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: kenton@google.com (Kenton Varda)
32//  Based on original Protocol Buffers design by
33//  Sanjay Ghemawat, Jeff Dean, and others.
34
35#include <map>
36#include <string>
37
38#include <google/protobuf/compiler/java/java_context.h>
39#include <google/protobuf/compiler/java/java_enum.h>
40#include <google/protobuf/compiler/java/java_doc_comment.h>
41#include <google/protobuf/compiler/java/java_helpers.h>
42#include <google/protobuf/compiler/java/java_name_resolver.h>
43#include <google/protobuf/io/printer.h>
44#include <google/protobuf/descriptor.pb.h>
45#include <google/protobuf/stubs/strutil.h>
46
47namespace google {
48namespace protobuf {
49namespace compiler {
50namespace java {
51
52namespace {
53bool EnumHasCustomOptions(const EnumDescriptor* descriptor) {
54  if (descriptor->options().unknown_fields().field_count() > 0) return true;
55  for (int i = 0; i < descriptor->value_count(); ++i) {
56    const EnumValueDescriptor* value = descriptor->value(i);
57    if (value->options().unknown_fields().field_count() > 0) return true;
58  }
59  return false;
60}
61}  // namespace
62
63EnumGenerator::EnumGenerator(const EnumDescriptor* descriptor,
64                             bool immutable_api,
65                             Context* context)
66  : descriptor_(descriptor), immutable_api_(immutable_api),
67    name_resolver_(context->GetNameResolver())  {
68  for (int i = 0; i < descriptor_->value_count(); i++) {
69    const EnumValueDescriptor* value = descriptor_->value(i);
70    const EnumValueDescriptor* canonical_value =
71      descriptor_->FindValueByNumber(value->number());
72
73    if (value == canonical_value) {
74      canonical_values_.push_back(value);
75    } else {
76      Alias alias;
77      alias.value = value;
78      alias.canonical_value = canonical_value;
79      aliases_.push_back(alias);
80    }
81  }
82}
83
84EnumGenerator::~EnumGenerator() {}
85
86void EnumGenerator::Generate(io::Printer* printer) {
87  WriteEnumDocComment(printer, descriptor_);
88  if (HasDescriptorMethods(descriptor_)) {
89    printer->Print(
90      "public enum $classname$\n"
91      "    implements com.google.protobuf.ProtocolMessageEnum {\n",
92      "classname", descriptor_->name());
93  } else {
94    printer->Print(
95      "public enum $classname$\n"
96      "    implements com.google.protobuf.Internal.EnumLite {\n",
97      "classname", descriptor_->name());
98  }
99  printer->Indent();
100
101  for (int i = 0; i < canonical_values_.size(); i++) {
102    map<string, string> vars;
103    vars["name"] = canonical_values_[i]->name();
104    vars["index"] = SimpleItoa(canonical_values_[i]->index());
105    vars["number"] = SimpleItoa(canonical_values_[i]->number());
106    WriteEnumValueDocComment(printer, canonical_values_[i]);
107    if (canonical_values_[i]->options().deprecated()) {
108      printer->Print("@java.lang.Deprecated\n");
109    }
110    printer->Print(vars,
111      "$name$($index$, $number$),\n");
112  }
113
114  printer->Print(
115    ";\n"
116    "\n");
117
118  // -----------------------------------------------------------------
119
120  for (int i = 0; i < aliases_.size(); i++) {
121    map<string, string> vars;
122    vars["classname"] = descriptor_->name();
123    vars["name"] = aliases_[i].value->name();
124    vars["canonical_name"] = aliases_[i].canonical_value->name();
125    WriteEnumValueDocComment(printer, aliases_[i].value);
126    printer->Print(vars,
127      "public static final $classname$ $name$ = $canonical_name$;\n");
128  }
129
130  for (int i = 0; i < descriptor_->value_count(); i++) {
131    map<string, string> vars;
132    vars["name"] = descriptor_->value(i)->name();
133    vars["number"] = SimpleItoa(descriptor_->value(i)->number());
134    WriteEnumValueDocComment(printer, descriptor_->value(i));
135    printer->Print(vars,
136      "public static final int $name$_VALUE = $number$;\n");
137  }
138  printer->Print("\n");
139
140  // -----------------------------------------------------------------
141
142  printer->Print(
143    "\n"
144    "public final int getNumber() { return value; }\n"
145    "\n"
146    "public static $classname$ valueOf(int value) {\n"
147    "  switch (value) {\n",
148    "classname", descriptor_->name());
149  printer->Indent();
150  printer->Indent();
151
152  for (int i = 0; i < canonical_values_.size(); i++) {
153    printer->Print(
154      "case $number$: return $name$;\n",
155      "name", canonical_values_[i]->name(),
156      "number", SimpleItoa(canonical_values_[i]->number()));
157  }
158
159  printer->Outdent();
160  printer->Outdent();
161  printer->Print(
162    "    default: return null;\n"
163    "  }\n"
164    "}\n"
165    "\n"
166    "public static com.google.protobuf.Internal.EnumLiteMap<$classname$>\n"
167    "    internalGetValueMap() {\n"
168    "  return internalValueMap;\n"
169    "}\n"
170    "private static com.google.protobuf.Internal.EnumLiteMap<$classname$>\n"
171    "    internalValueMap =\n"
172    "      new com.google.protobuf.Internal.EnumLiteMap<$classname$>() {\n"
173    "        public $classname$ findValueByNumber(int number) {\n"
174    "          return $classname$.valueOf(number);\n"
175    "        }\n"
176    "      };\n"
177    "\n",
178    "classname", descriptor_->name());
179
180  // -----------------------------------------------------------------
181  // Reflection
182
183  if (HasDescriptorMethods(descriptor_)) {
184    printer->Print(
185      "public final com.google.protobuf.Descriptors.EnumValueDescriptor\n"
186      "    getValueDescriptor() {\n"
187      "  return getDescriptor().getValues().get(index);\n"
188      "}\n"
189      "public final com.google.protobuf.Descriptors.EnumDescriptor\n"
190      "    getDescriptorForType() {\n"
191      "  return getDescriptor();\n"
192      "}\n"
193      "public static final com.google.protobuf.Descriptors.EnumDescriptor\n"
194      "    getDescriptor() {\n");
195
196    // TODO(kenton):  Cache statically?  Note that we can't access descriptors
197    //   at module init time because it wouldn't work with descriptor.proto, but
198    //   we can cache the value the first time getDescriptor() is called.
199    if (descriptor_->containing_type() == NULL) {
200      if (!MultipleJavaFiles(descriptor_->file(), immutable_api_)) {
201        printer->Print(
202          "  return $file$.getDescriptor().getEnumTypes().get($index$);\n",
203          "file", name_resolver_->GetClassName(descriptor_->file(),
204                                               immutable_api_),
205          "index", SimpleItoa(descriptor_->index()));
206      } else {
207        printer->Indent();
208        if (EnumHasCustomOptions(descriptor_)) {
209          // We need to load the immutable classes in order to parse custom
210          // options. However, since file level enums (no outer class) are
211          // shared by immutable code and mutable code, the immutable classes
212          // may not exist. So we try to use Java reflection to retrieve the
213          // descriptor from immutable classes.
214          printer->Print(
215            "try {\n"
216            "  java.lang.Class immutableFileClass =\n"
217            "      java.lang.Class.forName(\"$immutable_file_class_name$\");\n"
218            "  @java.lang.SuppressWarnings(\"unchecked\")\n"
219            "  java.lang.reflect.Method m =\n"
220            "      immutableFileClass.getMethod(\"getDescriptor\");\n"
221            "  com.google.protobuf.Descriptors.FileDescriptor file =\n"
222            "      (com.google.protobuf.Descriptors.FileDescriptor)\n"
223            "          m.invoke(immutableFileClass);\n"
224            "  return file.getEnumTypes().get($index$);\n"
225            "} catch (Exception e) {\n"
226            // Immutable classes cannot be found. Proceed as if custom options
227            // don't exist.
228            "}\n",
229            "immutable_file_class_name",
230            name_resolver_->GetImmutableClassName(descriptor_->file()),
231            "index", SimpleItoa(descriptor_->index()));
232        }
233        printer->Print(
234          "return $immutable_package$.$descriptor_class$.getDescriptor()\n"
235          "    .getEnumTypes().get($index$);\n",
236          "immutable_package", FileJavaPackage(descriptor_->file(), true),
237          "descriptor_class",
238          name_resolver_->GetDescriptorClassName(descriptor_->file()),
239          "index", SimpleItoa(descriptor_->index()));
240        printer->Outdent();
241      }
242    } else {
243      printer->Print(
244          "  return $parent$.$descriptor$.getEnumTypes().get($index$);\n",
245          "parent", name_resolver_->GetClassName(descriptor_->containing_type(),
246                                                 immutable_api_),
247          "descriptor", descriptor_->containing_type()->options()
248                        .no_standard_descriptor_accessor()
249                        ? "getDefaultInstance().getDescriptorForType()"
250                        : "getDescriptor()",
251          "index", SimpleItoa(descriptor_->index()));
252    }
253
254    printer->Print(
255      "}\n"
256      "\n"
257      "private static final $classname$[] VALUES = ",
258      "classname", descriptor_->name());
259
260    if (CanUseEnumValues()) {
261      // If the constants we are going to output are exactly the ones we
262      // have declared in the Java enum in the same order, then we can use
263      // the values() method that the Java compiler automatically generates
264      // for every enum.
265      printer->Print("values();\n");
266    } else {
267      printer->Print(
268        "{\n"
269        "  ");
270      for (int i = 0; i < descriptor_->value_count(); i++) {
271        printer->Print("$name$, ",
272          "name", descriptor_->value(i)->name());
273      }
274      printer->Print(
275          "\n"
276          "};\n");
277    }
278
279    printer->Print(
280      "\n"
281      "public static $classname$ valueOf(\n"
282      "    com.google.protobuf.Descriptors.EnumValueDescriptor desc) {\n"
283      "  if (desc.getType() != getDescriptor()) {\n"
284      "    throw new java.lang.IllegalArgumentException(\n"
285      "      \"EnumValueDescriptor is not for this type.\");\n"
286      "  }\n"
287      "  return VALUES[desc.getIndex()];\n"
288      "}\n"
289      "\n",
290      "classname", descriptor_->name());
291
292    // index is only used for reflection; lite implementation does not need it
293    printer->Print("private final int index;\n");
294  }
295
296  // -----------------------------------------------------------------
297
298  printer->Print(
299    "private final int value;\n\n"
300    "private $classname$(int index, int value) {\n",
301    "classname", descriptor_->name());
302  if (HasDescriptorMethods(descriptor_)) {
303    printer->Print("  this.index = index;\n");
304  }
305  printer->Print(
306    "  this.value = value;\n"
307    "}\n");
308
309  printer->Print(
310    "\n"
311    "// @@protoc_insertion_point(enum_scope:$full_name$)\n",
312    "full_name", descriptor_->full_name());
313
314  printer->Outdent();
315  printer->Print("}\n\n");
316}
317
318bool EnumGenerator::CanUseEnumValues() {
319  if (canonical_values_.size() != descriptor_->value_count()) {
320    return false;
321  }
322  for (int i = 0; i < descriptor_->value_count(); i++) {
323    if (descriptor_->value(i)->name() != canonical_values_[i]->name()) {
324      return false;
325    }
326  }
327  return true;
328}
329
330}  // namespace java
331}  // namespace compiler
332}  // namespace protobuf
333}  // namespace google
334