// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.
// http://code.google.com/p/protobuf/
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// 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/stubs/strutil.h>
namespace google {
namespace protobuf {
namespace compiler {
namespace java {
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"
"\n");
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();
// -----------------------------------------------------------------
// 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 final com.google.protobuf.Descriptors.FileDescriptor\n"
" descriptor = buildDescriptor();\n"
"private static\n"
" com.google.protobuf.Descriptors.FileDescriptor\n"
" buildDescriptor() {\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) printer->Print(" +\n");
printer->Print("\"$data$\"",
"data", CEscape(file_data.substr(i, kBytesPerLine)));
}
printer->Print(";\n");
printer->Outdent();
printer->Print(
"try {\n"
" return 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++) {
printer->Print(
" $dependency$.getDescriptor(),\n",
"dependency", ClassName(file_->dependency(i)));
}
printer->Print(
" });\n"
"} catch (Exception e) {\n"
" throw new RuntimeException(\n"
" \"Failed to parse protocol buffer descriptor for \" +\n"
" \"\\\"$filename$\\\".\", e);\n"
"}\n",
"filename", file_->name());
printer->Outdent();
printer->Print(
"}\n"
"\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(file_->message_type(i)).Generate(printer);
}
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->Outdent();
printer->Print("}\n");
}
template<typename GeneratorClass, typename DescriptorClass>
static void GenerateSibling(const string& package_dir,
const string& java_package,
const DescriptorClass* descriptor,
OutputDirectory* output_directory,
vector<string>* file_list) {
string filename = package_dir + descriptor->name() + ".java";
file_list->push_back(filename);
scoped_ptr<io::ZeroCopyOutputStream> output(
output_directory->Open(filename));
io::Printer printer(output.get(), '$');
printer.Print(
"// Generated by the protocol buffer compiler. DO NOT EDIT!\n"
"\n");
if (!java_package.empty()) {
printer.Print(
"package $package$;\n"
"\n",
"package", java_package);
}
GeneratorClass(descriptor).Generate(&printer);
}
void FileGenerator::GenerateSiblings(const string& package_dir,
OutputDirectory* output_directory,
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),
output_directory, file_list);
}
for (int i = 0; i < file_->message_type_count(); i++) {
GenerateSibling<MessageGenerator>(package_dir, java_package_,
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);
}
}
}
} // namespace java
} // namespace compiler
} // namespace protobuf
} // namespace google
