1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2008 Google Inc. All rights reserved.
3 // https://developers.google.com/protocol-buffers/
4 //
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are
7 // met:
8 //
9 // * Redistributions of source code must retain the above copyright
10 // notice, this list of conditions and the following disclaimer.
11 // * Redistributions in binary form must reproduce the above
12 // copyright notice, this list of conditions and the following disclaimer
13 // in the documentation and/or other materials provided with the
14 // distribution.
15 // * Neither the name of Google Inc. nor the names of its
16 // contributors may be used to endorse or promote products derived from
17 // this software without specific prior written permission.
18 //
19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31 // Author: xiaofeng@google.com (Feng Xiao)
32
33 #include <google/protobuf/compiler/java/java_shared_code_generator.h>
34
35 #include <memory>
36
37 #include <google/protobuf/compiler/java/java_helpers.h>
38 #include <google/protobuf/compiler/java/java_name_resolver.h>
39 #include <google/protobuf/compiler/code_generator.h>
40 #include <google/protobuf/io/printer.h>
41 #include <google/protobuf/io/zero_copy_stream.h>
42 #include <google/protobuf/descriptor.pb.h>
43 #include <google/protobuf/descriptor.h>
44 #include <google/protobuf/stubs/strutil.h>
45
46 namespace google {
47 namespace protobuf {
48 namespace compiler {
49 namespace java {
50
SharedCodeGenerator(const FileDescriptor * file)51 SharedCodeGenerator::SharedCodeGenerator(const FileDescriptor* file)
52 : name_resolver_(new ClassNameResolver), file_(file) {
53 }
54
~SharedCodeGenerator()55 SharedCodeGenerator::~SharedCodeGenerator() {
56 }
57
Generate(GeneratorContext * context,vector<string> * file_list)58 void SharedCodeGenerator::Generate(GeneratorContext* context,
59 vector<string>* file_list) {
60 string java_package = FileJavaPackage(file_);
61 string package_dir = JavaPackageToDir(java_package);
62
63 if (HasDescriptorMethods(file_)) {
64 // Generate descriptors.
65 string classname = name_resolver_->GetDescriptorClassName(file_);
66 string filename = package_dir + classname + ".java";
67 file_list->push_back(filename);
68 scoped_ptr<io::ZeroCopyOutputStream> output(context->Open(filename));
69 scoped_ptr<io::Printer> printer(new io::Printer(output.get(), '$'));
70
71 printer->Print(
72 "// Generated by the protocol buffer compiler. DO NOT EDIT!\n"
73 "// source: $filename$\n"
74 "\n",
75 "filename", file_->name());
76 if (!java_package.empty()) {
77 printer->Print(
78 "package $package$;\n"
79 "\n",
80 "package", java_package);
81 }
82 printer->Print(
83 "public final class $classname$ {\n"
84 " public static com.google.protobuf.Descriptors.FileDescriptor\n"
85 " descriptor;\n"
86 " static {\n",
87 "classname", classname);
88 printer->Indent();
89 printer->Indent();
90 GenerateDescriptors(printer.get());
91 printer->Outdent();
92 printer->Outdent();
93 printer->Print(
94 " }\n"
95 "}\n");
96
97 printer.reset();
98 output.reset();
99 }
100 }
101
102
GenerateDescriptors(io::Printer * printer)103 void SharedCodeGenerator::GenerateDescriptors(io::Printer* printer) {
104 // Embed the descriptor. We simply serialize the entire FileDescriptorProto
105 // and embed it as a string literal, which is parsed and built into real
106 // descriptors at initialization time. We unfortunately have to put it in
107 // a string literal, not a byte array, because apparently using a literal
108 // byte array causes the Java compiler to generate *instructions* to
109 // initialize each and every byte of the array, e.g. as if you typed:
110 // b[0] = 123; b[1] = 456; b[2] = 789;
111 // This makes huge bytecode files and can easily hit the compiler's internal
112 // code size limits (error "code to large"). String literals are apparently
113 // embedded raw, which is what we want.
114 FileDescriptorProto file_proto;
115 file_->CopyTo(&file_proto);
116
117
118 string file_data;
119 file_proto.SerializeToString(&file_data);
120
121 printer->Print(
122 "java.lang.String[] descriptorData = {\n");
123 printer->Indent();
124
125 // Only write 40 bytes per line.
126 static const int kBytesPerLine = 40;
127 for (int i = 0; i < file_data.size(); i += kBytesPerLine) {
128 if (i > 0) {
129 // Every 400 lines, start a new string literal, in order to avoid the
130 // 64k length limit.
131 if (i % 400 == 0) {
132 printer->Print(",\n");
133 } else {
134 printer->Print(" +\n");
135 }
136 }
137 printer->Print("\"$data$\"",
138 "data", CEscape(file_data.substr(i, kBytesPerLine)));
139 }
140
141 printer->Outdent();
142 printer->Print("\n};\n");
143
144 // -----------------------------------------------------------------
145 // Create the InternalDescriptorAssigner.
146
147 printer->Print(
148 "com.google.protobuf.Descriptors.FileDescriptor."
149 "InternalDescriptorAssigner assigner =\n"
150 " new com.google.protobuf.Descriptors.FileDescriptor."
151 " InternalDescriptorAssigner() {\n"
152 " public com.google.protobuf.ExtensionRegistry assignDescriptors(\n"
153 " com.google.protobuf.Descriptors.FileDescriptor root) {\n"
154 " descriptor = root;\n"
155 // Custom options will be handled when immutable messages' outer class is
156 // loaded. Here we just return null and let custom options be unknown
157 // fields.
158 " return null;\n"
159 " }\n"
160 " };\n");
161
162 // -----------------------------------------------------------------
163 // Find out all dependencies.
164 vector<pair<string, string> > dependencies;
165 for (int i = 0; i < file_->dependency_count(); i++) {
166 if (ShouldIncludeDependency(file_->dependency(i))) {
167 string filename = file_->dependency(i)->name();
168 string classname = FileJavaPackage(file_->dependency(i)) + "." +
169 name_resolver_->GetDescriptorClassName(
170 file_->dependency(i));
171 dependencies.push_back(make_pair(filename, classname));
172 }
173 }
174
175 // -----------------------------------------------------------------
176 // Invoke internalBuildGeneratedFileFrom() to build the file.
177 printer->Print(
178 "com.google.protobuf.Descriptors.FileDescriptor\n"
179 " .internalBuildGeneratedFileFrom(descriptorData,\n"
180 " new com.google.protobuf.Descriptors.FileDescriptor[] {\n");
181
182 for (int i = 0; i < dependencies.size(); i++) {
183 const string& dependency = dependencies[i].second;
184 printer->Print(
185 " $dependency$.getDescriptor(),\n",
186 "dependency", dependency);
187 }
188
189 printer->Print(
190 " }, assigner);\n");
191 }
192
ShouldIncludeDependency(const FileDescriptor * descriptor)193 bool SharedCodeGenerator::ShouldIncludeDependency(
194 const FileDescriptor* descriptor) {
195 return true;
196 }
197
198 } // namespace java
199 } // namespace compiler
200 } // namespace protobuf
201 } // namespace google
202