Massive roll-up of changes. See CHANGES.txt.

16 files changed, 242 insertions, 86 deletions

diff --git a/src/google/protobuf/compiler/java/java_enum.cc b/src/google/protobuf/compiler/java/java_enum.cc
index 8ade50c9..85e39f53 100644
--- a/src/google/protobuf/compiler/java/java_enum.cc
+++ b/src/google/protobuf/compiler/java/java_enum.cc
@@ -223,6 +223,11 @@ void EnumGenerator::Generate(io::Printer* printer) {
       "file", ClassName(descriptor_->file()));
   }
 
+  printer->Print(
+    "\n"
+    "// @@protoc_insertion_point(enum_scope:$full_name$)\n",
+    "full_name", descriptor_->full_name());
+
   printer->Outdent();
   printer->Print("}\n\n");
 }
diff --git a/src/google/protobuf/compiler/java/java_enum_field.cc b/src/google/protobuf/compiler/java/java_enum_field.cc
index dc36e06e..af6b1cd2 100644
--- a/src/google/protobuf/compiler/java/java_enum_field.cc
+++ b/src/google/protobuf/compiler/java/java_enum_field.cc
@@ -62,7 +62,7 @@ void SetEnumVariables(const FieldDescriptor* descriptor,
   (*variables)["default"] = DefaultValue(descriptor);
   (*variables)["tag"] = SimpleItoa(internal::WireFormat::MakeTag(descriptor));
   (*variables)["tag_size"] = SimpleItoa(
-      internal::WireFormat::TagSize(descriptor->number(), descriptor->type()));
+      internal::WireFormat::TagSize(descriptor->number(), GetType(descriptor)));
 }
 
 }  // namespace
@@ -81,7 +81,7 @@ void EnumFieldGenerator::
 GenerateMembers(io::Printer* printer) const {
   printer->Print(variables_,
     "private boolean has$capitalized_name$;\n"
-    "private $type$ $name$_ = $default$;\n"
+    "private $type$ $name$_;\n"
     "public boolean has$capitalized_name$() { return has$capitalized_name$; }\n"
     "public $type$ get$capitalized_name$() { return $name$_; }\n");
 }
@@ -111,6 +111,11 @@ GenerateBuilderMembers(io::Printer* printer) const {
 }
 
 void EnumFieldGenerator::
+GenerateInitializationCode(io::Printer* printer) const {
+  printer->Print(variables_, "$name$_ = $default$;\n");
+}
+
+void EnumFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if (other.has$capitalized_name$()) {\n"
@@ -241,6 +246,11 @@ GenerateBuilderMembers(io::Printer* printer) const {
 }
 
 void RepeatedEnumFieldGenerator::
+GenerateInitializationCode(io::Printer* printer) const {
+  // Initialized inline.
+}
+
+void RepeatedEnumFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if (!other.$name$_.isEmpty()) {\n"
@@ -262,15 +272,6 @@ GenerateBuildingCode(io::Printer* printer) const {
 
 void RepeatedEnumFieldGenerator::
 GenerateParsingCode(io::Printer* printer) const {
-  // If packed, set up the while loop
-  if (descriptor_->options().packed()) {
-    printer->Print(variables_,
-      "int length = input.readRawVarint32();\n"
-      "int oldLimit = input.pushLimit(length);\n"
-      "while(input.getBytesUntilLimit() > 0) {\n");
-    printer->Indent();
-  }
-
   // Read and store the enum
   printer->Print(variables_,
     "int rawValue = input.readEnum();\n"
@@ -287,13 +288,24 @@ GenerateParsingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "  add$capitalized_name$(value);\n"
     "}\n");
+}
 
-  if (descriptor_->options().packed()) {
-    printer->Outdent();
-    printer->Print(variables_,
-      "}\n"
-      "input.popLimit(oldLimit);\n");
-  }
+void RepeatedEnumFieldGenerator::
+GenerateParsingCodeFromPacked(io::Printer* printer) const {
+  // Wrap GenerateParsingCode's contents with a while loop.
+
+  printer->Print(variables_,
+    "int length = input.readRawVarint32();\n"
+    "int oldLimit = input.pushLimit(length);\n"
+    "while(input.getBytesUntilLimit() > 0) {\n");
+  printer->Indent();
+
+  GenerateParsingCode(printer);
+
+  printer->Outdent();
+  printer->Print(variables_,
+    "}\n"
+    "input.popLimit(oldLimit);\n");
 }
 
 void RepeatedEnumFieldGenerator::
diff --git a/src/google/protobuf/compiler/java/java_enum_field.h b/src/google/protobuf/compiler/java/java_enum_field.h
index 63f68153..c54a0faf 100644
--- a/src/google/protobuf/compiler/java/java_enum_field.h
+++ b/src/google/protobuf/compiler/java/java_enum_field.h
@@ -52,6 +52,7 @@ class EnumFieldGenerator : public FieldGenerator {
   // implements FieldGenerator ---------------------------------------
   void GenerateMembers(io::Printer* printer) const;
   void GenerateBuilderMembers(io::Printer* printer) const;
+  void GenerateInitializationCode(io::Printer* printer) const;
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateBuildingCode(io::Printer* printer) const;
   void GenerateParsingCode(io::Printer* printer) const;
@@ -75,9 +76,11 @@ class RepeatedEnumFieldGenerator : public FieldGenerator {
   // implements FieldGenerator ---------------------------------------
   void GenerateMembers(io::Printer* printer) const;
   void GenerateBuilderMembers(io::Printer* printer) const;
+  void GenerateInitializationCode(io::Printer* printer) const;
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateBuildingCode(io::Printer* printer) const;
   void GenerateParsingCode(io::Printer* printer) const;
+  void GenerateParsingCodeFromPacked(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
 
diff --git a/src/google/protobuf/compiler/java/java_extension.cc b/src/google/protobuf/compiler/java/java_extension.cc
index 4403220b..5932433f 100644
--- a/src/google/protobuf/compiler/java/java_extension.cc
+++ b/src/google/protobuf/compiler/java/java_extension.cc
@@ -133,7 +133,7 @@ void ExtensionGenerator::GenerateInitializationCode(io::Printer* printer) {
   vars["extendee"] = ClassName(descriptor_->containing_type());
   vars["default"] = descriptor_->is_repeated() ? "" : DefaultValue(descriptor_);
   vars["number"] = SimpleItoa(descriptor_->number());
-  vars["type_constant"] = TypeName(descriptor_->type());
+  vars["type_constant"] = TypeName(GetType(descriptor_));
   vars["packed"] = descriptor_->options().packed() ? "true" : "false";
   vars["enum_map"] = "null";
   vars["prototype"] = "null";
@@ -208,5 +208,4 @@ void ExtensionGenerator::GenerateRegistrationCode(io::Printer* printer) {
 }  // namespace java
 }  // namespace compiler
 }  // namespace protobuf
-
 }  // namespace google
diff --git a/src/google/protobuf/compiler/java/java_field.cc b/src/google/protobuf/compiler/java/java_field.cc
index f9d34ad7..978c8f33 100644
--- a/src/google/protobuf/compiler/java/java_field.cc
+++ b/src/google/protobuf/compiler/java/java_field.cc
@@ -46,6 +46,16 @@ namespace java {
 
 FieldGenerator::~FieldGenerator() {}
 
+void FieldGenerator::GenerateParsingCodeFromPacked(io::Printer* printer) const {
+  // 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.
+  GOOGLE_LOG(FATAL) << "GenerateParsingCodeFromPacked() "
+             << "called on field generator that does not support packing.";
+}
+
 FieldGeneratorMap::FieldGeneratorMap(const Descriptor* descriptor)
   : descriptor_(descriptor),
     field_generators_(
diff --git a/src/google/protobuf/compiler/java/java_field.h b/src/google/protobuf/compiler/java/java_field.h
index cab463c8..f5bef7ab 100644
--- a/src/google/protobuf/compiler/java/java_field.h
+++ b/src/google/protobuf/compiler/java/java_field.h
@@ -57,9 +57,11 @@ class FieldGenerator {
 
   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 GenerateMergingCode(io::Printer* printer) const = 0;
   virtual void GenerateBuildingCode(io::Printer* printer) const = 0;
   virtual void GenerateParsingCode(io::Printer* printer) const = 0;
+  virtual void GenerateParsingCodeFromPacked(io::Printer* printer) const;
   virtual void GenerateSerializationCode(io::Printer* printer) const = 0;
   virtual void GenerateSerializedSizeCode(io::Printer* printer) const = 0;
 
diff --git a/src/google/protobuf/compiler/java/java_file.cc b/src/google/protobuf/compiler/java/java_file.cc
index 2aedde5e..7ea127c0 100644
--- a/src/google/protobuf/compiler/java/java_file.cc
+++ b/src/google/protobuf/compiler/java/java_file.cc
@@ -64,7 +64,7 @@ bool UsesExtensions(const Message& message) {
   for (int i = 0; i < fields.size(); i++) {
     if (fields[i]->is_extension()) return true;
 
-    if (fields[i]->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
+    if (GetJavaType(fields[i]) == JAVATYPE_MESSAGE) {
       if (fields[i]->is_repeated()) {
         int size = reflection->FieldSize(message, fields[i]);
         for (int j = 0; j < size; j++) {
@@ -82,6 +82,7 @@ bool UsesExtensions(const Message& message) {
   return false;
 }
 
+
 }  // namespace
 
 FileGenerator::FileGenerator(const FileDescriptor* file)
@@ -134,7 +135,9 @@ void FileGenerator::Generate(io::Printer* printer) {
   // fully-qualified names in the generated source.
   printer->Print(
     "// Generated by the protocol buffer compiler.  DO NOT EDIT!\n"
-    "\n");
+    "// source: $filename$\n"
+    "\n",
+    "filename", file_->name());
   if (!java_package_.empty()) {
     printer->Print(
       "package $package$;\n"
@@ -178,8 +181,10 @@ void FileGenerator::Generate(io::Printer* printer) {
     for (int i = 0; i < file_->message_type_count(); i++) {
       MessageGenerator(file_->message_type(i)).Generate(printer);
     }
-    for (int i = 0; i < file_->service_count(); i++) {
-      ServiceGenerator(file_->service(i)).Generate(printer);
+    if (HasGenericServices(file_)) {
+      for (int i = 0; i < file_->service_count(); i++) {
+        ServiceGenerator(file_->service(i)).Generate(printer);
+      }
     }
   }
 
@@ -228,6 +233,10 @@ void FileGenerator::Generate(io::Printer* printer) {
     "\n"
     "public static void internalForceInit() {}\n");
 
+  printer->Print(
+    "\n"
+    "// @@protoc_insertion_point(outer_class_scope)\n");
+
   printer->Outdent();
   printer->Print("}\n");
 }
@@ -245,6 +254,7 @@ void FileGenerator::GenerateEmbeddedDescriptor(io::Printer* printer) {
   // embedded raw, which is what we want.
   FileDescriptorProto file_proto;
   file_->CopyTo(&file_proto);
+
   string file_data;
   file_proto.SerializeToString(&file_data);
 
@@ -343,9 +353,11 @@ void FileGenerator::GenerateEmbeddedDescriptor(io::Printer* printer) {
     "    new com.google.protobuf.Descriptors.FileDescriptor[] {\n");
 
   for (int i = 0; i < file_->dependency_count(); i++) {
-    printer->Print(
-      "      $dependency$.getDescriptor(),\n",
-      "dependency", ClassName(file_->dependency(i)));
+    if (ShouldIncludeDependency(file_->dependency(i))) {
+      printer->Print(
+        "      $dependency$.getDescriptor(),\n",
+        "dependency", ClassName(file_->dependency(i)));
+    }
   }
 
   printer->Print(
@@ -396,14 +408,20 @@ void FileGenerator::GenerateSiblings(const string& package_dir,
                                         file_->message_type(i),
                                         output_directory, file_list);
     }
-    for (int i = 0; i < file_->service_count(); i++) {
-      GenerateSibling<ServiceGenerator>(package_dir, java_package_,
-                                        file_->service(i),
-                                        output_directory, file_list);
+    if (HasGenericServices(file_)) {
+      for (int i = 0; i < file_->service_count(); i++) {
+        GenerateSibling<ServiceGenerator>(package_dir, java_package_,
+                                          file_->service(i),
+                                          output_directory, file_list);
+      }
     }
   }
 }
 
+bool FileGenerator::ShouldIncludeDependency(const FileDescriptor* descriptor) {
+  return true;
+}
+
 }  // namespace java
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/java/java_file.h b/src/google/protobuf/compiler/java/java_file.h
index cb82cea2..9e35d330 100644
--- a/src/google/protobuf/compiler/java/java_file.h
+++ b/src/google/protobuf/compiler/java/java_file.h
@@ -77,6 +77,11 @@ class FileGenerator {
   const string& classname()    { return classname_;    }
 
  private:
+  // Returns whether the dependency should be included in the output file.
+  // Always returns true for opensource, but used internally at Google to help
+  // improve compatibility with version 1 of protocol buffers.
+  bool ShouldIncludeDependency(const FileDescriptor* descriptor);
+
   const FileDescriptor* file_;
   string java_package_;
   string classname_;
diff --git a/src/google/protobuf/compiler/java/java_generator.cc b/src/google/protobuf/compiler/java/java_generator.cc
index 8ed3affb..745b55ae 100644
--- a/src/google/protobuf/compiler/java/java_generator.cc
+++ b/src/google/protobuf/compiler/java/java_generator.cc
@@ -45,6 +45,7 @@ namespace protobuf {
 namespace compiler {
 namespace java {
 
+
 JavaGenerator::JavaGenerator() {}
 JavaGenerator::~JavaGenerator() {}
 
diff --git a/src/google/protobuf/compiler/java/java_helpers.cc b/src/google/protobuf/compiler/java/java_helpers.cc
index dc6748e3..7ed0c3cc 100644
--- a/src/google/protobuf/compiler/java/java_helpers.cc
+++ b/src/google/protobuf/compiler/java/java_helpers.cc
@@ -32,6 +32,7 @@
 //  Based on original Protocol Buffers design by
 //  Sanjay Ghemawat, Jeff Dean, and others.
 
+#include <limits>
 #include <vector>
 
 #include <google/protobuf/compiler/java/java_helpers.h>
@@ -57,7 +58,7 @@ const string& FieldName(const FieldDescriptor* field) {
   // Groups are hacky:  The name of the field is just the lower-cased name
   // of the group type.  In Java, though, we would like to retain the original
   // capitalization of the type name.
-  if (field->type() == FieldDescriptor::TYPE_GROUP) {
+  if (GetType(field) == FieldDescriptor::TYPE_GROUP) {
     return field->message_type()->name();
   } else {
     return field->name();
@@ -178,8 +179,12 @@ string FieldConstantName(const FieldDescriptor *field) {
   return name;
 }
 
-JavaType GetJavaType(FieldDescriptor::Type field_type) {
-  switch (field_type) {
+FieldDescriptor::Type GetType(const FieldDescriptor* field) {
+  return field->type();
+}
+
+JavaType GetJavaType(const FieldDescriptor* field) {
+  switch (GetType(field)) {
     case FieldDescriptor::TYPE_INT32:
     case FieldDescriptor::TYPE_UINT32:
     case FieldDescriptor::TYPE_SINT32:
@@ -254,7 +259,7 @@ bool AllAscii(const string& text) {
 }
 
 string DefaultValue(const FieldDescriptor* field) {
-  // Switch on cpp_type since we need to know which default_value_* method
+  // Switch on CppType since we need to know which default_value_* method
   // of FieldDescriptor to call.
   switch (field->cpp_type()) {
     case FieldDescriptor::CPPTYPE_INT32:
@@ -267,14 +272,34 @@ string DefaultValue(const FieldDescriptor* field) {
     case FieldDescriptor::CPPTYPE_UINT64:
       return SimpleItoa(static_cast<int64>(field->default_value_uint64())) +
              "L";
-    case FieldDescriptor::CPPTYPE_DOUBLE:
-      return SimpleDtoa(field->default_value_double()) + "D";
-    case FieldDescriptor::CPPTYPE_FLOAT:
-      return SimpleFtoa(field->default_value_float()) + "F";
+    case FieldDescriptor::CPPTYPE_DOUBLE: {
+      double value = field->default_value_double();
+      if (value == numeric_limits<double>::infinity()) {
+        return "Double.POSITIVE_INFINITY";
+      } else if (value == -numeric_limits<double>::infinity()) {
+        return "Double.NEGATIVE_INFINITY";
+      } else if (value != value) {
+        return "Double.NaN";
+      } else {
+        return SimpleDtoa(value) + "D";
+      }
+    }
+    case FieldDescriptor::CPPTYPE_FLOAT: {
+      float value = field->default_value_float();
+      if (value == numeric_limits<float>::infinity()) {
+        return "Float.POSITIVE_INFINITY";
+      } else if (value == -numeric_limits<float>::infinity()) {
+        return "Float.NEGATIVE_INFINITY";
+      } else if (value != value) {
+        return "Float.NaN";
+      } else {
+        return SimpleFtoa(value) + "F";
+      }
+    }
     case FieldDescriptor::CPPTYPE_BOOL:
       return field->default_value_bool() ? "true" : "false";
     case FieldDescriptor::CPPTYPE_STRING:
-      if (field->type() == FieldDescriptor::TYPE_BYTES) {
+      if (GetType(field) == FieldDescriptor::TYPE_BYTES) {
         if (field->has_default_value()) {
           // See comments in Internal.java for gory details.
           return strings::Substitute(
diff --git a/src/google/protobuf/compiler/java/java_helpers.h b/src/google/protobuf/compiler/java/java_helpers.h
index f1b643c3..3c8974c9 100644
--- a/src/google/protobuf/compiler/java/java_helpers.h
+++ b/src/google/protobuf/compiler/java/java_helpers.h
@@ -93,6 +93,11 @@ string ClassName(const FileDescriptor* descriptor);
 // number constant.
 string FieldConstantName(const FieldDescriptor *field);
 
+// Returns the type of the FieldDescriptor.
+// This does nothing interesting for the open source release, but is used for
+// hacks that improve compatability with version 1 protocol buffers at Google.
+FieldDescriptor::Type GetType(const FieldDescriptor* field);
+
 enum JavaType {
   JAVATYPE_INT,
   JAVATYPE_LONG,
@@ -105,11 +110,7 @@ enum JavaType {
   JAVATYPE_MESSAGE
 };
 
-JavaType GetJavaType(FieldDescriptor::Type field_type);
-
-inline JavaType GetJavaType(const FieldDescriptor* field) {
-  return GetJavaType(field->type());
-}
+JavaType GetJavaType(const FieldDescriptor* field);
 
 // Get the fully-qualified class name for a boxed primitive type, e.g.
 // "java.lang.Integer" for JAVATYPE_INT.  Returns NULL for enum and message
@@ -145,6 +146,13 @@ inline bool HasDescriptorMethods(const FileDescriptor* descriptor) {
            FileOptions::LITE_RUNTIME;
 }
 
+// Should we generate generic services for this file?
+inline bool HasGenericServices(const FileDescriptor *file) {
+  return file->service_count() > 0 &&
+         file->options().optimize_for() != FileOptions::LITE_RUNTIME &&
+         file->options().java_generic_services();
+}
+
 }  // namespace java
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/java/java_message.cc b/src/google/protobuf/compiler/java/java_message.cc
index 99b57c95..1f8e209c 100644
--- a/src/google/protobuf/compiler/java/java_message.cc
+++ b/src/google/protobuf/compiler/java/java_message.cc
@@ -127,7 +127,7 @@ static bool HasRequiredFields(
     if (field->is_required()) {
       return true;
     }
-    if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
+    if (GetJavaType(field) == JAVATYPE_MESSAGE) {
       if (HasRequiredFields(field->message_type(), already_seen)) {
         return true;
       }
@@ -292,9 +292,14 @@ void MessageGenerator::Generate(io::Printer* printer) {
   printer->Indent();
   printer->Print(
     "// Use $classname$.newBuilder() to construct.\n"
-    "private $classname$() {}\n"
+    "private $classname$() {\n"
+    "  initFields();\n"
+    "}\n"
+    // Used when constructing the default instance, which cannot be initialized
+    // immediately because it may cyclically refer to other default instances.
+    "private $classname$(boolean noInit) {}\n"
     "\n"
-    "private static final $classname$ defaultInstance = new $classname$();\n"
+    "private static final $classname$ defaultInstance;\n"
     "public static $classname$ getDefaultInstance() {\n"
     "  return defaultInstance;\n"
     "}\n"
@@ -344,6 +349,17 @@ void MessageGenerator::Generate(io::Printer* printer) {
     printer->Print("\n");
   }
 
+  // Called by the constructor, except in the case of the default instance,
+  // in which case this is called by static init code later on.
+  printer->Print("private void initFields() {\n");
+  printer->Indent();
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    field_generators_.get(descriptor_->field(i))
+                     .GenerateInitializationCode(printer);
+  }
+  printer->Outdent();
+  printer->Print("}\n");
+
   if (HasGeneratedMethods(descriptor_)) {
     GenerateIsInitialized(printer);
     GenerateMessageSerializationMethods(printer);
@@ -352,25 +368,23 @@ void MessageGenerator::Generate(io::Printer* printer) {
   GenerateParseFromMethods(printer);
   GenerateBuilder(printer);
 
-  if (HasDescriptorMethods(descriptor_)) {
-    // Force the static initialization code for the file to run, since it may
-    // initialize static variables declared in this class.
-    printer->Print(
-      "\n"
-      "static {\n"
-      "  $file$.getDescriptor();\n"
-      "}\n",
-      "file", ClassName(descriptor_->file()));
-  }
-
   // Force initialization of outer class.  Otherwise, nested extensions may
-  // not be initialized.
+  // not be initialized.  Also carefully initialize the default instance in
+  // such a way that it doesn't conflict with other initialization.
   printer->Print(
     "\n"
     "static {\n"
+    "  defaultInstance = new $classname$(true);\n"
     "  $file$.internalForceInit();\n"
+    "  defaultInstance.initFields();\n"
     "}\n",
-    "file", ClassName(descriptor_->file()));
+    "file", ClassName(descriptor_->file()),
+    "classname", descriptor_->name());
+
+  printer->Print(
+    "\n"
+    "// @@protoc_insertion_point(class_scope:$full_name$)\n",
+    "full_name", descriptor_->full_name());
 
   printer->Outdent();
   printer->Print("}\n\n");
@@ -529,14 +543,23 @@ GenerateParseFromMethods(io::Printer* printer) {
     "}\n"
     "public static $classname$ parseDelimitedFrom(java.io.InputStream input)\n"
     "    throws java.io.IOException {\n"
-    "  return newBuilder().mergeDelimitedFrom(input).buildParsed();\n"
+    "  Builder builder = newBuilder();\n"
+    "  if (builder.mergeDelimitedFrom(input)) {\n"
+    "    return builder.buildParsed();\n"
+    "  } else {\n"
+    "    return null;\n"
+    "  }\n"
     "}\n"
     "public static $classname$ parseDelimitedFrom(\n"
     "    java.io.InputStream input,\n"
     "    com.google.protobuf.ExtensionRegistryLite extensionRegistry)\n"
     "    throws java.io.IOException {\n"
-    "  return newBuilder().mergeDelimitedFrom(input, extensionRegistry)\n"
-    "           .buildParsed();\n"
+    "  Builder builder = newBuilder();\n"
+    "  if (builder.mergeDelimitedFrom(input, extensionRegistry)) {\n"
+    "    return builder.buildParsed();\n"
+    "  } else {\n"
+    "    return null;\n"
+    "  }\n"
     "}\n"
     "public static $classname$ parseFrom(\n"
     "    com.google.protobuf.CodedInputStream input)\n"
@@ -827,7 +850,7 @@ void MessageGenerator::GenerateBuilderParsingMethods(io::Printer* printer) {
   for (int i = 0; i < descriptor_->field_count(); i++) {
     const FieldDescriptor* field = sorted_fields[i];
     uint32 tag = WireFormatLite::MakeTag(field->number(),
-      WireFormat::WireTypeForField(field));
+      WireFormat::WireTypeForFieldType(field->type()));
 
     printer->Print(
       "case $tag$: {\n",
@@ -840,6 +863,24 @@ void MessageGenerator::GenerateBuilderParsingMethods(io::Printer* printer) {
     printer->Print(
       "  break;\n"
       "}\n");
+
+    if (field->is_packable()) {
+      // To make packed = true wire compatible, we generate parsing code from a
+      // packed version of this field regardless of field->options().packed().
+      uint32 packed_tag = WireFormatLite::MakeTag(field->number(),
+        WireFormatLite::WIRETYPE_LENGTH_DELIMITED);
+      printer->Print(
+        "case $tag$: {\n",
+        "tag", SimpleItoa(packed_tag));
+      printer->Indent();
+
+      field_generators_.get(field).GenerateParsingCodeFromPacked(printer);
+
+      printer->Outdent();
+      printer->Print(
+        "  break;\n"
+        "}\n");
+    }
   }
 
   printer->Outdent();
@@ -875,7 +916,7 @@ void MessageGenerator::GenerateIsInitialized(io::Printer* printer) {
   // Now check that all embedded messages are initialized.
   for (int i = 0; i < descriptor_->field_count(); i++) {
     const FieldDescriptor* field = descriptor_->field(i);
-    if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE &&
+    if (GetJavaType(field) == JAVATYPE_MESSAGE &&
         HasRequiredFields(field->message_type())) {
       switch (field->label()) {
         case FieldDescriptor::LABEL_REQUIRED:
diff --git a/src/google/protobuf/compiler/java/java_message_field.cc b/src/google/protobuf/compiler/java/java_message_field.cc
index bbddddde..71edc024 100644
--- a/src/google/protobuf/compiler/java/java_message_field.cc
+++ b/src/google/protobuf/compiler/java/java_message_field.cc
@@ -59,7 +59,7 @@ void SetMessageVariables(const FieldDescriptor* descriptor,
   (*variables)["number"] = SimpleItoa(descriptor->number());
   (*variables)["type"] = ClassName(descriptor->message_type());
   (*variables)["group_or_message"] =
-    (descriptor->type() == FieldDescriptor::TYPE_GROUP) ?
+    (GetType(descriptor) == FieldDescriptor::TYPE_GROUP) ?
     "Group" : "Message";
 }
 
@@ -79,7 +79,7 @@ void MessageFieldGenerator::
 GenerateMembers(io::Printer* printer) const {
   printer->Print(variables_,
     "private boolean has$capitalized_name$;\n"
-    "private $type$ $name$_ = $type$.getDefaultInstance();\n"
+    "private $type$ $name$_;\n"
     "public boolean has$capitalized_name$() { return has$capitalized_name$; }\n"
     "public $type$ get$capitalized_name$() { return $name$_; }\n");
 }
@@ -125,6 +125,11 @@ GenerateBuilderMembers(io::Printer* printer) const {
 }
 
 void MessageFieldGenerator::
+GenerateInitializationCode(io::Printer* printer) const {
+  printer->Print(variables_, "$name$_ = $type$.getDefaultInstance();\n");
+}
+
+void MessageFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if (other.has$capitalized_name$()) {\n"
@@ -145,7 +150,7 @@ GenerateParsingCode(io::Printer* printer) const {
     "  subBuilder.mergeFrom(get$capitalized_name$());\n"
     "}\n");
 
-  if (descriptor_->type() == FieldDescriptor::TYPE_GROUP) {
+  if (GetType(descriptor_) == FieldDescriptor::TYPE_GROUP) {
     printer->Print(variables_,
       "input.readGroup($number$, subBuilder, extensionRegistry);\n");
   } else {
@@ -262,6 +267,11 @@ GenerateBuilderMembers(io::Printer* printer) const {
 }
 
 void RepeatedMessageFieldGenerator::
+GenerateInitializationCode(io::Printer* printer) const {
+  // Initialized inline.
+}
+
+void RepeatedMessageFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if (!other.$name$_.isEmpty()) {\n"
@@ -286,7 +296,7 @@ GenerateParsingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "$type$.Builder subBuilder = $type$.newBuilder();\n");
 
-  if (descriptor_->type() == FieldDescriptor::TYPE_GROUP) {
+  if (GetType(descriptor_) == FieldDescriptor::TYPE_GROUP) {
     printer->Print(variables_,
       "input.readGroup($number$, subBuilder, extensionRegistry);\n");
   } else {
diff --git a/src/google/protobuf/compiler/java/java_message_field.h b/src/google/protobuf/compiler/java/java_message_field.h
index 90a90976..66bdd884 100644
--- a/src/google/protobuf/compiler/java/java_message_field.h
+++ b/src/google/protobuf/compiler/java/java_message_field.h
@@ -52,6 +52,7 @@ class MessageFieldGenerator : public FieldGenerator {
   // implements FieldGenerator ---------------------------------------
   void GenerateMembers(io::Printer* printer) const;
   void GenerateBuilderMembers(io::Printer* printer) const;
+  void GenerateInitializationCode(io::Printer* printer) const;
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateBuildingCode(io::Printer* printer) const;
   void GenerateParsingCode(io::Printer* printer) const;
@@ -75,6 +76,7 @@ class RepeatedMessageFieldGenerator : public FieldGenerator {
   // implements FieldGenerator ---------------------------------------
   void GenerateMembers(io::Printer* printer) const;
   void GenerateBuilderMembers(io::Printer* printer) const;
+  void GenerateInitializationCode(io::Printer* printer) const;
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateBuildingCode(io::Printer* printer) const;
   void GenerateParsingCode(io::Printer* printer) const;
diff --git a/src/google/protobuf/compiler/java/java_primitive_field.cc b/src/google/protobuf/compiler/java/java_primitive_field.cc
index 1fbca5a2..f6179bfa 100644
--- a/src/google/protobuf/compiler/java/java_primitive_field.cc
+++ b/src/google/protobuf/compiler/java/java_primitive_field.cc
@@ -93,7 +93,7 @@ bool IsReferenceType(JavaType type) {
 }
 
 const char* GetCapitalizedType(const FieldDescriptor* field) {
-  switch (field->type()) {
+  switch (GetType(field)) {
     case FieldDescriptor::TYPE_INT32   : return "Int32"   ;
     case FieldDescriptor::TYPE_UINT32  : return "UInt32"  ;
     case FieldDescriptor::TYPE_SINT32  : return "SInt32"  ;
@@ -166,7 +166,7 @@ void SetPrimitiveVariables(const FieldDescriptor* descriptor,
   (*variables)["capitalized_type"] = GetCapitalizedType(descriptor);
   (*variables)["tag"] = SimpleItoa(WireFormat::MakeTag(descriptor));
   (*variables)["tag_size"] = SimpleItoa(
-      WireFormat::TagSize(descriptor->number(), descriptor->type()));
+      WireFormat::TagSize(descriptor->number(), GetType(descriptor)));
   if (IsReferenceType(GetJavaType(descriptor))) {
     (*variables)["null_check"] =
         "  if (value == null) {\n"
@@ -175,7 +175,7 @@ void SetPrimitiveVariables(const FieldDescriptor* descriptor,
   } else {
     (*variables)["null_check"] = "";
   }
-  int fixed_size = FixedSize(descriptor->type());
+  int fixed_size = FixedSize(GetType(descriptor));
   if (fixed_size != -1) {
     (*variables)["fixed_size"] = SimpleItoa(fixed_size);
   }
@@ -218,7 +218,8 @@ GenerateBuilderMembers(io::Printer* printer) const {
     "}\n"
     "public Builder clear$capitalized_name$() {\n"
     "  result.has$capitalized_name$ = false;\n");
-  if (descriptor_->cpp_type() == FieldDescriptor::CPPTYPE_STRING) {
+  JavaType type = GetJavaType(descriptor_);
+  if (type == JAVATYPE_STRING || type == JAVATYPE_BYTES) {
     // 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_,
@@ -233,6 +234,11 @@ GenerateBuilderMembers(io::Printer* printer) const {
 }
 
 void PrimitiveFieldGenerator::
+GenerateInitializationCode(io::Printer* printer) const {
+  // Initialized inline.
+}
+
+void PrimitiveFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if (other.has$capitalized_name$()) {\n"
@@ -346,6 +352,11 @@ GenerateBuilderMembers(io::Printer* printer) const {
 }
 
 void RepeatedPrimitiveFieldGenerator::
+GenerateInitializationCode(io::Printer* printer) const {
+  // Initialized inline.
+}
+
+void RepeatedPrimitiveFieldGenerator::
 GenerateMergingCode(io::Printer* printer) const {
   printer->Print(variables_,
     "if (!other.$name$_.isEmpty()) {\n"
@@ -367,18 +378,19 @@ GenerateBuildingCode(io::Printer* printer) const {
 
 void RepeatedPrimitiveFieldGenerator::
 GenerateParsingCode(io::Printer* printer) const {
-  if (descriptor_->options().packed()) {
-    printer->Print(variables_,
-      "int length = input.readRawVarint32();\n"
-      "int limit = input.pushLimit(length);\n"
-      "while (input.getBytesUntilLimit() > 0) {\n"
-      "  add$capitalized_name$(input.read$capitalized_type$());\n"
-      "}\n"
-      "input.popLimit(limit);\n");
-  } else {
-    printer->Print(variables_,
-      "add$capitalized_name$(input.read$capitalized_type$());\n");
-  }
+  printer->Print(variables_,
+    "add$capitalized_name$(input.read$capitalized_type$());\n");
+}
+
+void RepeatedPrimitiveFieldGenerator::
+GenerateParsingCodeFromPacked(io::Printer* printer) const {
+  printer->Print(variables_,
+    "int length = input.readRawVarint32();\n"
+    "int limit = input.pushLimit(length);\n"
+    "while (input.getBytesUntilLimit() > 0) {\n"
+    "  add$capitalized_name$(input.read$capitalized_type$());\n"
+    "}\n"
+    "input.popLimit(limit);\n");
 }
 
 void RepeatedPrimitiveFieldGenerator::
@@ -407,7 +419,7 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
     "  int dataSize = 0;\n");
   printer->Indent();
 
-  if (FixedSize(descriptor_->type()) == -1) {
+  if (FixedSize(GetType(descriptor_)) == -1) {
     printer->Print(variables_,
       "for ($type$ element : get$capitalized_name$List()) {\n"
       "  dataSize += com.google.protobuf.CodedOutputStream\n"
diff --git a/src/google/protobuf/compiler/java/java_primitive_field.h b/src/google/protobuf/compiler/java/java_primitive_field.h
index f9da0a62..4e482a05 100644
--- a/src/google/protobuf/compiler/java/java_primitive_field.h
+++ b/src/google/protobuf/compiler/java/java_primitive_field.h
@@ -52,6 +52,7 @@ class PrimitiveFieldGenerator : public FieldGenerator {
   // implements FieldGenerator ---------------------------------------
   void GenerateMembers(io::Printer* printer) const;
   void GenerateBuilderMembers(io::Printer* printer) const;
+  void GenerateInitializationCode(io::Printer* printer) const;
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateBuildingCode(io::Printer* printer) const;
   void GenerateParsingCode(io::Printer* printer) const;
@@ -75,9 +76,11 @@ class RepeatedPrimitiveFieldGenerator : public FieldGenerator {
   // implements FieldGenerator ---------------------------------------
   void GenerateMembers(io::Printer* printer) const;
   void GenerateBuilderMembers(io::Printer* printer) const;
+  void GenerateInitializationCode(io::Printer* printer) const;
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateBuildingCode(io::Printer* printer) const;
   void GenerateParsingCode(io::Printer* printer) const;
+  void GenerateParsingCodeFromPacked(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;