// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// http://code.google.com/p/protobuf/
//
// 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
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Author: kenton@google.com (Kenton Varda)
// Based on original Protocol Buffers design by
// Sanjay Ghemawat, Jeff Dean, and others.
#include <google/protobuf/compiler/java/java_file.h>
#include <google/protobuf/compiler/java/java_enum.h>
#include <google/protobuf/compiler/java/java_service.h>
#include <google/protobuf/compiler/java/java_extension.h>
#include <google/protobuf/compiler/java/java_helpers.h>
#include <google/protobuf/compiler/java/java_message.h>
#include <google/protobuf/compiler/code_generator.h>
#include <google/protobuf/io/printer.h>
#include <google/protobuf/io/zero_copy_stream.h>
#include <google/protobuf/descriptor.pb.h>
#include <google/protobuf/dynamic_message.h>
#include <google/protobuf/stubs/strutil.h>
namespace google {
namespace protobuf {
namespace compiler {
namespace java {
namespace {
// Recursively searches the given message to collect extensions.
// Returns true if all the extensions can be recognized. The extensions will be
// appended in to the extensions parameter.
// Returns false when there are unknown fields, in which case the data in the
// extensions output parameter is not reliable and should be discarded.
bool CollectExtensions(const Message& message,
vector<const FieldDescriptor*>* extensions) {
const Reflection* reflection = message.GetReflection();
// There are unknown fields that could be extensions, thus this call fails.
if (reflection->GetUnknownFields(message).field_count() > 0) return false;
vector<const FieldDescriptor*> fields;
reflection->ListFields(message, &fields);
for (int i = 0; i < fields.size(); i++) {
if (fields[i]->is_extension()) extensions->push_back(fields[i]);
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++) {
const Message& sub_message =
reflection->GetRepeatedMessage(message, fields[i], j);
if (!CollectExtensions(sub_message, extensions)) return false;
}
} else {
const Message& sub_message = reflection->GetMessage(message, fields[i]);
if (!CollectExtensions(sub_message, extensions)) return false;
}
}
}
return true;
}
// Finds all extensions in the given message and its sub-messages. If the
// message contains unknown fields (which could be extensions), then those
// extensions are defined in alternate_pool.
// The message will be converted to a DynamicMessage backed by alternate_pool
// in order to handle this case.
void CollectExtensions(const FileDescriptorProto& file_proto,
const DescriptorPool& alternate_pool,
vector<const FieldDescriptor*>* extensions,
const string& file_data) {
if (!CollectExtensions(file_proto, extensions)) {
// There are unknown fields in the file_proto, which are probably
// extensions. We need to parse the data into a dynamic message based on the
// builder-pool to find out all extensions.
const Descriptor* file_proto_desc = alternate_pool.FindMessageTypeByName(
file_proto.GetDescriptor()->full_name());
GOOGLE_CHECK(file_proto_desc)
<< "Find unknown fields in FileDescriptorProto when building "
<< file_proto.name()
<< ". It's likely that those fields are custom options, however, "
"descriptor.proto is not in the transitive dependencies. "
"This normally should not happen. Please report a bug.";
DynamicMessageFactory factory;
scoped_ptr<Message> dynamic_file_proto(
factory.GetPrototype(file_proto_desc)->New());
GOOGLE_CHECK(dynamic_file_proto.get() != NULL);
GOOGLE_CHECK(dynamic_file_proto->ParseFromString(file_data));
// Collect the extensions again from the dynamic message. There should be no
// more unknown fields this time, i.e. all the custom options should be
// parsed as extensions now.
extensions->clear();
GOOGLE_CHECK(CollectExtensions(*dynamic_file_proto, extensions))
<< "Find unknown fields in FileDescriptorProto when building "
<< file_proto.name()
<< ". It's likely that those fields are custom options, however, "
"those options cannot be recognized in the builder pool. "
"This normally should not happen. Please report a bug.";
}
}
} // namespace
FileGenerator::FileGenerator(const FileDescriptor* file)
: file_(file),
java_package_(FileJavaPackage(file)),
classname_(FileClassName(file)) {
}
FileGenerator::~FileGenerator() {}
bool FileGenerator::Validate(string* error) {
// Check that no class name matches the file's class name. This is a common
// problem that leads to Java compile errors that can be hard to understand.
// It's especially bad when using the java_multiple_files, since we would
// end up overwriting the outer class with one of the inner ones.
bool found_conflict = false;
for (int i = 0; i < file_->enum_type_count() && !found_conflict; i++) {
if (file_->enum_type(i)->name() == classname_) {
found_conflict = true;
}
}
for (int i = 0; i < file_->message_type_count() && !found_conflict; i++) {
if (file_->message_type(i)->name() == classname_) {
found_conflict = true;
}
}
for (int i = 0; i < file_->service_count() && !found_conflict; i++) {
if (file_->service(i)->name() == classname_) {
found_conflict = true;
}
}
if (found_conflict) {
error->assign(file_->name());
error->append(
": Cannot generate Java output because the file's outer class name, \"");
error->append(classname_);
error->append(
"\", matches the name of one of the types declared inside it. "
"Please either rename the type or use the java_outer_classname "
"option to specify a different outer class name for the .proto file.");
return false;
}
return true;
}
void FileGenerator::Generate(io::Printer* printer) {
// We don't import anything because we refer to all classes by their
// fully-qualified names in the generated source.
printer->Print(
"// Generated by the protocol buffer compiler. DO NOT EDIT!\n"
"// source: $filename$\n"
"\n",
"filename", file_->name());
if (!java_package_.empty()) {
printer->Print(
"package $package$;\n"
"\n",
"package", java_package_);
}
printer->Print(
"public final class $classname$ {\n"
" private $classname$() {}\n",
"classname", classname_);
printer->Indent();
// -----------------------------------------------------------------
printer->Print(
"public static void registerAllExtensions(\n"
" com.google.protobuf.ExtensionRegistry$lite$ registry) {\n",
"lite", HasDescriptorMethods(file_) ? "" : "Lite");
printer->Indent();
for (int i = 0; i < file_->extension_count(); i++) {
ExtensionGenerator(file_->extension(i)).GenerateRegistrationCode(printer);
}
for (int i = 0; i < file_->message_type_count(); i++) {
MessageGenerator(file_->message_type(i))
.GenerateExtensionRegistrationCode(printer);
}
printer->Outdent();
printer->Print(
"}\n");
// -----------------------------------------------------------------
if (!file_->options().java_multiple_files()) {
for (int i = 0; i < file_->enum_type_count(); i++) {
EnumGenerator(file_->enum_type(i)).Generate(printer);
}
for (int i = 0; i < file_->message_type_count(); i++) {
MessageGenerator messageGenerator(file_->message_type(i));
messageGenerator.GenerateInterface(printer);
messageGenerator.Generate(printer);
}
if (HasGenericServices(file_)) {
for (int i = 0; i < file_->service_count(); i++) {
ServiceGenerator(file_->service(i)).Generate(printer);
}
}
}
// Extensions must be generated in the outer class since they are values,
// not classes.
for (int i = 0; i < file_->extension_count(); i++) {
ExtensionGenerator(file_->extension(i)).Generate(printer);
}
// Static variables.
for (int i = 0; i < file_->message_type_count(); i++) {
// TODO(kenton): Reuse MessageGenerator objects?
MessageGenerator(file_->message_type(i)).GenerateStaticVariables(printer);
}
printer->Print("\n");
if (HasDescriptorMethods(file_)) {
GenerateEmbeddedDescriptor(printer);
} else {
printer->Print(
"static {\n");
printer->Indent();
for (int i = 0; i < file_->message_type_count(); i++) {
// TODO(kenton): Reuse MessageGenerator objects?
MessageGenerator(file_->message_type(i))
.GenerateStaticVariableInitializers(printer);
}
printer->Outdent();
printer->Print(
"}\n");
}
printer->Print(
"\n"
"// @@protoc_insertion_point(outer_class_scope)\n");
printer->Outdent();
printer->Print("}\n");
}
void FileGenerator::GenerateEmbeddedDescriptor(io::Printer* printer) {
// Embed the descriptor. We simply serialize the entire FileDescriptorProto
// and embed it as a string literal, which is parsed and built into real
// descriptors at initialization time. We unfortunately have to put it in
// a string literal, not a byte array, because apparently using a literal
// byte array causes the Java compiler to generate *instructions* to
// initialize each and every byte of the array, e.g. as if you typed:
// b[0] = 123; b[1] = 456; b[2] = 789;
// This makes huge bytecode files and can easily hit the compiler's internal
// code size limits (error "code to large"). String literals are apparently
// embedded raw, which is what we want.
FileDescriptorProto file_proto;
file_->CopyTo(&file_proto);
string file_data;
file_proto.SerializeToString(&file_data);
printer->Print(
"public static com.google.protobuf.Descriptors.FileDescriptor\n"
" getDescriptor() {\n"
" return descriptor;\n"
"}\n"
"private static com.google.protobuf.Descriptors.FileDescriptor\n"
" descriptor;\n"
"static {\n"
" java.lang.String[] descriptorData = {\n");
printer->Indent();
printer->Indent();
// Only write 40 bytes per line.
static const int kBytesPerLine = 40;
for (int i = 0; i < file_data.size(); i += kBytesPerLine) {
if (i > 0) {
// Every 400 lines, start a new string literal, in order to avoid the
// 64k length limit.
if (i % 400 == 0) {
printer->Print(",\n");
} else {
printer->Print(" +\n");
}
}
printer->Print("\"$data$\"",
"data", CEscape(file_data.substr(i, kBytesPerLine)));
}
printer->Outdent();
printer->Print("\n};\n");
// -----------------------------------------------------------------
// Create the InternalDescriptorAssigner.
printer->Print(
"com.google.protobuf.Descriptors.FileDescriptor."
"InternalDescriptorAssigner assigner =\n"
" new com.google.protobuf.Descriptors.FileDescriptor."
"InternalDescriptorAssigner() {\n"
" public com.google.protobuf.ExtensionRegistry assignDescriptors(\n"
" com.google.protobuf.Descriptors.FileDescriptor root) {\n"
" descriptor = root;\n");
printer->Indent();
printer->Indent();
printer->Indent();
for (int i = 0; i < file_->message_type_count(); i++) {
// TODO(kenton): Reuse MessageGenerator objects?
MessageGenerator(file_->message_type(i))
.GenerateStaticVariableInitializers(printer);
}
for (int i = 0; i < file_->extension_count(); i++) {
// TODO(kenton): Reuse ExtensionGenerator objects?
ExtensionGenerator(file_->extension(i))
.GenerateNonNestedInitializationCode(printer);
}
// Proto compiler builds a DescriptorPool, which holds all the descriptors to
// generate, when processing the ".proto" files. We call this DescriptorPool
// the parsed pool (a.k.a. file_->pool()).
//
// Note that when users try to extend the (.*)DescriptorProto in their
// ".proto" files, it does not affect the pre-built FileDescriptorProto class
// in proto compiler. When we put the descriptor data in the file_proto, those
// extensions become unknown fields.
//
// Now we need to find out all the extension value to the (.*)DescriptorProto
// in the file_proto message, and prepare an ExtensionRegistry to return.
//
// To find those extensions, we need to parse the data into a dynamic message
// of the FileDescriptor based on the builder-pool, then we can use
// reflections to find all extension fields
vector<const FieldDescriptor*> extensions;
CollectExtensions(file_proto, *file_->pool(), &extensions, file_data);
if (extensions.size() > 0) {
// Must construct an ExtensionRegistry containing all existing extensions
// and return it.
printer->Print(
"com.google.protobuf.ExtensionRegistry registry =\n"
" com.google.protobuf.ExtensionRegistry.newInstance();\n");
for (int i = 0; i < extensions.size(); i++) {
ExtensionGenerator(extensions[i]).GenerateRegistrationCode(printer);
}
printer->Print(
"return registry;\n");
} else {
printer->Print(
"return null;\n");
}
printer->Outdent();
printer->Outdent();
printer->Outdent();
printer->Print(
" }\n"
" };\n");
// -----------------------------------------------------------------
// Invoke internalBuildGeneratedFileFrom() to build the file.
printer->Print(
"com.google.protobuf.Descriptors.FileDescriptor\n"
" .internalBuildGeneratedFileFrom(descriptorData,\n"
" new com.google.protobuf.Descriptors.FileDescriptor[] {\n");
for (int i = 0; i < file_->dependency_count(); i++) {
if (ShouldIncludeDependency(file_->dependency(i))) {
printer->Print(
" $dependency$.getDescriptor(),\n",
"dependency", ClassName(file_->dependency(i)));
}
}
printer->Print(
" }, assigner);\n");
printer->Outdent();
printer->Print(
"}\n");
}
template<typename GeneratorClass, typename DescriptorClass>
static void GenerateSibling(const string& package_dir,
const string& java_package,
const DescriptorClass* descriptor,
GeneratorContext* context,
vector<string>* file_list,
const string& name_suffix,
void (GeneratorClass::*pfn)(io::Printer* printer)) {
string filename = package_dir + descriptor->name() + name_suffix + ".java";
file_list->push_back(filename);
scoped_ptr<io::ZeroCopyOutputStream> output(context->Open(filename));
io::Printer printer(output.get(), '$');
printer.Print(
"// Generated by the protocol buffer compiler. DO NOT EDIT!\n"
"// source: $filename$\n"
"\n",
"filename", descriptor->file()->name());
if (!java_package.empty()) {
printer.Print(
"package $package$;\n"
"\n",
"package", java_package);
}
GeneratorClass generator(descriptor);
(generator.*pfn)(&printer);
}
void FileGenerator::GenerateSiblings(const string& package_dir,
GeneratorContext* context,
vector<string>* file_list) {
if (file_->options().java_multiple_files()) {
for (int i = 0; i < file_->enum_type_count(); i++) {
GenerateSibling<EnumGenerator>(package_dir, java_package_,
file_->enum_type(i),
context, file_list, "",
&EnumGenerator::Generate);
}
for (int i = 0; i < file_->message_type_count(); i++) {
GenerateSibling<MessageGenerator>(package_dir, java_package_,
file_->message_type(i),
context, file_list, "OrBuilder",
&MessageGenerator::GenerateInterface);
GenerateSibling<MessageGenerator>(package_dir, java_package_,
file_->message_type(i),
context, file_list, "",
&MessageGenerator::Generate);
}
if (HasGenericServices(file_)) {
for (int i = 0; i < file_->service_count(); i++) {
GenerateSibling<ServiceGenerator>(package_dir, java_package_,
file_->service(i),
context, file_list, "",
&ServiceGenerator::Generate);
}
}
}
}
bool FileGenerator::ShouldIncludeDependency(const FileDescriptor* descriptor) {
return true;
}
} // namespace java
} // namespace compiler
} // namespace protobuf
} // namespace google