descriptor, context_);
+  }
+
+ private:
+  Context* context_;
+};
+
+std::unique_ptr<GeneratorFactory> MakeImmutableGeneratorFactory(
+    Context* context) {
+  return std::make_unique<ImmutableGeneratorFactory>(context);
+}
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google

src/google/protobuf/compiler/java/immutable/generator_factory.h

@@ -0,0 +1,19 @@
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_GENERATOR_FACTORY_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_GENERATOR_FACTORY_H__
+
+#include "google/protobuf/compiler/java/generator_factory.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+std::unique_ptr<GeneratorFactory> MakeImmutableGeneratorFactory(
+    Context* context);
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_GENERATOR_FACTORY_H__

src/google/protobuf/compiler/java/immutable/make_field_generators.cc

@@ -0,0 +1,114 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+// Author: kenton@google.com (Kenton Varda)
+//  Based on original Protocol Buffers design by
+//  Sanjay Ghemawat, Jeff Dean, and others.
+
+#include <memory>
+#include <utility>
+
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/generator_common.h"
+#include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/immutable/enum_field.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/compiler/java/immutable/map_field.h"
+#include "google/protobuf/compiler/java/immutable/message_field.h"
+#include "google/protobuf/compiler/java/immutable/primitive_field.h"
+#include "google/protobuf/compiler/java/immutable/string_field.h"
+#include "google/protobuf/descriptor.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+namespace {
+
+std::unique_ptr<ImmutableFieldGenerator> MakeImmutableGenerator(
+    const FieldDescriptor* field, int messageBitIndex, int builderBitIndex,
+    Context* context) {
+  if (field->is_repeated()) {
+    switch (GetJavaType(field)) {
+      case JAVATYPE_MESSAGE:
+        if (IsMapEntry(field->message_type())) {
+          return std::make_unique<ImmutableMapFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        } else {
+          return std::make_unique<RepeatedImmutableMessageFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        }
+      case JAVATYPE_ENUM:
+        return std::make_unique<RepeatedImmutableEnumFieldGenerator>(
+            field, messageBitIndex, builderBitIndex, context);
+      case JAVATYPE_STRING:
+        return std::make_unique<RepeatedImmutableStringFieldGenerator>(
+            field, messageBitIndex, builderBitIndex, context);
+      default:
+        return std::make_unique<RepeatedImmutablePrimitiveFieldGenerator>(
+            field, messageBitIndex, builderBitIndex, context);
+    }
+  } else {
+    if (IsRealOneof(field)) {
+      switch (GetJavaType(field)) {
+        case JAVATYPE_MESSAGE:
+          return std::make_unique<ImmutableMessageOneofFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        case JAVATYPE_ENUM:
+          return std::make_unique<ImmutableEnumOneofFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        case JAVATYPE_STRING:
+          return std::make_unique<ImmutableStringOneofFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        default:
+          return std::make_unique<ImmutablePrimitiveOneofFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+      }
+    } else {
+      switch (GetJavaType(field)) {
+        case JAVATYPE_MESSAGE:
+          return std::make_unique<ImmutableMessageFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        case JAVATYPE_ENUM:
+          return std::make_unique<ImmutableEnumFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        case JAVATYPE_STRING:
+          return std::make_unique<ImmutableStringFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+        default:
+          return std::make_unique<ImmutablePrimitiveFieldGenerator>(
+              field, messageBitIndex, builderBitIndex, context);
+      }
+    }
+  }
+}
+
+}  // namespace
+
+FieldGeneratorMap<ImmutableFieldGenerator> MakeImmutableFieldGenerators(
+    const Descriptor* descriptor, Context* context) {
+  // Construct all the FieldGenerators and assign them bit indices for their
+  // bit fields.
+  int messageBitIndex = 0;
+  int builderBitIndex = 0;
+  FieldGeneratorMap<ImmutableFieldGenerator> ret(descriptor);
+  for (int i = 0; i < descriptor->field_count(); i++) {
+    const FieldDescriptor* field = descriptor->field(i);
+    auto generator = MakeImmutableGenerator(field, messageBitIndex,
+                                            builderBitIndex, context);
+    messageBitIndex += generator->GetNumBitsForMessage();
+    builderBitIndex += generator->GetNumBitsForBuilder();
+    ret.Add(field, std::move(generator));
+  }
+  return ret;
+}
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google

src/google/protobuf/compiler/java/immutable/make_field_generators.h

@@ -0,0 +1,29 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2024 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_MAKE_FIELD_GENERATORS_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_MAKE_FIELD_GENERATORS_H__
+
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/generator_common.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+FieldGeneratorMap<ImmutableFieldGenerator> MakeImmutableFieldGenerators(
+    const Descriptor* descriptor, Context* context);
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_MAKE_FIELD_GENERATORS_H__

src/google/protobuf/compiler/java/immutable/map_field.cc

@@ -5,7 +5,7 @@
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd
 
-#include "google/protobuf/compiler/java/map_field.h"
+#include "google/protobuf/compiler/java/immutable/map_field.h"
 
 #include <string>
 
@@ -13,8 +13,9 @@
 #include "absl/strings/str_join.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
 

src/google/protobuf/compiler/java/immutable/map_field.h

@@ -8,7 +8,10 @@
 #ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_MAP_FIELD_H__
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_MAP_FIELD_H__
 
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
+#include "google/protobuf/io/printer.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/immutable/message.cc

@@ -9,24 +9,29 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/message.h"
+#include "google/protobuf/compiler/java/immutable/message.h"
 
 #include <algorithm>
 #include <cstdint>
 #include <memory>
+#include <string>
 #include <vector>
 
+#include "absl/container/flat_hash_map.h"
+#include "absl/log/absl_check.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/str_cat.h"
+#include "absl/strings/string_view.h"
 #include "absl/strings/substitute.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
-#include "google/protobuf/compiler/java/enum.h"
+#include "google/protobuf/compiler/java/field_common.h"
-#include "google/protobuf/compiler/java/extension.h"
+#include "google/protobuf/compiler/java/generator_common.h"
-#include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/compiler/java/helpers.h"
-#include "google/protobuf/compiler/java/message_builder.h"
+#include "google/protobuf/compiler/java/immutable/enum.h"
-#include "google/protobuf/compiler/java/message_builder_lite.h"
+#include "google/protobuf/compiler/java/immutable/extension.h"
+#include "google/protobuf/compiler/java/immutable/make_field_generators.h"
+#include "google/protobuf/compiler/java/immutable/message_builder.h"
 #include "google/protobuf/compiler/java/message_serialization.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/descriptor.h"
@@ -75,7 +80,7 @@ ImmutableMessageGenerator::ImmutableMessageGenerator(
     : MessageGenerator(descriptor),
       context_(context),
       name_resolver_(context->GetNameResolver()),
-      field_generators_(descriptor, context_) {
+      field_generators_(MakeImmutableFieldGenerators(descriptor, context_)) {
   ABSL_CHECK(HasDescriptorMethods(descriptor->file(), context->EnforceLite()))
       << "Generator factory error: A non-lite message generator is used to "
          "generate lite messages.";
@@ -362,7 +367,8 @@ void ImmutableMessageGenerator::Generate(io::Printer* printer) {
 
   // Nested types
   for (int i = 0; i < descriptor_->enum_type_count(); i++) {
-    EnumGenerator(descriptor_->enum_type(i), true, context_).Generate(printer);
+    EnumNonLiteGenerator(descriptor_->enum_type(i), true, context_)
+        .Generate(printer);
   }
 
   for (int i = 0; i < descriptor_->nested_type_count(); i++) {
@@ -593,8 +599,9 @@ void ImmutableMessageGenerator::GenerateMessageSerializationMethods(
     }
   }
 
-  GenerateSerializeFieldsAndExtensions(printer, field_generators_, descriptor_,
+  GenerateSerializeFieldsAndExtensions(printer,
-                                       sorted_fields.get());
+                                       field_generators_.field_generators(),
+                                       descriptor_, sorted_fields.get());
 
   if (descriptor_->options().message_set_wire_format()) {
     printer->Print("getUnknownFields().writeAsMessageSetTo(output);\n");

src/google/protobuf/compiler/java/immutable/message.h

@@ -12,10 +12,13 @@
 #ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_MESSAGE_H__
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_MESSAGE_H__
 
+#include <memory>
 #include <string>
+#include <vector>
 
-#include "absl/container/btree_map.h"
+#include "google/protobuf/compiler/java/generator_factory.h"
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {
@@ -36,44 +39,6 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
-static const int kMaxStaticSize = 1 << 15;  // aka 32k
-
-class MessageGenerator {
- public:
-  explicit MessageGenerator(const Descriptor* descriptor);
-  MessageGenerator(const MessageGenerator&) = delete;
-  MessageGenerator& operator=(const MessageGenerator&) = delete;
-  virtual ~MessageGenerator();
-
-  // All static variables have to be declared at the top-level of the file
-  // so that we can control initialization order, which is important for
-  // DescriptorProto bootstrapping to work.
-  virtual void GenerateStaticVariables(io::Printer* printer,
-                                       int* bytecode_estimate) = 0;
-
-  // Output code which initializes the static variables generated by
-  // GenerateStaticVariables(). Returns an estimate of bytecode size.
-  virtual int GenerateStaticVariableInitializers(io::Printer* printer) = 0;
-
-  // Generate the class itself.
-  virtual void Generate(io::Printer* printer) = 0;
-
-  // Generates the base interface that both the class and its builder
-  // implement
-  virtual void GenerateInterface(io::Printer* printer) = 0;
-
-  // Generate code to register all contained extensions with an
-  // ExtensionRegistry.
-  virtual void GenerateExtensionRegistrationCode(io::Printer* printer) = 0;
-  virtual void GenerateKotlinDsl(io::Printer* printer) const = 0;
-  virtual void GenerateKotlinMembers(io::Printer* printer) const = 0;
-  virtual void GenerateTopLevelKotlinMembers(io::Printer* printer) const = 0;
-
- protected:
-  const Descriptor* descriptor_;
-  absl::btree_map<int, const OneofDescriptor*> oneofs_;
-};
-
 class ImmutableMessageGenerator : public MessageGenerator {
  public:
   ImmutableMessageGenerator(const Descriptor* descriptor, Context* context);

src/google/protobuf/compiler/java/immutable/message_builder.cc

@@ -9,21 +9,28 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/message_builder.h"
+#include "google/protobuf/compiler/java/immutable/message_builder.h"
 
+#include <cstdint>
 #include <memory>
+#include <string>
 #include <vector>
 
 #include "absl/container/btree_set.h"
 #include "absl/container/flat_hash_map.h"
+#include "absl/log/absl_check.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/str_cat.h"
+#include "absl/strings/string_view.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
-#include "google/protobuf/compiler/java/enum.h"
+#include "google/protobuf/compiler/java/field_common.h"
-#include "google/protobuf/compiler/java/extension.h"
 #include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/immutable/enum.h"
+#include "google/protobuf/compiler/java/immutable/extension.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/compiler/java/immutable/make_field_generators.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/descriptor.pb.h"
 #include "google/protobuf/io/printer.h"
@@ -73,7 +80,7 @@ MessageBuilderGenerator::MessageBuilderGenerator(const Descriptor* descriptor,
     : descriptor_(descriptor),
       context_(context),
       name_resolver_(context->GetNameResolver()),
-      field_generators_(descriptor, context_) {
+      field_generators_(MakeImmutableFieldGenerators(descriptor, context_)) {
   ABSL_CHECK(HasDescriptorMethods(descriptor->file(), context->EnforceLite()))
       << "Generator factory error: A non-lite message generator is used to "
          "generate lite messages.";

src/google/protobuf/compiler/java/immutable/message_builder.h

@@ -12,10 +12,13 @@
 #ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_MESSAGE_BUILDER_H__
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_MESSAGE_BUILDER_H__
 
+#include <memory>
 #include <string>
+#include <vector>
 
 #include "absl/container/btree_map.h"
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/immutable/message_field.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/message_field.h"
+#include "google/protobuf/compiler/java/immutable/message_field.h"
 
 #include <string>
 
@@ -17,10 +17,10 @@
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
-#include "google/protobuf/wire_format.h"
 
 // Must be last.
 #include "google/protobuf/port_def.inc"

src/google/protobuf/compiler/java/immutable/message_field.h

@@ -14,7 +14,8 @@
 
 #include <string>
 
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
 #include "google/protobuf/io/printer.h"
 
 namespace google {

src/google/protobuf/compiler/java/immutable/primitive_field.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/primitive_field.h"
+#include "google/protobuf/compiler/java/immutable/primitive_field.h"
 
 #include <cstdint>
 #include <string>
@@ -19,6 +19,7 @@
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/descriptor.h"

src/google/protobuf/compiler/java/immutable/primitive_field.h

@@ -14,7 +14,8 @@
 
 #include <string>
 
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/immutable/service.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/service.h"
+#include "google/protobuf/compiler/java/immutable/service.h"
 
 #include "absl/log/absl_log.h"
 #include "absl/strings/str_cat.h"
@@ -27,12 +27,6 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
-ServiceGenerator::ServiceGenerator(const ServiceDescriptor* descriptor)
-    : descriptor_(descriptor) {}
-
-ServiceGenerator::~ServiceGenerator() {}
-
-// ===================================================================
 ImmutableServiceGenerator::ImmutableServiceGenerator(
     const ServiceDescriptor* descriptor, Context* context)
     : ServiceGenerator(descriptor),

src/google/protobuf/compiler/java/immutable/service.h

@@ -12,6 +12,7 @@
 #ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_SERVICE_H__
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_SERVICE_H__
 
+#include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/descriptor.h"
 
 namespace google {
@@ -33,22 +34,6 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
-class ServiceGenerator {
- public:
-  explicit ServiceGenerator(const ServiceDescriptor* descriptor);
-  ServiceGenerator(const ServiceGenerator&) = delete;
-  ServiceGenerator& operator=(const ServiceGenerator&) = delete;
-  virtual ~ServiceGenerator();
-
-  virtual void Generate(io::Printer* printer) = 0;
-
-  enum RequestOrResponse { REQUEST, RESPONSE };
-  enum IsAbstract { IS_ABSTRACT, IS_CONCRETE };
-
- protected:
-  const ServiceDescriptor* descriptor_;
-};
-
 class ImmutableServiceGenerator : public ServiceGenerator {
  public:
   ImmutableServiceGenerator(const ServiceDescriptor* descriptor,

src/google/protobuf/compiler/java/immutable/string_field.cc

@@ -10,7 +10,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/string_field.h"
+#include "google/protobuf/compiler/java/immutable/string_field.h"
 
 #include <cstdint>
 #include <string>
@@ -20,7 +20,9 @@
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
 #include "google/protobuf/wire_format.h"

src/google/protobuf/compiler/java/immutable/string_field.h

@@ -15,7 +15,8 @@
 
 #include <string>
 
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/immutable/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/internal_helpers.cc

@@ -0,0 +1,114 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+// Author: kenton@google.com (Kenton Varda)
+//  Based on original Protocol Buffers design by
+//  Sanjay Ghemawat, Jeff Dean, and others.
+
+#include "google/protobuf/compiler/java/internal_helpers.h"
+
+#include "absl/log/absl_log.h"
+#include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/name_resolver.h"
+#include "google/protobuf/descriptor.pb.h"
+
+// Must be last.
+#include "google/protobuf/port_def.inc"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+namespace {
+
+int GetExperimentalJavaFieldTypeForSingular(const FieldDescriptor* field) {
+  // j/c/g/protobuf/FieldType.java lists field types in a slightly different
+  // order from FieldDescriptor::Type so we can't do a simple cast.
+  //
+  // TODO: Make j/c/g/protobuf/FieldType.java follow the same order.
+  int result = field->type();
+  if (result == FieldDescriptor::TYPE_GROUP) {
+    return 17;
+  } else if (result < FieldDescriptor::TYPE_GROUP) {
+    return result - 1;
+  } else {
+    return result - 2;
+  }
+}
+
+int GetExperimentalJavaFieldTypeForRepeated(const FieldDescriptor* field) {
+  if (field->type() == FieldDescriptor::TYPE_GROUP) {
+    return 49;
+  } else {
+    return GetExperimentalJavaFieldTypeForSingular(field) + 18;
+  }
+}
+
+int GetExperimentalJavaFieldTypeForPacked(const FieldDescriptor* field) {
+  int result = field->type();
+  if (result < FieldDescriptor::TYPE_STRING) {
+    return result + 34;
+  } else if (result > FieldDescriptor::TYPE_BYTES) {
+    return result + 30;
+  } else {
+    ABSL_LOG(FATAL) << field->full_name() << " can't be packed.";
+    return 0;
+  }
+}
+}  // namespace
+
+int GetExperimentalJavaFieldType(const FieldDescriptor* field) {
+  static const int kMapFieldType = 50;
+  static const int kOneofFieldTypeOffset = 51;
+
+  static const int kRequiredBit = 0x100;
+  static const int kUtf8CheckBit = 0x200;
+  static const int kCheckInitialized = 0x400;
+  static const int kLegacyEnumIsClosedBit = 0x800;
+  static const int kHasHasBit = 0x1000;
+  int extra_bits = field->is_required() ? kRequiredBit : 0;
+  if (field->type() == FieldDescriptor::TYPE_STRING && CheckUtf8(field)) {
+    extra_bits |= kUtf8CheckBit;
+  }
+  if (field->is_required() || (GetJavaType(field) == JAVATYPE_MESSAGE &&
+                               HasRequiredFields(field->message_type()))) {
+    extra_bits |= kCheckInitialized;
+  }
+  if (HasHasbit(field)) {
+    extra_bits |= kHasHasBit;
+  }
+  if (GetJavaType(field) == JAVATYPE_ENUM && !SupportUnknownEnumValue(field)) {
+    extra_bits |= kLegacyEnumIsClosedBit;
+  }
+
+  if (field->is_map()) {
+    if (!SupportUnknownEnumValue(MapValueField(field))) {
+      const FieldDescriptor* value = field->message_type()->map_value();
+      if (GetJavaType(value) == JAVATYPE_ENUM) {
+        extra_bits |= kLegacyEnumIsClosedBit;
+      }
+    }
+    return kMapFieldType | extra_bits;
+  } else if (field->is_packed()) {
+    return GetExperimentalJavaFieldTypeForPacked(field) | extra_bits;
+  } else if (field->is_repeated()) {
+    return GetExperimentalJavaFieldTypeForRepeated(field) | extra_bits;
+  } else if (IsRealOneof(field)) {
+    return (GetExperimentalJavaFieldTypeForSingular(field) +
+            kOneofFieldTypeOffset) |
+           extra_bits;
+  } else {
+    return GetExperimentalJavaFieldTypeForSingular(field) | extra_bits;
+  }
+}
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#include "google/protobuf/port_undef.inc"

src/google/protobuf/compiler/java/internal_helpers.h

@@ -0,0 +1,69 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+// Author: kenton@google.com (Kenton Varda)
+//  Based on original Protocol Buffers design by
+//  Sanjay Ghemawat, Jeff Dean, and others.
+
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_INTERNAL_HELPERS_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_INTERNAL_HELPERS_H__
+
+#include "google/protobuf/compiler/java/generator.h"
+#include "google/protobuf/compiler/java/java_features.pb.h"
+#include "google/protobuf/compiler/java/names.h"
+#include "google/protobuf/descriptor.h"
+#include "google/protobuf/descriptor.pb.h"
+
+// Must be last.
+#include "google/protobuf/port_def.inc"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+// Whether unknown enum values are kept (i.e., not stored in UnknownFieldSet
+// but in the message and can be queried using additional getters that return
+// ints.
+inline bool SupportUnknownEnumValue(const FieldDescriptor* field) {
+  if (JavaGenerator::GetResolvedSourceFeatures(*field)
+          .GetExtension(pb::java)
+          .legacy_closed_enum()) {
+    return false;
+  }
+  return field->enum_type() != nullptr && !field->enum_type()->is_closed();
+}
+
+inline bool CheckUtf8(const FieldDescriptor* descriptor) {
+  if (JavaGenerator::GetResolvedSourceFeatures(*descriptor)
+          .GetExtension(pb::java)
+          .utf8_validation() == pb::JavaFeatures::VERIFY) {
+    return true;
+  }
+  return JavaGenerator::GetResolvedSourceFeatures(*descriptor)
+                 .utf8_validation() == FeatureSet::VERIFY ||
+         // For legacy syntax. This is not allowed under Editions.
+         descriptor->file()->options().java_string_check_utf8();
+}
+
+// Only the lowest two bytes of the return value are used. The lowest byte
+// is the integer value of a j/c/g/protobuf/FieldType enum. For the other
+// byte:
+//    bit 0: whether the field is required.
+//    bit 1: whether the field requires UTF-8 validation.
+//    bit 2: whether the field needs isInitialized check.
+//    bit 3: whether the field is a map field with proto2 enum value.
+//    bits 4-7: unused
+int GetExperimentalJavaFieldType(const FieldDescriptor* field);
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#include "google/protobuf/port_undef.inc"
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_INTERNAL_HELPERS_H__

src/google/protobuf/compiler/java/lite/BUILD.bazel

@@ -0,0 +1,79 @@
+cc_library(
+    name = "field_generators",
+    srcs = [
+        "enum_field.cc",
+        "extension.cc",
+        "make_field_generators.cc",
+        "map_field.cc",
+        "message_field.cc",
+        "primitive_field.cc",
+        "string_field.cc",
+    ],
+    hdrs = [
+        "field_generator.h",
+        "make_field_generators.h",
+        # We don't actually want to put the remaining headers in `hdrs`.
+        # They are logically private, and should be in srcs=[], but
+        # unfortunately `strip_include_prefix` doesn't have any effect
+        # on headers listed in `srcs.`
+        "map_field.h",
+        "enum_field.h",
+        "extension.h",
+        "message_field.h",
+        "primitive_field.h",
+        "string_field.h",
+    ],
+    strip_include_prefix = "/src",
+    visibility = ["//src/google/protobuf/compiler/java:__subpackages__"],
+    deps = [
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/compiler/java:helpers",
+        "//src/google/protobuf/compiler/java:internal_helpers",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/container:flat_hash_map",
+        "@com_google_absl//absl/log:absl_check",
+        "@com_google_absl//absl/log:absl_log",
+        "@com_google_absl//absl/strings",
+    ],
+)
+
+cc_library(
+    name = "lite",
+    srcs = [
+        "enum.cc",
+        "extension.cc",
+        "generator_factory.cc",
+        "message.cc",
+        "message_builder.cc",
+    ],
+    hdrs = [
+        "generator_factory.h",
+        # We don't actually want to put the remaining headers in `hdrs`.
+        # They are logically private, and should be in srcs=[], but
+        # unfortunately `strip_include_prefix` doesn't have any effect
+        # on headers listed in `srcs.`
+        "enum.h",
+        "extension.h",
+        "message.h",
+        "message_builder.h",
+    ],
+    strip_include_prefix = "/src",
+    visibility = ["//src/google/protobuf/compiler/java:__subpackages__"],
+    deps = [
+        ":field_generators",
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler/java:generator_common",
+        "//src/google/protobuf/compiler/java:helpers",
+        "//src/google/protobuf/compiler/java:internal_helpers",
+        "//src/google/protobuf/compiler/java/immutable:service",
+        "//src/google/protobuf/io",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/container:btree",
+        "@com_google_absl//absl/container:flat_hash_map",
+        "@com_google_absl//absl/log:absl_check",
+        "@com_google_absl//absl/strings",
+    ],
+)

src/google/protobuf/compiler/java/lite/enum.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/enum_lite.h"
+#include "google/protobuf/compiler/java/lite/enum.h"
 
 #include <string>
 

src/google/protobuf/compiler/java/lite/enum.h

@@ -15,6 +15,7 @@
 #include <string>
 #include <vector>
 
+#include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/descriptor.h"
 
 namespace google {
@@ -36,7 +37,7 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
-class EnumLiteGenerator {
+class EnumLiteGenerator : public EnumGenerator {
  public:
   EnumLiteGenerator(const EnumDescriptor* descriptor, bool immutable_api,
                     Context* context);
@@ -44,7 +45,7 @@ class EnumLiteGenerator {
   EnumLiteGenerator& operator=(const EnumLiteGenerator&) = delete;
   ~EnumLiteGenerator();
 
-  void Generate(io::Printer* printer);
+  void Generate(io::Printer* printer) override;
 
  private:
   const EnumDescriptor* descriptor_;

src/google/protobuf/compiler/java/lite/enum_field.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/enum_field_lite.h"
+#include "google/protobuf/compiler/java/lite/enum_field.h"
 
 #include <cstdint>
 #include <string>
@@ -17,10 +17,11 @@
 #include "absl/container/flat_hash_map.h"
 #include "absl/log/absl_check.h"
 #include "absl/strings/str_cat.h"
-#include "absl/strings/str_join.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
 #include "google/protobuf/wire_format.h"

src/google/protobuf/compiler/java/lite/enum_field.h

@@ -16,7 +16,8 @@
 #include <string>
 
 #include "absl/container/flat_hash_map.h"
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/lite/extension.cc

@@ -5,7 +5,7 @@
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd
 
-#include "google/protobuf/compiler/java/extension_lite.h"
+#include "google/protobuf/compiler/java/lite/extension.h"
 
 #include <string>
 

src/google/protobuf/compiler/java/lite/extension.h

@@ -10,7 +10,8 @@
 
 #include <string>
 
-#include "google/protobuf/compiler/java/extension.h"
+#include "google/protobuf/compiler/java/generator_factory.h"
+#include "google/protobuf/descriptor.h"
 #include "google/protobuf/port.h"
 
 namespace google {

src/google/protobuf/compiler/java/lite/field_generator.h

@@ -0,0 +1,38 @@
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_FIELD_GENERATOR_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_FIELD_GENERATOR_H__
+
+#include <string>
+
+#include "google/protobuf/io/printer.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+class ImmutableFieldLiteGenerator {
+ public:
+  ImmutableFieldLiteGenerator() = default;
+  ImmutableFieldLiteGenerator(const ImmutableFieldLiteGenerator&) = delete;
+  ImmutableFieldLiteGenerator& operator=(const ImmutableFieldLiteGenerator&) =
+      delete;
+  virtual ~ImmutableFieldLiteGenerator() = default;
+
+  virtual int GetNumBitsForMessage() const = 0;
+  virtual void GenerateInterfaceMembers(io::Printer* printer) const = 0;
+  virtual void GenerateMembers(io::Printer* printer) const = 0;
+  virtual void GenerateBuilderMembers(io::Printer* printer) const = 0;
+  virtual void GenerateInitializationCode(io::Printer* printer) const = 0;
+  virtual void GenerateFieldInfo(io::Printer* printer,
+                                 std::vector<uint16_t>* output) const = 0;
+  virtual void GenerateKotlinDslMembers(io::Printer* printer) const = 0;
+
+  virtual std::string GetBoxedType() const = 0;
+};
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_IMMUTABLE_FIELD_GENERATOR_H__

src/google/protobuf/compiler/java/lite/generator_factory.cc

@@ -0,0 +1,70 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+// Author: liujisi@google.com (Pherl Liu)
+
+#include "google/protobuf/compiler/java/generator_factory.h"
+
+#include <memory>
+
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/immutable/service.h"
+#include "google/protobuf/compiler/java/lite/enum.h"
+#include "google/protobuf/compiler/java/lite/extension.h"
+#include "google/protobuf/compiler/java/lite/message.h"
+#include "google/protobuf/descriptor.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+// Factory that creates generators for immutable-default messages.
+class ImmutableLiteGeneratorFactory : public GeneratorFactory {
+ public:
+  explicit ImmutableLiteGeneratorFactory(Context* context)
+      : context_(context) {}
+  ImmutableLiteGeneratorFactory(const ImmutableLiteGeneratorFactory&) = delete;
+  ImmutableLiteGeneratorFactory& operator=(
+      const ImmutableLiteGeneratorFactory&) = delete;
+  ~ImmutableLiteGeneratorFactory() override = default;
+
+  std::unique_ptr<MessageGenerator> NewMessageGenerator(
+      const Descriptor* descriptor) const override {
+    return std::make_unique<ImmutableMessageLiteGenerator>(descriptor,
+                                                           context_);
+  }
+
+  std::unique_ptr<EnumGenerator> NewEnumGenerator(
+      const EnumDescriptor* descriptor) const override {
+    return std::make_unique<EnumLiteGenerator>(descriptor, true, context_);
+  }
+
+  std::unique_ptr<ExtensionGenerator> NewExtensionGenerator(
+      const FieldDescriptor* descriptor) const override {
+    return std::make_unique<ImmutableExtensionLiteGenerator>(descriptor,
+                                                             context_);
+  }
+
+  std::unique_ptr<ServiceGenerator> NewServiceGenerator(
+      const ServiceDescriptor* descriptor) const override {
+    return std::make_unique<ImmutableServiceGenerator>(descriptor, context_);
+  }
+
+ private:
+  Context* context_;
+};
+
+std::unique_ptr<GeneratorFactory> MakeImmutableLiteGeneratorFactory(
+    Context* context) {
+  return std::make_unique<ImmutableLiteGeneratorFactory>(context);
+}
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google

src/google/protobuf/compiler/java/lite/generator_factory.h

@@ -0,0 +1,19 @@
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_LITE_GENERATOR_FACTORY_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_LITE_GENERATOR_FACTORY_H__
+
+#include "google/protobuf/compiler/java/generator_factory.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+std::unique_ptr<GeneratorFactory> MakeImmutableLiteGeneratorFactory(
+    Context* context);
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_LITE_GENERATOR_FACTORY_H__

src/google/protobuf/compiler/java/lite/make_field_generators.cc

@@ -0,0 +1,110 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+// Author: kenton@google.com (Kenton Varda)
+//  Based on original Protocol Buffers design by
+//  Sanjay Ghemawat, Jeff Dean, and others.
+
+#include "google/protobuf/compiler/java/lite/make_field_generators.h"
+
+#include <memory>
+#include <utility>
+
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/generator_common.h"
+#include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/lite/enum_field.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/compiler/java/lite/map_field.h"
+#include "google/protobuf/compiler/java/lite/message_field.h"
+#include "google/protobuf/compiler/java/lite/primitive_field.h"
+#include "google/protobuf/compiler/java/lite/string_field.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+namespace {
+
+std::unique_ptr<ImmutableFieldLiteGenerator> CreateImmutableLiteGenerator(
+    const FieldDescriptor* field, int messageBitIndex, Context* context) {
+  if (field->is_repeated()) {
+    switch (GetJavaType(field)) {
+      case JAVATYPE_MESSAGE:
+        if (IsMapEntry(field->message_type())) {
+          return std::make_unique<ImmutableMapFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        } else {
+          return std::make_unique<RepeatedImmutableMessageFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        }
+      case JAVATYPE_ENUM:
+        return std::make_unique<RepeatedImmutableEnumFieldLiteGenerator>(
+            field, messageBitIndex, context);
+      case JAVATYPE_STRING:
+        return std::make_unique<RepeatedImmutableStringFieldLiteGenerator>(
+            field, messageBitIndex, context);
+      default:
+        return std::make_unique<RepeatedImmutablePrimitiveFieldLiteGenerator>(
+            field, messageBitIndex, context);
+    }
+  } else {
+    if (IsRealOneof(field)) {
+      switch (GetJavaType(field)) {
+        case JAVATYPE_MESSAGE:
+          return std::make_unique<ImmutableMessageOneofFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        case JAVATYPE_ENUM:
+          return std::make_unique<ImmutableEnumOneofFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        case JAVATYPE_STRING:
+          return std::make_unique<ImmutableStringOneofFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        default:
+          return std::make_unique<ImmutablePrimitiveOneofFieldLiteGenerator>(
+              field, messageBitIndex, context);
+      }
+    } else {
+      switch (GetJavaType(field)) {
+        case JAVATYPE_MESSAGE:
+          return std::make_unique<ImmutableMessageFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        case JAVATYPE_ENUM:
+          return std::make_unique<ImmutableEnumFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        case JAVATYPE_STRING:
+          return std::make_unique<ImmutableStringFieldLiteGenerator>(
+              field, messageBitIndex, context);
+        default:
+          return std::make_unique<ImmutablePrimitiveFieldLiteGenerator>(
+              field, messageBitIndex, context);
+      }
+    }
+  }
+}
+
+}  // namespace
+
+FieldGeneratorMap<ImmutableFieldLiteGenerator> MakeImmutableFieldLiteGenerators(
+    const Descriptor* descriptor, Context* context) {
+  int messageBitIndex = 0;
+  FieldGeneratorMap<ImmutableFieldLiteGenerator> field_generators(descriptor);
+  for (int i = 0; i < descriptor->field_count(); i++) {
+    const FieldDescriptor* field = descriptor->field(i);
+    auto generator =
+        CreateImmutableLiteGenerator(field, messageBitIndex, context);
+    messageBitIndex += generator->GetNumBitsForMessage();
+    field_generators.Add(field, std::move(generator));
+  }
+  return field_generators;
+}
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google

src/google/protobuf/compiler/java/lite/make_field_generators.h

@@ -0,0 +1,32 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2024 Google Inc.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_LITE_MAKE_FIELD_GENERATORS_H__
+#define GOOGLE_PROTOBUF_COMPILER_JAVA_LITE_MAKE_FIELD_GENERATORS_H__
+
+#include <memory>
+#include <vector>
+
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/generator_common.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/descriptor.h"
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace java {
+
+FieldGeneratorMap<ImmutableFieldLiteGenerator> MakeImmutableFieldLiteGenerators(
+    const Descriptor* descriptor, Context* context);
+
+}  // namespace java
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_LITE_MAKE_FIELD_GENERATORS_H__

src/google/protobuf/compiler/java/lite/map_field.cc

@@ -5,14 +5,16 @@
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd
 
-#include "google/protobuf/compiler/java/map_field_lite.h"
+#include "google/protobuf/compiler/java/lite/map_field.h"
 
 #include <cstdint>
 #include <string>
 
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
 

src/google/protobuf/compiler/java/lite/map_field.h

@@ -9,8 +9,14 @@
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_MAP_FIELD_LITE_H__
 
 #include <cstdint>
-
+#include <string>
-#include "google/protobuf/compiler/java/field.h"
+#include <vector>
+
+#include "absl/container/flat_hash_map.h"
+#include "absl/strings/string_view.h"
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/lite/message.cc

@@ -9,27 +9,32 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/message_lite.h"
+#include "google/protobuf/compiler/java/lite/message.h"
 
 #include <algorithm>
+#include <cstddef>
 #include <cstdint>
 #include <memory>
 #include <string>
+#include <utility>
 #include <vector>
 
 #include "absl/container/flat_hash_map.h"
+#include "absl/log/absl_check.h"
 #include "absl/strings/ascii.h"
 #include "absl/strings/str_cat.h"
+#include "absl/strings/string_view.h"
 #include "absl/strings/substitute.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
-#include "google/protobuf/compiler/java/enum_lite.h"
+#include "google/protobuf/compiler/java/field_common.h"
-#include "google/protobuf/compiler/java/extension_lite.h"
 #include "google/protobuf/compiler/java/generator.h"
 #include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/compiler/java/helpers.h"
-#include "google/protobuf/compiler/java/message_builder.h"
+#include "google/protobuf/compiler/java/lite/enum.h"
-#include "google/protobuf/compiler/java/message_builder_lite.h"
+#include "google/protobuf/compiler/java/lite/extension.h"
+#include "google/protobuf/compiler/java/lite/make_field_generators.h"
+#include "google/protobuf/compiler/java/lite/message_builder.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/descriptor.pb.h"
 #include "google/protobuf/io/coded_stream.h"
@@ -53,7 +58,7 @@ ImmutableMessageLiteGenerator::ImmutableMessageLiteGenerator(
     : MessageGenerator(descriptor),
       context_(context),
       name_resolver_(context->GetNameResolver()),
-      field_generators_(descriptor, context_) {
+      field_generators_(MakeImmutableFieldLiteGenerators(descriptor, context)) {
   ABSL_CHECK(!HasDescriptorMethods(descriptor->file(), context->EnforceLite()))
       << "Generator factory error: A lite message generator is used to "
          "generate non-lite messages.";

src/google/protobuf/compiler/java/lite/message.h

@@ -12,8 +12,16 @@
 #ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_MESSAGE_LITE_H__
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_MESSAGE_LITE_H__
 
-#include "google/protobuf/compiler/java/field.h"
+#include <memory>
-#include "google/protobuf/compiler/java/message.h"
+#include <vector>
+
+#include "google/protobuf/compiler/java/context.h"
+#include "google/protobuf/compiler/java/generator_common.h"
+#include "google/protobuf/compiler/java/generator_factory.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/compiler/java/name_resolver.h"
+#include "google/protobuf/descriptor.h"
+#include "google/protobuf/io/printer.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/lite/message_builder.cc

@@ -9,27 +9,21 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/message_builder_lite.h"
+#include "google/protobuf/compiler/java/lite/message_builder.h"
 
-#include <algorithm>
-#include <memory>
 #include <string>
-#include <vector>
 
 #include "absl/container/flat_hash_map.h"
 #include "absl/strings/str_cat.h"
-#include "absl/strings/substitute.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
-#include "google/protobuf/compiler/java/enum.h"
+#include "google/protobuf/compiler/java/field_common.h"
-#include "google/protobuf/compiler/java/extension.h"
-#include "google/protobuf/compiler/java/generator_factory.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/lite/enum.h"
+#include "google/protobuf/compiler/java/lite/make_field_generators.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/descriptor.pb.h"
-#include "google/protobuf/io/coded_stream.h"
 #include "google/protobuf/io/printer.h"
-#include "google/protobuf/wire_format.h"
 
 // Must be last.
 #include "google/protobuf/port_def.inc"
@@ -44,7 +38,7 @@ MessageBuilderLiteGenerator::MessageBuilderLiteGenerator(
     : descriptor_(descriptor),
       context_(context),
       name_resolver_(context->GetNameResolver()),
-      field_generators_(descriptor, context_) {
+      field_generators_(MakeImmutableFieldLiteGenerators(descriptor, context)) {
   ABSL_CHECK(!HasDescriptorMethods(descriptor->file(), context->EnforceLite()))
       << "Generator factory error: A lite message generator is used to "
          "generate non-lite messages.";

src/google/protobuf/compiler/java/lite/message_builder.h

@@ -15,7 +15,8 @@
 #include <string>
 
 #include "absl/container/btree_map.h"
-#include "google/protobuf/compiler/java/field.h"
+#include "google/protobuf/compiler/java/generator_common.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/lite/message_field.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/message_field_lite.h"
+#include "google/protobuf/compiler/java/lite/message_field.h"
 
 #include <cstdint>
 #include <string>
@@ -17,7 +17,9 @@
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/io/printer.h"
 #include "google/protobuf/wire_format.h"

src/google/protobuf/compiler/java/lite/message_field.h

@@ -14,8 +14,12 @@
 
 #include <cstdint>
 #include <string>
+#include <vector>
 
-#include "google/protobuf/compiler/java/field.h"
+#include "absl/container/flat_hash_map.h"
+#include "absl/strings/string_view.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/lite/primitive_field.cc

@@ -9,7 +9,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/primitive_field_lite.h"
+#include "google/protobuf/compiler/java/lite/primitive_field.h"
 
 #include <cstdint>
 #include <string>
@@ -19,7 +19,9 @@
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/wire_format.h"
 

src/google/protobuf/compiler/java/lite/primitive_field.h

@@ -14,8 +14,12 @@
 
 #include <cstdint>
 #include <string>
+#include <vector>
 
-#include "google/protobuf/compiler/java/field.h"
+#include "absl/container/flat_hash_map.h"
+#include "absl/strings/string_view.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/lite/string_field.cc

@@ -10,7 +10,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
-#include "google/protobuf/compiler/java/string_field_lite.h"
+#include "google/protobuf/compiler/java/lite/string_field.h"
 
 #include <cstdint>
 #include <string>
@@ -20,7 +20,9 @@
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/java/context.h"
 #include "google/protobuf/compiler/java/doc_comment.h"
+#include "google/protobuf/compiler/java/field_common.h"
 #include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/internal_helpers.h"
 #include "google/protobuf/compiler/java/name_resolver.h"
 #include "google/protobuf/wire_format.h"
 

src/google/protobuf/compiler/java/lite/string_field.h

@@ -15,8 +15,12 @@
 
 #include <cstdint>
 #include <string>
+#include <vector>
 
-#include "google/protobuf/compiler/java/field.h"
+#include "absl/container/flat_hash_map.h"
+#include "absl/strings/string_view.h"
+#include "google/protobuf/compiler/java/lite/field_generator.h"
+#include "google/protobuf/descriptor.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/java/message_serialization.h

@@ -12,8 +12,8 @@
 #include <cstddef>
 #include <vector>
 
-#include "google/protobuf/compiler/java/field.h"
+#include "absl/types/span.h"
-#include "google/protobuf/compiler/java/helpers.h"
+#include "google/protobuf/compiler/java/generator_common.h"
 #include "google/protobuf/descriptor.h"
 #include "google/protobuf/io/printer.h"
 
@@ -29,12 +29,9 @@ void GenerateSerializeExtensionRange(io::Printer* printer,
 // Generates code to serialize all fields and extension ranges for the specified
 // message descriptor, sorting serialization calls in increasing order by field
 // number.
-//
+inline void GenerateSerializeFieldsAndExtensions(
-// Templatized to support different field generator implementations.
-template <typename FieldGenerator>
-void GenerateSerializeFieldsAndExtensions(
     io::Printer* printer,
-    const FieldGeneratorMap<FieldGenerator>& field_generators,
+    const std::vector<const FieldGenerator*>& field_generators,
     const Descriptor* descriptor, const FieldDescriptor** sorted_fields) {
   std::vector<const Descriptor::ExtensionRange*> sorted_extensions;
   sorted_extensions.reserve(descriptor->extension_range_count());
@@ -62,7 +59,8 @@ void GenerateSerializeFieldsAndExtensions(
     if (range != nullptr) {
       GenerateSerializeExtensionRange(printer, range);
     }
-    field_generators.get(field).GenerateSerializationCode(printer);
+    size_t idx = static_cast<size_t>(field->index());
+    field_generators[idx]->GenerateSerializationCode(printer);
   }
 
   // After serializing all fields, serialize any remaining extensions via a