Update //third_party/protobuf to version 3.

third_party/protobuf/src/google/protobuf/compiler/java/java_string_field.cc

 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
-// http://code.google.com/p/protobuf/
+// https://developers.google.com/protocol-buffers/
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
@@ skipping 15 matching lines @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Author: kenton@google.com (Kenton Varda)
 // Author: jonp@google.com (Jon Perlow)
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
 #include <map>
 #include <string>
 
+#include <google/protobuf/stubs/logging.h>
+#include <google/protobuf/stubs/common.h>
+#include <google/protobuf/compiler/java/java_context.h>
+#include <google/protobuf/compiler/java/java_doc_comment.h>
+#include <google/protobuf/compiler/java/java_helpers.h>
+#include <google/protobuf/compiler/java/java_name_resolver.h>
 #include <google/protobuf/compiler/java/java_string_field.h>
-#include <google/protobuf/compiler/java/java_doc_comment.h>
-#include <google/protobuf/stubs/common.h>
-#include <google/protobuf/compiler/java/java_helpers.h>
 #include <google/protobuf/io/printer.h>
 #include <google/protobuf/wire_format.h>
 #include <google/protobuf/stubs/strutil.h>
 
 namespace google {
 namespace protobuf {
 namespace compiler {
 namespace java {
 
 using internal::WireFormat;
 using internal::WireFormatLite;
 
 namespace {
 
 void SetPrimitiveVariables(const FieldDescriptor* descriptor,
                            int messageBitIndex,
                            int builderBitIndex,
+                           const FieldGeneratorInfo* info,
+                           ClassNameResolver* name_resolver,
                            map<string, string>* variables) {
-  (*variables)["name"] =
-    UnderscoresToCamelCase(descriptor);
-  (*variables)["capitalized_name"] =
-    UnderscoresToCapitalizedCamelCase(descriptor);
-  (*variables)["constant_name"] = FieldConstantName(descriptor);
-  (*variables)["number"] = SimpleItoa(descriptor->number());
+  SetCommonFieldVariables(descriptor, info, variables);
+
   (*variables)["empty_list"] = "com.google.protobuf.LazyStringArrayList.EMPTY";
 
-  (*variables)["default"] = DefaultValue(descriptor);
-  (*variables)["default_init"] = ("= " + DefaultValue(descriptor));
+  (*variables)["default"] = ImmutableDefaultValue(descriptor, name_resolver);
+  (*variables)["default_init"] =
+      "= " + ImmutableDefaultValue(descriptor, name_resolver);
   (*variables)["capitalized_type"] = "String";
   (*variables)["tag"] = SimpleItoa(WireFormat::MakeTag(descriptor));
   (*variables)["tag_size"] = SimpleItoa(
       WireFormat::TagSize(descriptor->number(), GetType(descriptor)));
   (*variables)["null_check"] =
       "  if (value == null) {\n"
       "    throw new NullPointerException();\n"
       "  }\n";
+  (*variables)["writeString"] =
+      "com.google.protobuf.GeneratedMessage.writeString";
+  (*variables)["computeStringSize"] =
+      "com.google.protobuf.GeneratedMessage.computeStringSize";
 
   // TODO(birdo): Add @deprecated javadoc when generating javadoc is supported
   // by the proto compiler
   (*variables)["deprecation"] = descriptor->options().deprecated()
       ? "@java.lang.Deprecated " : "";
   (*variables)["on_changed"] =
       HasDescriptorMethods(descriptor->containing_type()) ? "onChanged();" : "";
 
-  // For singular messages and builders, one bit is used for the hasField bit.
-  (*variables)["get_has_field_bit_message"] = GenerateGetBit(messageBitIndex);
-  (*variables)["set_has_field_bit_message"] = GenerateSetBit(messageBitIndex);
+  if (SupportFieldPresence(descriptor->file())) {
+    // For singular messages and builders, one bit is used for the hasField bit.
+    (*variables)["get_has_field_bit_message"] = GenerateGetBit(messageBitIndex);
+    (*variables)["get_has_field_bit_builder"] = GenerateGetBit(builderBitIndex);
 
-  (*variables)["get_has_field_bit_builder"] = GenerateGetBit(builderBitIndex);
-  (*variables)["set_has_field_bit_builder"] = GenerateSetBit(builderBitIndex);
-  (*variables)["clear_has_field_bit_builder"] =
-      GenerateClearBit(builderBitIndex);
+    // Note that these have a trailing ";".
+    (*variables)["set_has_field_bit_message"] =
+        GenerateSetBit(messageBitIndex) + ";";
+    (*variables)["set_has_field_bit_builder"] =
+        GenerateSetBit(builderBitIndex) + ";";
+    (*variables)["clear_has_field_bit_builder"] =
+        GenerateClearBit(builderBitIndex) + ";";
 
-  // For repated builders, one bit is used for whether the array is immutable.
+    (*variables)["is_field_present_message"] = GenerateGetBit(messageBitIndex);
+  } else {
+    (*variables)["set_has_field_bit_message"] = "";
+    (*variables)["set_has_field_bit_builder"] = "";
+    (*variables)["clear_has_field_bit_builder"] = "";
+
+    (*variables)["is_field_present_message"] =
+        "!get" + (*variables)["capitalized_name"] + "Bytes().isEmpty()";
+  }
+
+  // For repeated builders, one bit is used for whether the array is immutable.
   (*variables)["get_mutable_bit_builder"] = GenerateGetBit(builderBitIndex);
   (*variables)["set_mutable_bit_builder"] = GenerateSetBit(builderBitIndex);
   (*variables)["clear_mutable_bit_builder"] = GenerateClearBit(builderBitIndex);
 
   // For repeated fields, one bit is used for whether the array is immutable
   // in the parsing constructor.
   (*variables)["get_mutable_bit_parser"] =
       GenerateGetBitMutableLocal(builderBitIndex);
   (*variables)["set_mutable_bit_parser"] =
       GenerateSetBitMutableLocal(builderBitIndex);
 
   (*variables)["get_has_field_bit_from_local"] =
       GenerateGetBitFromLocal(builderBitIndex);
   (*variables)["set_has_field_bit_to_local"] =
       GenerateSetBitToLocal(messageBitIndex);
 }
 
 }  // namespace
 
 // ===================================================================
 
-StringFieldGenerator::
-StringFieldGenerator(const FieldDescriptor* descriptor,
-                     int messageBitIndex,
-                     int builderBitIndex)
+ImmutableStringFieldGenerator::
+ImmutableStringFieldGenerator(const FieldDescriptor* descriptor,
+                              int messageBitIndex,
+                              int builderBitIndex,
+                              Context* context)
   : descriptor_(descriptor), messageBitIndex_(messageBitIndex),
-    builderBitIndex_(builderBitIndex) {
+    builderBitIndex_(builderBitIndex), context_(context),
+    name_resolver_(context->GetNameResolver()) {
   SetPrimitiveVariables(descriptor, messageBitIndex, builderBitIndex,
-                        &variables_);
+                        context->GetFieldGeneratorInfo(descriptor),
+                        name_resolver_, &variables_);
 }
 
-StringFieldGenerator::~StringFieldGenerator() {}
+ImmutableStringFieldGenerator::~ImmutableStringFieldGenerator() {}
 
-int StringFieldGenerator::GetNumBitsForMessage() const {
+int ImmutableStringFieldGenerator::GetNumBitsForMessage() const {
   return 1;
 }
 
-int StringFieldGenerator::GetNumBitsForBuilder() const {
+int ImmutableStringFieldGenerator::GetNumBitsForBuilder() const {
   return 1;
 }
 
 // A note about how strings are handled. This code used to just store a String
 // in the Message. This had two issues:
 //
 //  1. It wouldn't roundtrip byte arrays that were not vaid UTF-8 encoded
 //     strings, but rather fields that were raw bytes incorrectly marked
 //     as strings in the proto file. This is common because in the proto1
 //     syntax, string was the way to indicate bytes and C++ engineers can
@@ skipping 15 matching lines @@
 // the other, they may cause a conversion to happen more times than would
 // otherwise be necessary. This was deemed better than adding synchronization
 // overhead. It will not cause any corruption issues or affect the behavior of
 // the API. The instanceof check is also highly optimized in the JVM and we
 // decided it was better to reduce the memory overhead by not having two
 // separate fields but rather use dynamic type checking.
 //
 // For single fields, the logic for this is done inside the generated code. For
 // repeated fields, the logic is done in LazyStringArrayList and
 // UnmodifiableLazyStringList.
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateInterfaceMembers(io::Printer* printer) const {
-  WriteFieldDocComment(printer, descriptor_);
-  printer->Print(variables_,
-    "$deprecation$boolean has$capitalized_name$();\n");
+  if (SupportFieldPresence(descriptor_->file())) {
+    WriteFieldDocComment(printer, descriptor_);
+    printer->Print(variables_,
+      "$deprecation$boolean has$capitalized_name$();\n");
+  }
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$java.lang.String get$capitalized_name$();\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$com.google.protobuf.ByteString\n"
     "    get$capitalized_name$Bytes();\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateMembers(io::Printer* printer) const {
   printer->Print(variables_,
-    "private java.lang.Object $name$_;\n");
-  WriteFieldDocComment(printer, descriptor_);
-  printer->Print(variables_,
-    "$deprecation$public boolean has$capitalized_name$() {\n"
-    "  return $get_has_field_bit_message$;\n"
-    "}\n");
+    "private volatile java.lang.Object $name$_;\n");
+  PrintExtraFieldInfo(variables_, printer);
+
+  if (SupportFieldPresence(descriptor_->file())) {
+    WriteFieldDocComment(printer, descriptor_);
+    printer->Print(variables_,
+      "$deprecation$public boolean has$capitalized_name$() {\n"
+      "  return $get_has_field_bit_message$;\n"
+      "}\n");
+  }
 
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public java.lang.String get$capitalized_name$() {\n"
     "  java.lang.Object ref = $name$_;\n"
     "  if (ref instanceof java.lang.String) {\n"
     "    return (java.lang.String) ref;\n"
     "  } else {\n"
     "    com.google.protobuf.ByteString bs = \n"
     "        (com.google.protobuf.ByteString) ref;\n"
-    "    java.lang.String s = bs.toStringUtf8();\n"
-    "    if (bs.isValidUtf8()) {\n"
-    "      $name$_ = s;\n"
-    "    }\n"
+      "    java.lang.String s = bs.toStringUtf8();\n");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "    $name$_ = s;\n");
+  } else {
+    printer->Print(variables_,
+      "    if (bs.isValidUtf8()) {\n"
+      "      $name$_ = s;\n"
+      "    }\n");
+  }
+  printer->Print(variables_,
     "    return s;\n"
     "  }\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public com.google.protobuf.ByteString\n"
     "    get$capitalized_name$Bytes() {\n"
     "  java.lang.Object ref = $name$_;\n"
     "  if (ref instanceof java.lang.String) {\n"
     "    com.google.protobuf.ByteString b = \n"
     "        com.google.protobuf.ByteString.copyFromUtf8(\n"
     "            (java.lang.String) ref);\n"
     "    $name$_ = b;\n"
     "    return b;\n"
     "  } else {\n"
     "    return (com.google.protobuf.ByteString) ref;\n"
     "  }\n"
     "}\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateBuilderMembers(io::Printer* printer) const {
   printer->Print(variables_,
     "private java.lang.Object $name$_ $default_init$;\n");
-  WriteFieldDocComment(printer, descriptor_);
-  printer->Print(variables_,
-    "$deprecation$public boolean has$capitalized_name$() {\n"
-    "  return $get_has_field_bit_builder$;\n"
-    "}\n");
+  if (SupportFieldPresence(descriptor_->file())) {
+    WriteFieldDocComment(printer, descriptor_);
+    printer->Print(variables_,
+      "$deprecation$public boolean has$capitalized_name$() {\n"
+      "  return $get_has_field_bit_builder$;\n"
+      "}\n");
+  }
 
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public java.lang.String get$capitalized_name$() {\n"
     "  java.lang.Object ref = $name$_;\n"
     "  if (!(ref instanceof java.lang.String)) {\n"
-    "    java.lang.String s = ((com.google.protobuf.ByteString) ref)\n"
-    "        .toStringUtf8();\n"
-    "    $name$_ = s;\n"
+    "    com.google.protobuf.ByteString bs =\n"
+    "        (com.google.protobuf.ByteString) ref;\n"
+    "    java.lang.String s = bs.toStringUtf8();\n");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "    $name$_ = s;\n");
+  } else {
+    printer->Print(variables_,
+      "    if (bs.isValidUtf8()) {\n"
+      "      $name$_ = s;\n"
+      "    }\n");
+  }
+  printer->Print(variables_,
     "    return s;\n"
     "  } else {\n"
     "    return (java.lang.String) ref;\n"
     "  }\n"
     "}\n");
 
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public com.google.protobuf.ByteString\n"
     "    get$capitalized_name$Bytes() {\n"
     "  java.lang.Object ref = $name$_;\n"
     "  if (ref instanceof String) {\n"
     "    com.google.protobuf.ByteString b = \n"
     "        com.google.protobuf.ByteString.copyFromUtf8(\n"
     "            (java.lang.String) ref);\n"
     "    $name$_ = b;\n"
     "    return b;\n"
     "  } else {\n"
     "    return (com.google.protobuf.ByteString) ref;\n"
     "  }\n"
     "}\n");
 
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public Builder set$capitalized_name$(\n"
     "    java.lang.String value) {\n"
     "$null_check$"
-    "  $set_has_field_bit_builder$;\n"
+    "  $set_has_field_bit_builder$\n"
     "  $name$_ = value;\n"
     "  $on_changed$\n"
     "  return this;\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public Builder clear$capitalized_name$() {\n"
-    "  $clear_has_field_bit_builder$;\n");
+    "  $clear_has_field_bit_builder$\n");
   // The default value is not a simple literal so we want to avoid executing
   // it multiple times.  Instead, get the default out of the default instance.
   printer->Print(variables_,
     "  $name$_ = getDefaultInstance().get$capitalized_name$();\n");
   printer->Print(variables_,
     "  $on_changed$\n"
     "  return this;\n"
     "}\n");
 
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public Builder set$capitalized_name$Bytes(\n"
     "    com.google.protobuf.ByteString value) {\n"
-    "$null_check$"
-    "  $set_has_field_bit_builder$;\n"
+    "$null_check$");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "  checkByteStringIsUtf8(value);\n");
+  }
+  printer->Print(variables_,
+    "  $set_has_field_bit_builder$\n"
     "  $name$_ = value;\n"
     "  $on_changed$\n"
     "  return this;\n"
     "}\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateFieldBuilderInitializationCode(io::Printer* printer)  const {
   // noop for primitives
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateInitializationCode(io::Printer* printer) const {
   printer->Print(variables_, "$name$_ = $default$;\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateBuilderClearCode(io::Printer* printer) const {
   printer->Print(variables_,
     "$name$_ = $default$;\n"
-    "$clear_has_field_bit_builder$;\n");
+    "$clear_has_field_bit_builder$\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
-  // Allow a slight breach of abstraction here in order to avoid forcing
-  // all string fields to Strings when copying fields from a Message.
-  printer->Print(variables_,
-    "if (other.has$capitalized_name$()) {\n"
-    "  $set_has_field_bit_builder$;\n"
-    "  $name$_ = other.$name$_;\n"
-    "  $on_changed$\n"
-    "}\n");
+  if (SupportFieldPresence(descriptor_->file())) {
+    // Allow a slight breach of abstraction here in order to avoid forcing
+    // all string fields to Strings when copying fields from a Message.
+    printer->Print(variables_,
+      "if (other.has$capitalized_name$()) {\n"
+      "  $set_has_field_bit_builder$\n"
+      "  $name$_ = other.$name$_;\n"
+      "  $on_changed$\n"
+      "}\n");
+  } else {
+    printer->Print(variables_,
+      "if (!other.get$capitalized_name$().isEmpty()) {\n"
+      "  $name$_ = other.$name$_;\n"
+      "  $on_changed$\n"
+      "}\n");
+  }
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateBuildingCode(io::Printer* printer) const {
+  if (SupportFieldPresence(descriptor_->file())) {
+    printer->Print(variables_,
+      "if ($get_has_field_bit_from_local$) {\n"
+      "  $set_has_field_bit_to_local$;\n"
+      "}\n");
+  }
   printer->Print(variables_,
-    "if ($get_has_field_bit_from_local$) {\n"
-    "  $set_has_field_bit_to_local$;\n"
-    "}\n"
     "result.$name$_ = $name$_;\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateParsingCode(io::Printer* printer) const {
-  printer->Print(variables_,
-    "$set_has_field_bit_message$;\n"
-    "$name$_ = input.readBytes();\n");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "java.lang.String s = input.readStringRequireUtf8();\n"
+      "$set_has_field_bit_message$\n"
+      "$name$_ = s;\n");
+  } else if (!HasDescriptorMethods(descriptor_->file())) {
+    // Lite runtime should attempt to reduce allocations by attempting to
+    // construct the string directly from the input stream buffer. This avoids
+    // spurious intermediary ByteString allocations, cutting overall allocations
+    // in half.
+    printer->Print(variables_,
+      "java.lang.String s = input.readString();\n"
+      "$set_has_field_bit_message$\n"
+      "$name$_ = s;\n");
+  } else {
+    printer->Print(variables_,
+      "com.google.protobuf.ByteString bs = input.readBytes();\n"
+      "$set_has_field_bit_message$\n"
+      "$name$_ = bs;\n");
+  }
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateParsingDoneCode(io::Printer* printer) const {
   // noop for strings.
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateSerializationCode(io::Printer* printer) const {
   printer->Print(variables_,
-    "if ($get_has_field_bit_message$) {\n"
-    "  output.writeBytes($number$, get$capitalized_name$Bytes());\n"
+    "if ($is_field_present_message$) {\n"
+    "  $writeString$(output, $number$, $name$_);\n"
     "}\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateSerializedSizeCode(io::Printer* printer) const {
   printer->Print(variables_,
-    "if ($get_has_field_bit_message$) {\n"
-    "  size += com.google.protobuf.CodedOutputStream\n"
-    "    .computeBytesSize($number$, get$capitalized_name$Bytes());\n"
+    "if ($is_field_present_message$) {\n"
+    "  size += $computeStringSize$($number$, $name$_);\n"
     "}\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateEqualsCode(io::Printer* printer) const {
   printer->Print(variables_,
     "result = result && get$capitalized_name$()\n"
     "    .equals(other.get$capitalized_name$());\n");
 }
 
-void StringFieldGenerator::
+void ImmutableStringFieldGenerator::
 GenerateHashCode(io::Printer* printer) const {
   printer->Print(variables_,
     "hash = (37 * hash) + $constant_name$;\n");
   printer->Print(variables_,
     "hash = (53 * hash) + get$capitalized_name$().hashCode();\n");
 }
 
-string StringFieldGenerator::GetBoxedType() const {
+string ImmutableStringFieldGenerator::GetBoxedType() const {
   return "java.lang.String";
 }
 
-
 // ===================================================================
 
-RepeatedStringFieldGenerator::
-RepeatedStringFieldGenerator(const FieldDescriptor* descriptor,
-                             int messageBitIndex,
-                             int builderBitIndex)
+ImmutableStringOneofFieldGenerator::
+ImmutableStringOneofFieldGenerator(const FieldDescriptor* descriptor,
+                                   int messageBitIndex,
+                                   int builderBitIndex,
+                                   Context* context)
+    : ImmutableStringFieldGenerator(
+          descriptor, messageBitIndex, builderBitIndex, context) {
+  const OneofGeneratorInfo* info =
+      context->GetOneofGeneratorInfo(descriptor->containing_oneof());
+  SetCommonOneofVariables(descriptor, info, &variables_);
+}
+
+ImmutableStringOneofFieldGenerator::
+~ImmutableStringOneofFieldGenerator() {}
+
+void ImmutableStringOneofFieldGenerator::
+GenerateMembers(io::Printer* printer) const {
+  PrintExtraFieldInfo(variables_, printer);
+
+  if (SupportFieldPresence(descriptor_->file())) {
+  WriteFieldDocComment(printer, descriptor_);
+  printer->Print(variables_,
+    "$deprecation$public boolean has$capitalized_name$() {\n"
+    "  return $has_oneof_case_message$;\n"
+    "}\n");
+  }
+
+  WriteFieldDocComment(printer, descriptor_);
+  printer->Print(variables_,
+    "$deprecation$public java.lang.String get$capitalized_name$() {\n"
+    "  java.lang.Object ref $default_init$;\n"
+    "  if ($has_oneof_case_message$) {\n"
+    "    ref = $oneof_name$_;\n"
+    "  }\n"
+    "  if (ref instanceof java.lang.String) {\n"
+    "    return (java.lang.String) ref;\n"
+    "  } else {\n"
+    "    com.google.protobuf.ByteString bs = \n"
+    "        (com.google.protobuf.ByteString) ref;\n"
+    "    java.lang.String s = bs.toStringUtf8();\n");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+    "    if ($has_oneof_case_message$) {\n"
+    "      $oneof_name$_ = s;\n"
+    "    }\n");
+  } else {
+    printer->Print(variables_,
+    "    if (bs.isValidUtf8() && ($has_oneof_case_message$)) {\n"
+    "      $oneof_name$_ = s;\n"
+    "    }\n");
+  }
+  printer->Print(variables_,
+    "    return s;\n"
+    "  }\n"
+    "}\n");
+  WriteFieldDocComment(printer, descriptor_);
+
+  printer->Print(variables_,
+    "$deprecation$public com.google.protobuf.ByteString\n"
+    "    get$capitalized_name$Bytes() {\n"
+    "  java.lang.Object ref $default_init$;\n"
+    "  if ($has_oneof_case_message$) {\n"
+    "    ref = $oneof_name$_;\n"
+    "  }\n"
+    "  if (ref instanceof java.lang.String) {\n"
+    "    com.google.protobuf.ByteString b = \n"
+    "        com.google.protobuf.ByteString.copyFromUtf8(\n"
+    "            (java.lang.String) ref);\n"
+    "    if ($has_oneof_case_message$) {\n"
+    "      $oneof_name$_ = b;\n"
+    "    }\n"
+    "    return b;\n"
+    "  } else {\n"
+    "    return (com.google.protobuf.ByteString) ref;\n"
+    "  }\n"
+    "}\n");
+}
+
+void ImmutableStringOneofFieldGenerator::
+GenerateBuilderMembers(io::Printer* printer) const {
+  if (SupportFieldPresence(descriptor_->file())) {
+    WriteFieldDocComment(printer, descriptor_);
+    printer->Print(variables_,
+      "$deprecation$public boolean has$capitalized_name$() {\n"
+      "  return $has_oneof_case_message$;\n"
+      "}\n");
+  }
+
+  WriteFieldDocComment(printer, descriptor_);
+  printer->Print(variables_,
+    "$deprecation$public java.lang.String get$capitalized_name$() {\n"
+    "  java.lang.Object ref $default_init$;\n"
+    "  if ($has_oneof_case_message$) {\n"
+    "    ref = $oneof_name$_;\n"
+    "  }\n"
+    "  if (!(ref instanceof java.lang.String)) {\n"
+    "    com.google.protobuf.ByteString bs =\n"
+    "        (com.google.protobuf.ByteString) ref;\n"
+    "    java.lang.String s = bs.toStringUtf8();\n"
+    "    if ($has_oneof_case_message$) {\n");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "      $oneof_name$_ = s;\n");
+  } else {
+    printer->Print(variables_,
+      "      if (bs.isValidUtf8()) {\n"
+      "        $oneof_name$_ = s;\n"
+      "      }\n");
+  }
+  printer->Print(variables_,
+    "    }\n"
+    "    return s;\n"
+    "  } else {\n"
+    "    return (java.lang.String) ref;\n"
+    "  }\n"
+    "}\n");
+
+  WriteFieldDocComment(printer, descriptor_);
+  printer->Print(variables_,
+    "$deprecation$public com.google.protobuf.ByteString\n"
+    "    get$capitalized_name$Bytes() {\n"
+    "  java.lang.Object ref $default_init$;\n"
+    "  if ($has_oneof_case_message$) {\n"
+    "    ref = $oneof_name$_;\n"
+    "  }\n"
+    "  if (ref instanceof String) {\n"
+    "    com.google.protobuf.ByteString b = \n"
+    "        com.google.protobuf.ByteString.copyFromUtf8(\n"
+    "            (java.lang.String) ref);\n"
+    "    if ($has_oneof_case_message$) {\n"
+    "      $oneof_name$_ = b;\n"
+    "    }\n"
+    "    return b;\n"
+    "  } else {\n"
+    "    return (com.google.protobuf.ByteString) ref;\n"
+    "  }\n"
+    "}\n");
+
+  WriteFieldDocComment(printer, descriptor_);
+  printer->Print(variables_,
+    "$deprecation$public Builder set$capitalized_name$(\n"
+    "    java.lang.String value) {\n"
+    "$null_check$"
+    "  $set_oneof_case_message$;\n"
+    "  $oneof_name$_ = value;\n"
+    "  $on_changed$\n"
+    "  return this;\n"
+    "}\n");
+  WriteFieldDocComment(printer, descriptor_);
+  printer->Print(variables_,
+    "$deprecation$public Builder clear$capitalized_name$() {\n"
+    "  if ($has_oneof_case_message$) {\n"
+    "    $clear_oneof_case_message$;\n"
+    "    $oneof_name$_ = null;\n"
+    "    $on_changed$\n"
+    "  }\n"
+    "  return this;\n"
+    "}\n");
+
+  WriteFieldDocComment(printer, descriptor_);
+  printer->Print(variables_,
+    "$deprecation$public Builder set$capitalized_name$Bytes(\n"
+    "    com.google.protobuf.ByteString value) {\n"
+    "$null_check$");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "  checkByteStringIsUtf8(value);\n");
+  }
+  printer->Print(variables_,
+    "  $set_oneof_case_message$;\n"
+    "  $oneof_name$_ = value;\n"
+    "  $on_changed$\n"
+    "  return this;\n"
+    "}\n");
+}
+
+void ImmutableStringOneofFieldGenerator::
+GenerateMergingCode(io::Printer* printer) const {
+  // Allow a slight breach of abstraction here in order to avoid forcing
+  // all string fields to Strings when copying fields from a Message.
+  printer->Print(variables_,
+    "$set_oneof_case_message$;\n"
+    "$oneof_name$_ = other.$oneof_name$_;\n"
+    "$on_changed$\n");
+}
+
+void ImmutableStringOneofFieldGenerator::
+GenerateBuildingCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if ($has_oneof_case_message$) {\n"
+    "  result.$oneof_name$_ = $oneof_name$_;\n"
+    "}\n");
+}
+
+void ImmutableStringOneofFieldGenerator::
+GenerateParsingCode(io::Printer* printer) const {
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "java.lang.String s = input.readStringRequireUtf8();\n"
+      "$set_oneof_case_message$;\n"
+      "$oneof_name$_ = s;\n");
+  } else if (!HasDescriptorMethods(descriptor_->file())) {
+    // Lite runtime should attempt to reduce allocations by attempting to
+    // construct the string directly from the input stream buffer. This avoids
+    // spurious intermediary ByteString allocations, cutting overall allocations
+    // in half.
+    printer->Print(variables_,
+      "java.lang.String s = input.readString();\n"
+      "$set_oneof_case_message$;\n"
+      "$oneof_name$_ = s;\n");
+  } else {
+    printer->Print(variables_,
+      "com.google.protobuf.ByteString bs = input.readBytes();\n"
+      "$set_oneof_case_message$;\n"
+      "$oneof_name$_ = bs;\n");
+  }
+}
+
+void ImmutableStringOneofFieldGenerator::
+GenerateSerializationCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if ($has_oneof_case_message$) {\n"
+    "  $writeString$(output, $number$, $oneof_name$_);\n"
+    "}\n");
+}
+
+void ImmutableStringOneofFieldGenerator::
+GenerateSerializedSizeCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if ($has_oneof_case_message$) {\n"
+    "  size += $computeStringSize$($number$, $oneof_name$_);\n"
+    "}\n");
+}
+
+// ===================================================================
+
+RepeatedImmutableStringFieldGenerator::
+RepeatedImmutableStringFieldGenerator(const FieldDescriptor* descriptor,
+                                      int messageBitIndex,
+                                      int builderBitIndex,
+                                      Context* context)
   : descriptor_(descriptor), messageBitIndex_(messageBitIndex),
-    builderBitIndex_(builderBitIndex) {
+    builderBitIndex_(builderBitIndex), context_(context),
+    name_resolver_(context->GetNameResolver()) {
   SetPrimitiveVariables(descriptor, messageBitIndex, builderBitIndex,
-                        &variables_);
-}
-
-RepeatedStringFieldGenerator::~RepeatedStringFieldGenerator() {}
-
-int RepeatedStringFieldGenerator::GetNumBitsForMessage() const {
+                        context->GetFieldGeneratorInfo(descriptor),
+                        name_resolver_, &variables_);
+}
+
+RepeatedImmutableStringFieldGenerator::
+~RepeatedImmutableStringFieldGenerator() {}
+
+int RepeatedImmutableStringFieldGenerator::GetNumBitsForMessage() const {
   return 0;
 }
 
-int RepeatedStringFieldGenerator::GetNumBitsForBuilder() const {
+int RepeatedImmutableStringFieldGenerator::GetNumBitsForBuilder() const {
   return 1;
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateInterfaceMembers(io::Printer* printer) const {
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
-    "$deprecation$java.util.List<java.lang.String>\n"
-    "get$capitalized_name$List();\n");
+    "$deprecation$com.google.protobuf.ProtocolStringList\n"
+    "    get$capitalized_name$List();\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$int get$capitalized_name$Count();\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$java.lang.String get$capitalized_name$(int index);\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$com.google.protobuf.ByteString\n"
     "    get$capitalized_name$Bytes(int index);\n");
 }
 
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateMembers(io::Printer* printer) const {
   printer->Print(variables_,
     "private com.google.protobuf.LazyStringList $name$_;\n");
+  PrintExtraFieldInfo(variables_, printer);
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
-    "$deprecation$public java.util.List<java.lang.String>\n"
+    "$deprecation$public com.google.protobuf.ProtocolStringList\n"
     "    get$capitalized_name$List() {\n"
     "  return $name$_;\n"   // note:  unmodifiable list
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public int get$capitalized_name$Count() {\n"
     "  return $name$_.size();\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public java.lang.String get$capitalized_name$(int index) {\n"
     "  return $name$_.get(index);\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public com.google.protobuf.ByteString\n"
     "    get$capitalized_name$Bytes(int index) {\n"
     "  return $name$_.getByteString(index);\n"
     "}\n");
-
-  if (descriptor_->options().packed() &&
-      HasGeneratedMethods(descriptor_->containing_type())) {
-    printer->Print(variables_,
-      "private int $name$MemoizedSerializedSize = -1;\n");
-  }
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateBuilderMembers(io::Printer* printer) const {
   // One field is the list and the bit field keeps track of whether the
   // list is immutable. If it's immutable, the invariant is that it must
   // either an instance of Collections.emptyList() or it's an ArrayList
   // wrapped in a Collections.unmodifiableList() wrapper and nobody else has
   // a refererence to the underlying ArrayList. This invariant allows us to
   // share instances of lists between protocol buffers avoiding expensive
   // memory allocations. Note, immutable is a strong guarantee here -- not
   // just that the list cannot be modified via the reference but that the
   // list can never be modified.
   printer->Print(variables_,
     "private com.google.protobuf.LazyStringList $name$_ = $empty_list$;\n");
 
   printer->Print(variables_,
     "private void ensure$capitalized_name$IsMutable() {\n"
     "  if (!$get_mutable_bit_builder$) {\n"
     "    $name$_ = new com.google.protobuf.LazyStringArrayList($name$_);\n"
     "    $set_mutable_bit_builder$;\n"
     "   }\n"
     "}\n");
 
     // Note:  We return an unmodifiable list because otherwise the caller
     //   could hold on to the returned list and modify it after the message
     //   has been built, thus mutating the message which is supposed to be
     //   immutable.
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
-    "$deprecation$public java.util.List<java.lang.String>\n"
+    "$deprecation$public com.google.protobuf.ProtocolStringList\n"
     "    get$capitalized_name$List() {\n"
-    "  return java.util.Collections.unmodifiableList($name$_);\n"
+    "  return $name$_.getUnmodifiableView();\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public int get$capitalized_name$Count() {\n"
     "  return $name$_.size();\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public java.lang.String get$capitalized_name$(int index) {\n"
     "  return $name$_.get(index);\n"
@@ skipping 22 matching lines @@
     "  ensure$capitalized_name$IsMutable();\n"
     "  $name$_.add(value);\n"
     "  $on_changed$\n"
     "  return this;\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public Builder addAll$capitalized_name$(\n"
     "    java.lang.Iterable<java.lang.String> values) {\n"
     "  ensure$capitalized_name$IsMutable();\n"
-    "  super.addAll(values, $name$_);\n"
+    "  com.google.protobuf.AbstractMessageLite.Builder.addAll(\n"
+    "      values, $name$_);\n"
     "  $on_changed$\n"
     "  return this;\n"
     "}\n");
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public Builder clear$capitalized_name$() {\n"
     "  $name$_ = $empty_list$;\n"
     "  $clear_mutable_bit_builder$;\n"
     "  $on_changed$\n"
     "  return this;\n"
     "}\n");
 
   WriteFieldDocComment(printer, descriptor_);
   printer->Print(variables_,
     "$deprecation$public Builder add$capitalized_name$Bytes(\n"
     "    com.google.protobuf.ByteString value) {\n"
-    "$null_check$"
+    "$null_check$");
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+      "  checkByteStringIsUtf8(value);\n");
+  }
+  printer->Print(variables_,
     "  ensure$capitalized_name$IsMutable();\n"
     "  $name$_.add(value);\n"
     "  $on_changed$\n"
     "  return this;\n"
     "}\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateFieldBuilderInitializationCode(io::Printer* printer)  const {
   // noop for primitives
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateInitializationCode(io::Printer* printer) const {
   printer->Print(variables_, "$name$_ = $empty_list$;\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateBuilderClearCode(io::Printer* printer) const {
   printer->Print(variables_,
     "$name$_ = $empty_list$;\n"
     "$clear_mutable_bit_builder$;\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
   // The code below does two optimizations:
   //   1. If the other list is empty, there's nothing to do. This ensures we
   //      don't allocate a new array if we already have an immutable one.
   //   2. If the other list is non-empty and our current list is empty, we can
   //      reuse the other list which is guaranteed to be immutable.
   printer->Print(variables_,
     "if (!other.$name$_.isEmpty()) {\n"
     "  if ($name$_.isEmpty()) {\n"
     "    $name$_ = other.$name$_;\n"
     "    $clear_mutable_bit_builder$;\n"
     "  } else {\n"
     "    ensure$capitalized_name$IsMutable();\n"
     "    $name$_.addAll(other.$name$_);\n"
     "  }\n"
     "  $on_changed$\n"
     "}\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateBuildingCode(io::Printer* printer) const {
   // The code below ensures that the result has an immutable list. If our
   // list is immutable, we can just reuse it. If not, we make it immutable.
 
   printer->Print(variables_,
     "if ($get_mutable_bit_builder$) {\n"
-    "  $name$_ = new com.google.protobuf.UnmodifiableLazyStringList(\n"
-    "      $name$_);\n"
+    "  $name$_ = $name$_.getUnmodifiableView();\n"
     "  $clear_mutable_bit_builder$;\n"
     "}\n"
     "result.$name$_ = $name$_;\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateParsingCode(io::Printer* printer) const {
+  if (CheckUtf8(descriptor_)) {
+    printer->Print(variables_,
+    "java.lang.String s = input.readStringRequireUtf8();\n");
+  } else if (!HasDescriptorMethods(descriptor_->file())) {
+    // Lite runtime should attempt to reduce allocations by attempting to
+    // construct the string directly from the input stream buffer. This avoids
+    // spurious intermediary ByteString allocations, cutting overall allocations
+    // in half.
+    printer->Print(variables_,
+    "java.lang.String s = input.readString();\n");
+  } else {
+    printer->Print(variables_,
+    "com.google.protobuf.ByteString bs = input.readBytes();\n");
+  }
   printer->Print(variables_,
     "if (!$get_mutable_bit_parser$) {\n"
     "  $name$_ = new com.google.protobuf.LazyStringArrayList();\n"
     "  $set_mutable_bit_parser$;\n"
-    "}\n"
-    "$name$_.add(input.readBytes());\n");
+    "}\n");
+  if (CheckUtf8(descriptor_) || !HasDescriptorMethods(descriptor_->file())) {
+    printer->Print(variables_,
+      "$name$_.add(s);\n");
+  } else {
+    printer->Print(variables_,
+      "$name$_.add(bs);\n");
+  }
 }
 
-void RepeatedStringFieldGenerator::
-GenerateParsingCodeFromPacked(io::Printer* printer) const {
-  printer->Print(variables_,
-    "int length = input.readRawVarint32();\n"
-    "int limit = input.pushLimit(length);\n"
-    "if (!$get_mutable_bit_parser$ && input.getBytesUntilLimit() > 0) {\n"
-    "  $name$_ = new com.google.protobuf.LazyStringArrayList();\n"
-    "  $set_mutable_bit_parser$;\n"
-    "}\n"
-    "while (input.getBytesUntilLimit() > 0) {\n"
-    "  $name$.add(input.read$capitalized_type$());\n"
-    "}\n"
-    "input.popLimit(limit);\n");
-}
-
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateParsingDoneCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if ($get_mutable_bit_parser$) {\n"
-    "  $name$_ = new com.google.protobuf.UnmodifiableLazyStringList($name$_);\n"
+    "  $name$_ = $name$_.getUnmodifiableView();\n"
     "}\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateSerializationCode(io::Printer* printer) const {
-  if (descriptor_->options().packed()) {
-    printer->Print(variables_,
-      "if (get$capitalized_name$List().size() > 0) {\n"
-      "  output.writeRawVarint32($tag$);\n"
-      "  output.writeRawVarint32($name$MemoizedSerializedSize);\n"
-      "}\n"
-      "for (int i = 0; i < $name$_.size(); i++) {\n"
-      "  output.write$capitalized_type$NoTag($name$_.get(i));\n"
-      "}\n");
-  } else {
-    printer->Print(variables_,
-      "for (int i = 0; i < $name$_.size(); i++) {\n"
-      "  output.writeBytes($number$, $name$_.getByteString(i));\n"
-      "}\n");
-  }
+  printer->Print(variables_,
+    "for (int i = 0; i < $name$_.size(); i++) {\n"
+    "  $writeString$(output, $number$, $name$_.getRaw(i));\n"
+    "}\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateSerializedSizeCode(io::Printer* printer) const {
   printer->Print(variables_,
     "{\n"
     "  int dataSize = 0;\n");
   printer->Indent();
 
   printer->Print(variables_,
     "for (int i = 0; i < $name$_.size(); i++) {\n"
-    "  dataSize += com.google.protobuf.CodedOutputStream\n"
-    "    .computeBytesSizeNoTag($name$_.getByteString(i));\n"
+    "  dataSize += computeStringSizeNoTag($name$_.getRaw(i));\n"
     "}\n");
 
   printer->Print(
       "size += dataSize;\n");
 
-  if (descriptor_->options().packed()) {
-    printer->Print(variables_,
-      "if (!get$capitalized_name$List().isEmpty()) {\n"
-      "  size += $tag_size$;\n"
-      "  size += com.google.protobuf.CodedOutputStream\n"
-      "      .computeInt32SizeNoTag(dataSize);\n"
-      "}\n");
-  } else {
-    printer->Print(variables_,
-      "size += $tag_size$ * get$capitalized_name$List().size();\n");
-  }
-
-  // cache the data size for packed fields.
-  if (descriptor_->options().packed()) {
-    printer->Print(variables_,
-      "$name$MemoizedSerializedSize = dataSize;\n");
-  }
+  printer->Print(variables_,
+    "size += $tag_size$ * get$capitalized_name$List().size();\n");
 
   printer->Outdent();
   printer->Print("}\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateEqualsCode(io::Printer* printer) const {
   printer->Print(variables_,
     "result = result && get$capitalized_name$List()\n"
     "    .equals(other.get$capitalized_name$List());\n");
 }
 
-void RepeatedStringFieldGenerator::
+void RepeatedImmutableStringFieldGenerator::
 GenerateHashCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if (get$capitalized_name$Count() > 0) {\n"
     "  hash = (37 * hash) + $constant_name$;\n"
     "  hash = (53 * hash) + get$capitalized_name$List().hashCode();\n"
     "}\n");
 }
 
-string RepeatedStringFieldGenerator::GetBoxedType() const {
+string RepeatedImmutableStringFieldGenerator::GetBoxedType() const {
   return "String";
 }
 
 }  // namespace java
 }  // namespace compiler
 }  // namespace protobuf
 }  // namespace google