/* * Copyright 2014 Google Inc. All rights reserved. * * 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. */ // independent from idl_parser, since this code is not needed for most clients #include "flatbuffers/code_generators.h" #include "flatbuffers/flatbuffers.h" #include "flatbuffers/idl.h" #include "flatbuffers/util.h" #include "idl_namer.h" namespace flatbuffers { namespace java { namespace { static Namer::Config JavaDefaultConfig() { return { /*types=*/Case::kKeep, /*constants=*/Case::kScreamingSnake, /*methods=*/Case::kLowerCamel, /*functions=*/Case::kLowerCamel, /*fields=*/Case::kLowerCamel, /*variables=*/Case::kLowerCamel, /*variants=*/Case::kKeep, /*enum_variant_seperator=*/".", /*escape_keywords=*/Namer::Config::Escape::AfterConvertingCase, /*namespaces=*/Case::kKeep, /*namespace_seperator=*/".", /*object_prefix=*/"", /*object_suffix=*/"T", /*keyword_prefix=*/"", /*keyword_suffix=*/"_", /*filenames=*/Case::kKeep, /*directories=*/Case::kKeep, /*output_path=*/"", /*filename_suffix=*/"_generated", /*filename_extension=*/".java", }; } static std::set JavaKeywords() { return { "abstract", "continue", "for", "new", "switch", "assert", "default", "goto", "package", "synchronized", "boolean", "do", "if", "private", "this", "break", "double", "implements", "protected", "throw", "byte", "else", "import", "public", "throws", "case", "enum", "instanceof", "return", "transient", "catch", "extends", "int", "short", "try", "char", "final", "interface", "static", "void", "class", "finally", "long", "strictfp", "volatile", "const", "float", "native", "super", "while", }; } static const TypedFloatConstantGenerator JavaFloatGen("Double.", "Float.", "NaN", "POSITIVE_INFINITY", "NEGATIVE_INFINITY"); static const CommentConfig comment_config = { "/**", " *", " */", }; } // namespace class JavaGenerator : public BaseGenerator { struct FieldArrayLength { std::string name; int length; }; public: JavaGenerator(const Parser &parser, const std::string &path, const std::string &file_name) : BaseGenerator(parser, path, file_name, "", ".", "java"), cur_name_space_(nullptr), namer_(WithFlagOptions(JavaDefaultConfig(), parser.opts, path), JavaKeywords()) {} JavaGenerator &operator=(const JavaGenerator &); bool generate() { std::string one_file_code; cur_name_space_ = parser_.current_namespace_; for (auto it = parser_.enums_.vec.begin(); it != parser_.enums_.vec.end(); ++it) { std::string enumcode; auto &enum_def = **it; if (!parser_.opts.one_file) cur_name_space_ = enum_def.defined_namespace; GenEnum(enum_def, enumcode); if (parser_.opts.one_file) { one_file_code += enumcode; } else { if (!SaveType(enum_def.name, *enum_def.defined_namespace, enumcode, /* needs_includes= */ false)) return false; } if (parser_.opts.generate_object_based_api && enum_def.is_union) { enumcode = ""; GenEnum_ObjectAPI(enum_def, enumcode); auto class_name = namer_.Type(enum_def) + "Union"; if (parser_.opts.one_file) { one_file_code += enumcode; } else { if (!SaveType(class_name, *enum_def.defined_namespace, enumcode, /* needs_includes= */ false)) return false; } } } for (auto it = parser_.structs_.vec.begin(); it != parser_.structs_.vec.end(); ++it) { std::string declcode; auto &struct_def = **it; if (!parser_.opts.one_file) cur_name_space_ = struct_def.defined_namespace; GenStruct(struct_def, declcode, parser_.opts); if (parser_.opts.one_file) { one_file_code += declcode; } else { if (!SaveType(struct_def.name, *struct_def.defined_namespace, declcode, /* needs_includes= */ true)) return false; } if (parser_.opts.generate_object_based_api) { declcode = ""; GenStruct_ObjectAPI(struct_def, declcode); auto class_name = namer_.ObjectType(struct_def); if (parser_.opts.one_file) { one_file_code += declcode; } else { if (!SaveType(class_name, *struct_def.defined_namespace, declcode, /* needs_includes= */ true)) return false; } } } if (parser_.opts.one_file) { return SaveType(file_name_, *parser_.current_namespace_, one_file_code, /* needs_includes= */ true); } return true; } // Save out the generated code for a single class while adding // declaration boilerplate. bool SaveType(const std::string &defname, const Namespace &ns, const std::string &classcode, bool needs_includes) const { if (!classcode.length()) return true; std::string code; code = "// " + std::string(FlatBuffersGeneratedWarning()) + "\n\n"; const std::string namespace_name = FullNamespace(".", ns); if (!namespace_name.empty()) { code += "package " + namespace_name + ";"; code += "\n\n"; } if (needs_includes) { code += "import java.nio.*;\nimport java.lang.*;\nimport " "java.util.*;\nimport com.google.flatbuffers.*;\n"; if (parser_.opts.gen_nullable) { code += "\nimport javax.annotation.Nullable;\n"; } if (parser_.opts.java_checkerframework) { code += "\nimport org.checkerframework.dataflow.qual.Pure;\n"; } code += "\n"; } code += classcode; if (!namespace_name.empty()) code += ""; const std::string dirs = namer_.Directories(ns); EnsureDirExists(dirs); const std::string filename = dirs + namer_.File(defname, /*skips=*/SkipFile::Suffix); return SaveFile(filename.c_str(), code, false); } const Namespace *CurrentNameSpace() const { return cur_name_space_; } std::string GenNullableAnnotation(const Type &t) const { return parser_.opts.gen_nullable && !IsScalar(DestinationType(t, true).base_type) && t.base_type != BASE_TYPE_VECTOR ? " @Nullable " : ""; } std::string GenPureAnnotation(const Type &t) const { return parser_.opts.java_checkerframework && !IsScalar(DestinationType(t, true).base_type) ? " @Pure " : ""; } std::string GenTypeBasic(const Type &type) const { // clang-format off static const char * const java_typename[] = { #define FLATBUFFERS_TD(ENUM, IDLTYPE, CTYPE, JTYPE, ...) \ #JTYPE, FLATBUFFERS_GEN_TYPES(FLATBUFFERS_TD) #undef FLATBUFFERS_TD }; // clang-format on return java_typename[type.base_type]; } std::string GenTypePointer(const Type &type) const { switch (type.base_type) { case BASE_TYPE_STRING: return "String"; case BASE_TYPE_VECTOR: return GenTypeGet(type.VectorType()); case BASE_TYPE_STRUCT: return namer_.NamespacedType(*type.struct_def); case BASE_TYPE_UNION: FLATBUFFERS_FALLTHROUGH(); // else fall thru default: return "Table"; } } std::string GenTypeGet(const Type &type) const { return IsScalar(type.base_type) ? GenTypeBasic(type) : (IsArray(type) ? GenTypeGet(type.VectorType()) : GenTypePointer(type)); } // Find the destination type the user wants to receive the value in (e.g. // one size higher signed types for unsigned serialized values in Java). Type DestinationType(const Type &type, bool vectorelem) const { switch (type.base_type) { // We use int for both uchar/ushort, since that generally means less // casting than using short for uchar. case BASE_TYPE_UCHAR: return Type(BASE_TYPE_INT); case BASE_TYPE_USHORT: return Type(BASE_TYPE_INT); case BASE_TYPE_UINT: return Type(BASE_TYPE_LONG); case BASE_TYPE_ARRAY: case BASE_TYPE_VECTOR: if (vectorelem) return DestinationType(type.VectorType(), vectorelem); FLATBUFFERS_FALLTHROUGH(); // else fall thru default: return type; } } std::string GenOffsetType() const { return "int"; } std::string GenOffsetConstruct(const std::string &variable_name) const { return variable_name; } std::string GenVectorOffsetType() const { return "int"; } // Generate destination type name std::string GenTypeNameDest(const Type &type) const { return GenTypeGet(DestinationType(type, true)); } // Mask to turn serialized value into destination type value. std::string DestinationMask(const Type &type, bool vectorelem) const { switch (type.base_type) { case BASE_TYPE_UCHAR: return " & 0xFF"; case BASE_TYPE_USHORT: return " & 0xFFFF"; case BASE_TYPE_UINT: return " & 0xFFFFFFFFL"; case BASE_TYPE_VECTOR: if (vectorelem) return DestinationMask(type.VectorType(), vectorelem); FLATBUFFERS_FALLTHROUGH(); // else fall thru default: return ""; } } // Casts necessary to correctly read serialized data std::string DestinationCast(const Type &type) const { if (IsSeries(type)) { return DestinationCast(type.VectorType()); } else { // Cast necessary to correctly read serialized unsigned values. if (type.base_type == BASE_TYPE_UINT) return "(long)"; } return ""; } // Cast statements for mutator method parameters. // In Java, parameters representing unsigned numbers need to be cast down to // their respective type. For example, a long holding an unsigned int value // would be cast down to int before being put onto the buffer. std::string SourceCast(const Type &type, bool castFromDest) const { if (IsSeries(type)) { return SourceCast(type.VectorType(), castFromDest); } else { if (castFromDest) { if (type.base_type == BASE_TYPE_UINT) return "(int) "; else if (type.base_type == BASE_TYPE_USHORT) return "(short) "; else if (type.base_type == BASE_TYPE_UCHAR) return "(byte) "; } } return ""; } std::string SourceCast(const Type &type) const { return SourceCast(type, true); } std::string SourceCastBasic(const Type &type, bool castFromDest) const { return IsScalar(type.base_type) ? SourceCast(type, castFromDest) : ""; } std::string SourceCastBasic(const Type &type) const { return SourceCastBasic(type, true); } std::string GenEnumDefaultValue(const FieldDef &field) const { auto &value = field.value; FLATBUFFERS_ASSERT(value.type.enum_def); auto &enum_def = *value.type.enum_def; auto enum_val = enum_def.FindByValue(value.constant); return enum_val ? namer_.NamespacedEnumVariant(enum_def, *enum_val) : value.constant; } std::string GenDefaultValue(const FieldDef &field) const { auto &value = field.value; auto constant = field.IsScalarOptional() ? "0" : value.constant; auto longSuffix = "L"; switch (value.type.base_type) { case BASE_TYPE_BOOL: return constant == "0" ? "false" : "true"; case BASE_TYPE_ULONG: { // Converts the ulong into its bits signed equivalent uint64_t defaultValue = StringToUInt(constant.c_str()); return NumToString(static_cast(defaultValue)) + longSuffix; } case BASE_TYPE_UINT: case BASE_TYPE_LONG: return constant + longSuffix; default: if (IsFloat(value.type.base_type)) { if (field.IsScalarOptional()) { return value.type.base_type == BASE_TYPE_DOUBLE ? "0.0" : "0f"; } return JavaFloatGen.GenFloatConstant(field); } else { return constant; } } } std::string GenDefaultValueBasic(const FieldDef &field) const { auto &value = field.value; if (!IsScalar(value.type.base_type)) { return "0"; } return GenDefaultValue(field); } void GenEnum(EnumDef &enum_def, std::string &code) const { if (enum_def.generated) return; // Generate enum definitions of the form: // public static (final) int name = value; // In Java, we use ints rather than the Enum feature, because we want them // to map directly to how they're used in C/C++ and file formats. // That, and Java Enums are expensive, and not universally liked. GenComment(enum_def.doc_comment, &code, &comment_config); code += "@SuppressWarnings(\"unused\")\n"; if (enum_def.attributes.Lookup("private")) { // For Java, we leave the enum unmarked to indicate package-private } else { code += "public "; } code += "final class " + namer_.Type(enum_def); code += " {\n"; code += " private " + namer_.Type(enum_def) + "() { }\n"; for (auto it = enum_def.Vals().begin(); it != enum_def.Vals().end(); ++it) { auto &ev = **it; GenComment(ev.doc_comment, &code, &comment_config, " "); code += " public static final "; code += GenTypeBasic(DestinationType(enum_def.underlying_type, false)); code += " "; code += namer_.Variant(ev) + " = "; code += enum_def.ToString(ev); if (enum_def.underlying_type.base_type == BASE_TYPE_LONG || enum_def.underlying_type.base_type == BASE_TYPE_ULONG) { code += "L"; } code += ";\n"; } // Generate a string table for enum values. // Problem is, if values are very sparse that could generate really big // tables. Ideally in that case we generate a map lookup instead, but for // the moment we simply don't output a table at all. auto range = enum_def.Distance(); // Average distance between values above which we consider a table // "too sparse". Change at will. static const uint64_t kMaxSparseness = 5; if (range / static_cast(enum_def.size()) < kMaxSparseness && GenTypeBasic(DestinationType(enum_def.underlying_type, false)) != "long") { code += "\n public static final String"; code += "[] names = { "; const EnumVal *prev = enum_def.Vals().front(); for (auto it = enum_def.Vals().begin(); it != enum_def.Vals().end(); ++it) { const EnumVal &ev = **it; for (auto k = enum_def.Distance(prev, &ev); k > 1; --k) code += "\"\", "; prev = &ev; code += "\"" + namer_.Variant(ev) + "\", "; } code += "};\n\n"; code += " public static "; code += "String"; code += " name"; code += "(int e) { return names[e"; if (enum_def.MinValue()->IsNonZero()) code += " - " + namer_.Variant(enum_def.MinValue()->name); code += "]; }\n"; } // Close the class code += "}\n\n"; } // Returns the function name that is able to read a value of the given type. std::string GenGetter(const Type &type) const { switch (type.base_type) { case BASE_TYPE_STRING: return "__string"; case BASE_TYPE_STRUCT: return "__struct"; case BASE_TYPE_UNION: return "__union"; case BASE_TYPE_VECTOR: return GenGetter(type.VectorType()); case BASE_TYPE_ARRAY: return GenGetter(type.VectorType()); default: { std::string getter = "bb.get"; if (type.base_type == BASE_TYPE_BOOL) { getter = "0!=" + getter; } else if (GenTypeBasic(type) != "byte") { getter += ConvertCase(GenTypeBasic(type), Case::kUpperCamel); } return getter; } } } // Returns the function name that is able to read a value of the given type. std::string GenGetterForLookupByKey(flatbuffers::FieldDef *key_field, const std::string &data_buffer, const char *num = nullptr) const { auto type = key_field->value.type; auto dest_mask = DestinationMask(type, true); auto dest_cast = DestinationCast(type); auto getter = data_buffer + ".get"; if (GenTypeBasic(type) != "byte") { getter += ConvertCase(GenTypeBasic(type), Case::kUpperCamel); } getter = dest_cast + getter + "(" + GenOffsetGetter(key_field, num) + ")" + dest_mask; return getter; } // Direct mutation is only allowed for scalar fields. // Hence a setter method will only be generated for such fields. std::string GenSetter(const Type &type) const { if (IsScalar(type.base_type)) { std::string setter = "bb.put"; if (GenTypeBasic(type) != "byte" && type.base_type != BASE_TYPE_BOOL) { setter += ConvertCase(GenTypeBasic(type), Case::kUpperCamel); } return setter; } else { return ""; } } // Returns the method name for use with add/put calls. std::string GenMethod(const Type &type) const { return IsScalar(type.base_type) ? ConvertCase(GenTypeBasic(type), Case::kUpperCamel) : (IsStruct(type) ? "Struct" : "Offset"); } // Recursively generate arguments for a constructor, to deal with nested // structs. void GenStructArgs(const StructDef &struct_def, std::string &code, const char *nameprefix, size_t array_count = 0) const { for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; const auto &field_type = field.value.type; const auto array_field = IsArray(field_type); const auto &type = array_field ? field_type.VectorType() : DestinationType(field_type, false); const auto array_cnt = array_field ? (array_count + 1) : array_count; if (IsStruct(type)) { // Generate arguments for a struct inside a struct. To ensure names // don't clash, and to make it obvious these arguments are constructing // a nested struct, prefix the name with the field name. GenStructArgs(*field_type.struct_def, code, (nameprefix + (field.name + "_")).c_str(), array_cnt); } else { code += ", "; code += GenTypeNameDest(field.value.type); for (size_t i = 0; i < array_cnt; i++) code += "[]"; code += " "; code += nameprefix; code += namer_.Field(field); } } } // Recusively generate struct construction statements of the form: // builder.putType(name); // and insert manual padding. void GenStructBody(const StructDef &struct_def, std::string &code, const char *nameprefix, size_t index = 0, bool in_array = false) const { std::string indent((index + 1) * 2, ' '); code += indent + " builder.prep("; code += NumToString(struct_def.minalign) + ", "; code += NumToString(struct_def.bytesize) + ");\n"; for (auto it = struct_def.fields.vec.rbegin(); it != struct_def.fields.vec.rend(); ++it) { auto &field = **it; const auto &field_type = field.value.type; if (field.padding) { code += indent + " builder.pad("; code += NumToString(field.padding) + ");\n"; } if (IsStruct(field_type)) { GenStructBody(*field_type.struct_def, code, (nameprefix + (field.name + "_")).c_str(), index, in_array); } else { const auto &type = IsArray(field_type) ? field_type.VectorType() : field_type; const auto index_var = "_idx" + NumToString(index); if (IsArray(field_type)) { code += indent + " for (int " + index_var + " = "; code += NumToString(field_type.fixed_length); code += "; " + index_var + " > 0; " + index_var + "--) {\n"; in_array = true; } if (IsStruct(type)) { GenStructBody(*field_type.struct_def, code, (nameprefix + (field.name + "_")).c_str(), index + 1, in_array); } else { code += IsArray(field_type) ? " " : ""; code += indent + " builder.put"; code += GenMethod(type) + "("; code += SourceCast(type); auto argname = nameprefix + namer_.Variable(field); code += argname; size_t array_cnt = index + (IsArray(field_type) ? 1 : 0); for (size_t i = 0; in_array && i < array_cnt; i++) { code += "[_idx" + NumToString(i) + "-1]"; } code += ");\n"; } if (IsArray(field_type)) { code += indent + " }\n"; } } } } std::string GenOffsetGetter(flatbuffers::FieldDef *key_field, const char *num = nullptr) const { std::string key_offset = ""; key_offset += "__offset(" + NumToString(key_field->value.offset) + ", "; if (num) { key_offset += num; key_offset += ", _bb)"; } else { key_offset += "bb.capacity()"; key_offset += " - tableOffset, bb)"; } return key_offset; } std::string GenLookupKeyGetter(flatbuffers::FieldDef *key_field) const { std::string key_getter = " "; key_getter += "int tableOffset = "; key_getter += "__indirect(vectorLocation + 4 * (start + middle)"; key_getter += ", bb);\n "; if (IsString(key_field->value.type)) { key_getter += "int comp = "; key_getter += "compareStrings("; key_getter += GenOffsetGetter(key_field); key_getter += ", byteKey, bb);\n"; } else { auto get_val = GenGetterForLookupByKey(key_field, "bb"); key_getter += GenTypeNameDest(key_field->value.type) + " val = "; key_getter += get_val + ";\n"; key_getter += " int comp = val > key ? 1 : val < key ? -1 : 0;\n"; } return key_getter; } std::string GenKeyGetter(flatbuffers::FieldDef *key_field) const { std::string key_getter = ""; auto data_buffer = "_bb"; if (IsString(key_field->value.type)) { key_getter += " return "; key_getter += ""; key_getter += "compareStrings("; key_getter += GenOffsetGetter(key_field, "o1") + ", "; key_getter += GenOffsetGetter(key_field, "o2") + ", " + data_buffer + ")"; key_getter += ";"; } else { auto field_getter = GenGetterForLookupByKey(key_field, data_buffer, "o1"); key_getter += "\n " + GenTypeNameDest(key_field->value.type) + " val_1 = "; key_getter += field_getter + ";\n " + GenTypeNameDest(key_field->value.type); key_getter += " val_2 = "; field_getter = GenGetterForLookupByKey(key_field, data_buffer, "o2"); key_getter += field_getter + ";\n"; key_getter += " return val_1 > val_2 ? 1 : val_1 < val_2 ? -1 : 0;\n "; } return key_getter; } void GenStruct(StructDef &struct_def, std::string &code, const IDLOptions &opts) const { if (struct_def.generated) return; // Generate a struct accessor class, with methods of the form: // public type name() { return bb.getType(i + offset); } // or for tables of the form: // public type name() { // int o = __offset(offset); return o != 0 ? bb.getType(o + i) : default; // } GenComment(struct_def.doc_comment, &code, &comment_config); if (parser_.opts.gen_generated) { code += "@javax.annotation.Generated(value=\"flatc\")\n"; } code += "@SuppressWarnings(\"unused\")\n"; if (struct_def.attributes.Lookup("private")) { // For Java, we leave the struct unmarked to indicate package-private } else { code += "public "; } const auto struct_class = namer_.Type(struct_def); code += "final class " + struct_class; code += " extends "; code += struct_def.fixed ? "Struct" : "Table"; code += " {\n"; if (!struct_def.fixed) { // Generate version check method. // Force compile time error if not using the same version runtime. code += " public static void ValidateVersion() {"; code += " Constants."; code += "FLATBUFFERS_22_10_26(); "; code += "}\n"; // Generate a special accessor for the table that when used as the root // of a FlatBuffer const std::string method_name = namer_.LegacyJavaMethod2("getRootAs", struct_def, ""); const std::string method_signature = " public static " + struct_class + " " + method_name; // create convenience method that doesn't require an existing object code += method_signature + "(ByteBuffer _bb) "; code += "{ return " + method_name + "(_bb, new " + struct_class + "()); }\n"; // create method that allows object reuse code += method_signature + "(ByteBuffer _bb, " + struct_class + " obj) { "; code += "_bb.order(ByteOrder.LITTLE_ENDIAN); "; code += "return (obj.__assign(_bb.getInt(_bb."; code += "position()"; code += ") + _bb."; code += "position()"; code += ", _bb)); }\n"; if (parser_.root_struct_def_ == &struct_def) { if (parser_.file_identifier_.length()) { // Check if a buffer has the identifier. code += " public static "; code += "boolean " + namer_.LegacyJavaMethod2( "", struct_def, "BufferHasIdentifier(ByteBuffer _bb)") + " { return "; code += "__has_identifier(_bb, \""; code += parser_.file_identifier_; code += "\"); }\n"; } } } // Generate the __init method that sets the field in a pre-existing // accessor object. This is to allow object reuse. code += " public void __init(int _i, ByteBuffer _bb) "; code += "{ "; code += "__reset(_i, _bb); "; code += "}\n"; code += " public " + struct_class + " __assign(int _i, ByteBuffer _bb) "; code += "{ __init(_i, _bb); return this; }\n\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; GenComment(field.doc_comment, &code, &comment_config, " "); const std::string type_name = GenTypeGet(field.value.type); const std::string type_name_dest = GenTypeNameDest(field.value.type); const std::string dest_mask = DestinationMask(field.value.type, true); const std::string dest_cast = DestinationCast(field.value.type); const std::string src_cast = SourceCast(field.value.type); const std::string method_start = " public " + (field.IsRequired() ? "" : GenNullableAnnotation(field.value.type)) + GenPureAnnotation(field.value.type) + type_name_dest + " " + namer_.Field(field); const std::string obj = "obj"; // Most field accessors need to retrieve and test the field offset first, // this is the prefix code for that: auto offset_prefix = IsArray(field.value.type) ? " { return " : (" { int o = __offset(" + NumToString(field.value.offset) + "); return o != 0 ? "); // Generate the accessors that don't do object reuse. if (field.value.type.base_type == BASE_TYPE_STRUCT) { // Calls the accessor that takes an accessor object with a new object. code += method_start + "() { return "; code += namer_.Field(field); code += "(new "; code += type_name + "()); }\n"; } else if (IsSeries(field.value.type) && field.value.type.element == BASE_TYPE_STRUCT) { // Accessors for vectors of structs also take accessor objects, this // generates a variant without that argument. code += method_start + "(int j) { return "; code += namer_.Field(field); code += "(new " + type_name + "(), j); }\n"; } if (field.IsScalarOptional()) { code += GenOptionalScalarCheck(field); } std::string getter = dest_cast + GenGetter(field.value.type); code += method_start; std::string member_suffix = "; "; if (IsScalar(field.value.type.base_type)) { code += "()"; member_suffix += ""; if (struct_def.fixed) { code += " { return " + getter; code += "(bb_pos + "; code += NumToString(field.value.offset) + ")"; code += dest_mask; } else { code += offset_prefix + getter; code += "(o + bb_pos)" + dest_mask; code += " : "; code += GenDefaultValue(field); } } else { switch (field.value.type.base_type) { case BASE_TYPE_STRUCT: code += "(" + type_name + " obj)"; if (struct_def.fixed) { code += " { return " + obj + ".__assign("; code += "bb_pos + " + NumToString(field.value.offset) + ", "; code += "bb)"; } else { code += offset_prefix; code += obj + ".__assign("; code += field.value.type.struct_def->fixed ? "o + bb_pos" : "__indirect(o + bb_pos)"; code += ", bb) : null"; } break; case BASE_TYPE_STRING: code += "()"; member_suffix += ""; code += offset_prefix + getter + "(o + "; code += "bb_pos) : null"; break; case BASE_TYPE_ARRAY: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_VECTOR: { auto vectortype = field.value.type.VectorType(); code += "("; if (vectortype.base_type == BASE_TYPE_STRUCT) { code += type_name + " obj, "; getter = obj + ".__assign"; } else if (vectortype.base_type == BASE_TYPE_UNION) { code += type_name + " obj, "; } code += "int j)"; const auto body = offset_prefix + getter + "("; if (vectortype.base_type == BASE_TYPE_UNION) { code += body + "obj, "; } else { code += body; } std::string index; if (IsArray(field.value.type)) { index += "bb_pos + " + NumToString(field.value.offset) + " + "; } else { index += "__vector(o) + "; } index += "j * " + NumToString(InlineSize(vectortype)); if (vectortype.base_type == BASE_TYPE_STRUCT) { code += vectortype.struct_def->fixed ? index : "__indirect(" + index + ")"; code += ", bb"; } else { code += index; } code += ")" + dest_mask; if (!IsArray(field.value.type)) { code += " : "; code += field.value.type.element == BASE_TYPE_BOOL ? "false" : (IsScalar(field.value.type.element) ? "0" : "null"); } break; } case BASE_TYPE_UNION: code += "(" + type_name + " obj)" + offset_prefix + getter; code += "(obj, o + bb_pos) : null"; break; default: FLATBUFFERS_ASSERT(0); } } code += member_suffix; code += "}\n"; if (IsVector(field.value.type)) { code += " public int " + namer_.Field(field); code += "Length"; code += "()"; code += offset_prefix; code += "__vector_len(o) : 0; "; code += ""; code += "}\n"; // See if we should generate a by-key accessor. if (field.value.type.element == BASE_TYPE_STRUCT && !field.value.type.struct_def->fixed) { auto &sd = *field.value.type.struct_def; auto &fields = sd.fields.vec; for (auto kit = fields.begin(); kit != fields.end(); ++kit) { auto &key_field = **kit; if (key_field.key) { auto qualified_name = namer_.NamespacedType(sd); code += " public " + qualified_name + " "; code += namer_.Method(field) + "ByKey("; code += GenTypeNameDest(key_field.value.type) + " key)"; code += offset_prefix; code += qualified_name + ".__lookup_by_key("; code += "null, "; code += "__vector(o), key, "; code += "bb) : null; "; code += "}\n"; code += " public " + qualified_name + " "; code += namer_.Method(field) + "ByKey("; code += qualified_name + " obj, "; code += GenTypeNameDest(key_field.value.type) + " key)"; code += offset_prefix; code += qualified_name + ".__lookup_by_key(obj, "; code += "__vector(o), key, "; code += "bb) : null; "; code += "}\n"; break; } } } } // Generate the accessors for vector of structs with vector access object if (IsVector(field.value.type)) { std::string vector_type_name; const auto &element_base_type = field.value.type.VectorType().base_type; if (IsScalar(element_base_type)) { vector_type_name = ConvertCase(type_name, Case::kUpperCamel) + "Vector"; } else if (element_base_type == BASE_TYPE_STRING) { vector_type_name = "StringVector"; } else if (element_base_type == BASE_TYPE_UNION) { vector_type_name = "UnionVector"; } else { vector_type_name = type_name + ".Vector"; } auto vector_method_start = GenNullableAnnotation(field.value.type) + " public " + vector_type_name + " " + namer_.Field(field, "vector"); code += vector_method_start + "() { return "; code += namer_.Field(field, "vector"); code += "(new " + vector_type_name + "()); }\n"; code += vector_method_start + "(" + vector_type_name + " obj)"; code += offset_prefix + obj + ".__assign("; code += "__vector(o), "; if (!IsScalar(element_base_type)) { auto vectortype = field.value.type.VectorType(); code += NumToString(InlineSize(vectortype)) + ", "; } code += "bb) : null" + member_suffix + "}\n"; } // Generate a ByteBuffer accessor for strings & vectors of scalars. if ((IsVector(field.value.type) && IsScalar(field.value.type.VectorType().base_type)) || IsString(field.value.type)) { code += " public ByteBuffer "; code += namer_.Field(field); code += "AsByteBuffer() { return "; code += "__vector_as_bytebuffer("; code += NumToString(field.value.offset) + ", "; code += NumToString(IsString(field.value.type) ? 1 : InlineSize(field.value.type.VectorType())); code += "); }\n"; code += " public ByteBuffer "; code += namer_.Field(field); code += "InByteBuffer(ByteBuffer _bb) { return "; code += "__vector_in_bytebuffer(_bb, "; code += NumToString(field.value.offset) + ", "; code += NumToString(IsString(field.value.type) ? 1 : InlineSize(field.value.type.VectorType())); code += "); }\n"; } // generate object accessors if is nested_flatbuffer if (field.nested_flatbuffer) { auto nested_type_name = namer_.NamespacedType(*field.nested_flatbuffer); auto nested_method_name = namer_.Field(field) + "As" + field.nested_flatbuffer->name; auto get_nested_method_name = nested_method_name; code += " public " + nested_type_name + " "; code += nested_method_name + "() { return "; code += get_nested_method_name + "(new " + nested_type_name + "()); }\n"; code += " public " + nested_type_name + " "; code += get_nested_method_name + "("; code += nested_type_name + " obj"; code += ") { int o = __offset("; code += NumToString(field.value.offset) + "); "; code += "return o != 0 ? " + obj + ".__assign("; code += ""; code += "__indirect(__vector(o)), "; code += "bb) : null; }\n"; } // Generate mutators for scalar fields or vectors of scalars. if (parser_.opts.mutable_buffer) { auto is_series = (IsSeries(field.value.type)); const auto &underlying_type = is_series ? field.value.type.VectorType() : field.value.type; // Boolean parameters have to be explicitly converted to byte // representation. auto setter_parameter = underlying_type.base_type == BASE_TYPE_BOOL ? "(byte)(" + field.name + " ? 1 : 0)" : field.name; // A vector mutator also needs the index of the vector element it should // mutate. auto mutator_params = (is_series ? "(int j, " : "(") + GenTypeNameDest(underlying_type) + " " + field.name + ") { "; auto setter_index = is_series ? (IsArray(field.value.type) ? "bb_pos + " + NumToString(field.value.offset) : "__vector(o)") + +" + j * " + NumToString(InlineSize(underlying_type)) : (struct_def.fixed ? "bb_pos + " + NumToString(field.value.offset) : "o + bb_pos"); if (IsScalar(underlying_type.base_type) && !IsUnion(field.value.type)) { code += " public "; code += struct_def.fixed ? "void " : "boolean "; code += namer_.Method("mutate", field); code += mutator_params; if (struct_def.fixed) { code += GenSetter(underlying_type) + "(" + setter_index + ", "; code += src_cast + setter_parameter + "); }\n"; } else { code += "int o = __offset("; code += NumToString(field.value.offset) + ");"; code += " if (o != 0) { " + GenSetter(underlying_type); code += "(" + setter_index + ", " + src_cast + setter_parameter + "); return true; } else { return false; } }\n"; } } } if (parser_.opts.java_primitive_has_method && IsScalar(field.value.type.base_type) && !struct_def.fixed) { auto vt_offset_constant = " public static final int VT_" + namer_.Constant(field) + " = " + NumToString(field.value.offset) + ";"; code += vt_offset_constant; code += "\n"; } } code += "\n"; auto struct_has_create = false; std::set field_has_create_set; flatbuffers::FieldDef *key_field = nullptr; if (struct_def.fixed) { struct_has_create = true; // create a struct constructor function code += " public static " + GenOffsetType() + " "; code += "create"; code += struct_class + "(FlatBufferBuilder builder"; GenStructArgs(struct_def, code, ""); code += ") {\n"; GenStructBody(struct_def, code, ""); code += " return "; code += GenOffsetConstruct("builder." + std::string("offset()")); code += ";\n }\n"; } else { // Generate a method that creates a table in one go. This is only possible // when the table has no struct fields, since those have to be created // inline, and there's no way to do so in Java. bool has_no_struct_fields = true; int num_fields = 0; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; if (IsStruct(field.value.type)) { has_no_struct_fields = false; } else { num_fields++; } } // JVM specifications restrict default constructor params to be < 255. // Longs and doubles take up 2 units, so we set the limit to be < 127. if (has_no_struct_fields && num_fields && num_fields < 127) { struct_has_create = true; // Generate a table constructor of the form: // public static int createName(FlatBufferBuilder builder, args...) code += " public static " + GenOffsetType() + " "; code += namer_.LegacyJavaMethod2("create", struct_def, ""); code += "(FlatBufferBuilder builder"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; auto field_name = namer_.Field(field); if (field.deprecated) continue; code += ",\n "; code += GenTypeBasic(DestinationType(field.value.type, false)); code += " "; code += field_name; if (!IsScalar(field.value.type.base_type)) code += "Offset"; } code += ") {\n builder."; code += "startTable("; code += NumToString(struct_def.fields.vec.size()) + ");\n"; for (size_t size = struct_def.sortbysize ? sizeof(largest_scalar_t) : 1; size; size /= 2) { for (auto it = struct_def.fields.vec.rbegin(); it != struct_def.fields.vec.rend(); ++it) { auto &field = **it; auto field_name = namer_.Field(field); if (!field.deprecated && (!struct_def.sortbysize || size == SizeOf(field.value.type.base_type))) { code += " " + struct_class + "."; code += namer_.Method("add", field) + "(builder, " + field_name; if (!IsScalar(field.value.type.base_type)) code += "Offset"; code += ");\n"; } } } code += " return " + struct_class + "."; code += namer_.LegacyJavaMethod2("end", struct_def, ""); code += "(builder);\n }\n\n"; } // Generate a set of static methods that allow table construction, // of the form: // public static void addName(FlatBufferBuilder builder, short name) // { builder.addShort(id, name, default); } // Unlike the Create function, these always work. code += " public static void start"; code += struct_class; code += "(FlatBufferBuilder builder) { builder."; code += "startTable("; code += NumToString(struct_def.fields.vec.size()) + "); }\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; code += " public static void " + namer_.Method("add", field); code += "(FlatBufferBuilder builder, "; code += GenTypeBasic(DestinationType(field.value.type, false)); auto argname = namer_.Field(field); if (!IsScalar(field.value.type.base_type)) argname += "Offset"; code += " " + argname + ") { builder.add"; code += GenMethod(field.value.type) + "("; if (field.key) { // field has key attribute, so always need to exist // even if its value is equal to default. // Generated code will bypass default checking // resulting in { builder.addShort(name); slot(id); } key_field = &field; code += SourceCastBasic(field.value.type); code += argname; code += "); builder.slot(" + NumToString(it - struct_def.fields.vec.begin()) + "); }\n"; } else { code += NumToString(it - struct_def.fields.vec.begin()) + ", "; code += SourceCastBasic(field.value.type); code += argname; code += ", "; code += SourceCastBasic(field.value.type); code += GenDefaultValue(field); code += "); }\n"; } if (IsVector(field.value.type)) { auto vector_type = field.value.type.VectorType(); auto alignment = InlineAlignment(vector_type); auto elem_size = InlineSize(vector_type); if (!IsStruct(vector_type)) { field_has_create_set.insert(&field); // generate a method to create a vector from a java array. if ((vector_type.base_type == BASE_TYPE_CHAR || vector_type.base_type == BASE_TYPE_UCHAR)) { // Handle byte[] and ByteBuffers separately for Java code += " public static " + GenVectorOffsetType() + " "; code += namer_.Method("create", field); code += "Vector(FlatBufferBuilder builder, byte[] data) "; code += "{ return builder.createByteVector(data); }\n"; code += " public static " + GenVectorOffsetType() + " "; code += namer_.Method("create", field); code += "Vector(FlatBufferBuilder builder, ByteBuffer data) "; code += "{ return builder.createByteVector(data); }\n"; } else { code += " public static " + GenVectorOffsetType() + " "; code += namer_.Method("create", field); code += "Vector(FlatBufferBuilder builder, "; code += GenTypeBasic(DestinationType(vector_type, false)) + "[] data) "; code += "{ builder.startVector("; code += NumToString(elem_size); code += ", data.length, "; code += NumToString(alignment); code += "); for (int i = data."; code += "length - 1; i >= 0; i--) builder."; code += "add"; code += GenMethod(vector_type); code += "("; code += SourceCastBasic(vector_type); code += "data[i]"; code += "); return "; code += "builder.endVector(); }\n"; } } // Generate a method to start a vector, data to be added manually // after. code += " public static void " + namer_.Method("start", field); code += "Vector(FlatBufferBuilder builder, int numElems) "; code += "{ builder.startVector("; code += NumToString(elem_size); code += ", numElems, " + NumToString(alignment); code += "); }\n"; } } code += " public static " + GenOffsetType() + " "; code += namer_.LegacyJavaMethod2("end", struct_def, ""); code += "(FlatBufferBuilder builder) {\n int o = builder."; code += "endTable();\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (!field.deprecated && field.IsRequired()) { code += " builder.required(o, "; code += NumToString(field.value.offset); code += "); // " + field.name + "\n"; } } code += " return " + GenOffsetConstruct("o") + ";\n }\n"; if (parser_.root_struct_def_ == &struct_def) { std::string size_prefix[] = { "", "SizePrefixed" }; for (int i = 0; i < 2; ++i) { code += " public static void "; code += namer_.LegacyJavaMethod2("finish" + size_prefix[i], struct_def, "Buffer"); code += "(FlatBufferBuilder builder, " + GenOffsetType(); code += " offset) {"; code += " builder.finish" + size_prefix[i] + "(offset"; if (parser_.file_identifier_.length()) code += ", \"" + parser_.file_identifier_ + "\""; code += "); }\n"; } } } // Only generate key compare function for table, // because `key_field` is not set for struct if (struct_def.has_key && !struct_def.fixed) { FLATBUFFERS_ASSERT(key_field); code += "\n @Override\n protected int keysCompare("; code += "Integer o1, Integer o2, ByteBuffer _bb) {"; code += GenKeyGetter(key_field); code += " }\n"; code += "\n public static " + struct_class; code += " __lookup_by_key("; code += struct_class + " obj, "; code += "int vectorLocation, "; code += GenTypeNameDest(key_field->value.type); code += " key, ByteBuffer bb) {\n"; if (IsString(key_field->value.type)) { code += " byte[] byteKey = "; code += "key.getBytes(java.nio.charset.StandardCharsets.UTF_8);\n"; } code += " int span = "; code += "bb.getInt(vectorLocation - 4);\n"; code += " int start = 0;\n"; code += " while (span != 0) {\n"; code += " int middle = span / 2;\n"; code += GenLookupKeyGetter(key_field); code += " if (comp > 0) {\n"; code += " span = middle;\n"; code += " } else if (comp < 0) {\n"; code += " middle++;\n"; code += " start += middle;\n"; code += " span -= middle;\n"; code += " } else {\n"; code += " return "; code += "(obj == null ? new " + struct_class + "() : obj)"; code += ".__assign(tableOffset, bb);\n"; code += " }\n }\n"; code += " return null;\n"; code += " }\n"; } GenVectorAccessObject(struct_def, code); if (opts.generate_object_based_api) { GenPackUnPack_ObjectAPI(struct_def, code, opts, struct_has_create, field_has_create_set); } code += "}\n\n"; } std::string GenOptionalScalarCheck(FieldDef &field) const { if (!field.IsScalarOptional()) return ""; return " public boolean " + namer_.Method("has", field) + "() { return 0 != __offset(" + NumToString(field.value.offset) + "); }\n"; } void GenVectorAccessObject(StructDef &struct_def, std::string &code) const { // Generate a vector of structs accessor class. code += "\n"; code += " "; if (!struct_def.attributes.Lookup("private")) code += "public "; code += "static "; code += "final "; code += "class Vector extends "; code += "BaseVector {\n"; // Generate the __assign method that sets the field in a pre-existing // accessor object. This is to allow object reuse. std::string method_indent = " "; code += method_indent + "public Vector "; code += "__assign(int _vector, int _element_size, ByteBuffer _bb) { "; code += "__reset(_vector, _element_size, _bb); return this; }\n\n"; auto type_name = namer_.Type(struct_def); auto method_start = method_indent + "public " + type_name + " get"; // Generate the accessors that don't do object reuse. code += method_start + "(int j) { return get"; code += "(new " + type_name + "(), j); }\n"; code += method_start + "(" + type_name + " obj, int j) { "; code += " return obj.__assign("; std::string index = "__element(j)"; code += struct_def.fixed ? index : "__indirect(" + index + ", bb)"; code += ", bb); }\n"; // See if we should generate a by-key accessor. if (!struct_def.fixed) { auto &fields = struct_def.fields.vec; for (auto kit = fields.begin(); kit != fields.end(); ++kit) { auto &key_field = **kit; if (key_field.key) { auto nullable_annotation = parser_.opts.gen_nullable ? "@Nullable " : ""; code += method_indent + nullable_annotation; code += "public " + type_name + " "; code += "getByKey("; code += GenTypeNameDest(key_field.value.type) + " key) { "; code += " return __lookup_by_key(null, "; code += "__vector(), key, "; code += "bb); "; code += "}\n"; code += method_indent + nullable_annotation; code += "public " + type_name + " "; code += "getByKey("; code += type_name + " obj, "; code += GenTypeNameDest(key_field.value.type) + " key) { "; code += " return __lookup_by_key(obj, "; code += "__vector(), key, "; code += "bb); "; code += "}\n"; break; } } } code += " }\n"; } void GenEnum_ObjectAPI(EnumDef &enum_def, std::string &code) const { if (enum_def.generated) return; code += "import com.google.flatbuffers.FlatBufferBuilder;\n\n"; if (!enum_def.attributes.Lookup("private")) { code += "public "; } auto union_name = namer_.Type(enum_def) + "Union"; auto union_type = GenTypeBasic(DestinationType(enum_def.underlying_type, false)); code += "class " + union_name + " {\n"; // Type code += " private " + union_type + " type;\n"; // Value code += " private Object value;\n"; code += "\n"; // getters and setters code += " public " + union_type + " getType() { return type; }\n\n"; code += " public void setType(" + union_type + " type) { this.type = type; }\n\n"; code += " public Object getValue() { return value; }\n\n"; code += " public void setValue(Object value) { this.value = value; }\n\n"; // Constructor code += " public " + union_name + "() {\n"; code += " this.type = " + namer_.EnumVariant(enum_def, *enum_def.Vals()[0]) + ";\n"; code += " this.value = null;\n"; code += " }\n\n"; // As for (auto it = enum_def.Vals().begin(); it != enum_def.Vals().end(); ++it) { auto &ev = **it; if (ev.union_type.base_type == BASE_TYPE_NONE) continue; auto type_name = GenTypeGet_ObjectAPI(ev.union_type, false, true); if (ev.union_type.base_type == BASE_TYPE_STRUCT && ev.union_type.struct_def->attributes.Lookup("private")) { code += " "; } else { code += " public "; } code += type_name + " as" + ev.name + "() { return (" + type_name + ") value; }\n"; } code += "\n"; // pack() code += " public static int pack(FlatBufferBuilder builder, " + union_name + " _o) {\n"; code += " switch (_o.type) {\n"; for (auto it = enum_def.Vals().begin(); it != enum_def.Vals().end(); ++it) { auto &ev = **it; if (ev.union_type.base_type == BASE_TYPE_NONE) { continue; } else { code += " case " + namer_.EnumVariant(enum_def, ev) + ": return "; if (IsString(ev.union_type)) { code += "builder.createString(_o.as" + ev.name + "());\n"; } else { code += GenTypeGet(ev.union_type) + ".pack(builder, _o.as" + ev.name + "());\n"; } } } code += " default: return 0;\n"; code += " }\n"; code += " }\n"; code += "}\n\n"; } void GenUnionUnPack_ObjectAPI(const EnumDef &enum_def, std::string &code, const std::string &type_name, const std::string &field_name, bool is_vector) const { const std::string variable_type = is_vector ? type_name.substr(0, type_name.length() - 2) : type_name; const std::string variable_name = "_" + namer_.Variable("o", field_name) + (is_vector ? "Element" : ""); const std::string type_params = is_vector ? "_j" : ""; const std::string value_params = is_vector ? ", _j" : ""; const std::string indent = (is_vector ? " " : " "); code += indent + variable_type + " " + variable_name + " = new " + variable_type + "();\n"; code += indent + GenTypeBasic(DestinationType(enum_def.underlying_type, false)) + " " + variable_name + "Type = " + field_name + "Type(" + type_params + ");\n"; code += indent + variable_name + ".setType(" + variable_name + "Type);\n"; code += indent + "Table " + variable_name + "Value;\n"; code += indent + "switch (" + variable_name + "Type) {\n"; for (auto eit = enum_def.Vals().begin(); eit != enum_def.Vals().end(); ++eit) { auto &ev = **eit; if (ev.union_type.base_type == BASE_TYPE_NONE) { continue; } else { if (ev.union_type.base_type == BASE_TYPE_STRING || (ev.union_type.base_type == BASE_TYPE_STRUCT && ev.union_type.struct_def->fixed)) { continue; // This branch is due to bad implemantation of Unions in // Java which doesn't handle non Table types. Should be // deleted when issue #6561 is fixed. } code += indent + " case " + namer_.NamespacedEnumVariant(enum_def, ev) + ":\n"; auto actual_type = GenTypeGet(ev.union_type); code += indent + " " + variable_name + "Value = " + field_name + "(new " + actual_type + "()" + value_params + ");\n"; code += indent + " " + variable_name + ".setValue(" + variable_name + "Value != null ? ((" + actual_type + ") " + variable_name + "Value).unpack() : null);\n"; code += indent + " break;\n"; } } code += indent + " default: break;\n"; code += indent + "}\n"; if (is_vector) { code += indent + "_" + namer_.Variable("o", field_name) + "[_j] = " + variable_name + ";\n"; } } void GenPackUnPack_ObjectAPI( StructDef &struct_def, std::string &code, const IDLOptions &opts, bool struct_has_create, const std::set &field_has_create) const { auto struct_name = namer_.ObjectType(struct_def); // unpack() code += " public " + struct_name + " unpack() {\n"; code += " " + struct_name + " _o = new " + struct_name + "();\n"; code += " unpackTo(_o);\n"; code += " return _o;\n"; code += " }\n"; // unpackTo() code += " public void unpackTo(" + struct_name + " _o) {\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { const auto &field = **it; if (field.deprecated) continue; if (field.value.type.base_type == BASE_TYPE_UTYPE) continue; if (field.value.type.element == BASE_TYPE_UTYPE) continue; const auto accessor = namer_.Method(field); const auto variable = "_" + namer_.Variable("o", field); const auto get_field = namer_.Method("get", field); const auto set_field = namer_.Method("set", field); auto type_name = GenTypeGet_ObjectAPI(field.value.type, false, true); if (field.IsScalarOptional()) type_name = ConvertPrimitiveTypeToObjectWrapper_ObjectAPI(type_name); auto start = " " + type_name + " " + variable + " = "; auto call_setter = true; switch (field.value.type.base_type) { case BASE_TYPE_STRUCT: { auto fixed = struct_def.fixed && field.value.type.struct_def->fixed; if (fixed) { code += " " + accessor + "().unpackTo(_o." + get_field + "());\n"; } else { code += " if (" + accessor + "() != null) "; if (field.value.type.struct_def->fixed) { code += accessor + "().unpackTo(_o." + get_field + "());\n"; } else { code += "_o." + set_field + "(" + accessor + "().unpack());\n"; } code += " else _o." + set_field + "(null);\n"; } call_setter = false; break; } case BASE_TYPE_ARRAY: { auto length_str = NumToString(field.value.type.fixed_length); auto unpack_method = field.value.type.struct_def == nullptr ? "" : ".unpack()"; code += start + "_o." + get_field + "();\n"; code += " for (int _j = 0; _j < " + length_str + "; ++_j) { " + variable + "[_j] = " + accessor + "(_j)" + unpack_method + "; }\n"; call_setter = false; break; } case BASE_TYPE_VECTOR: if (field.value.type.element == BASE_TYPE_UNION) { code += start + "new " + GenConcreteTypeGet_ObjectAPI(field.value.type) .substr(0, type_name.length() - 1) + accessor + "Length()];\n"; code += " for (int _j = 0; _j < " + accessor + "Length(); ++_j) {\n"; GenUnionUnPack_ObjectAPI(*field.value.type.enum_def, code, type_name, accessor, true); code += " }\n"; } else if (field.value.type.element != BASE_TYPE_UTYPE) { auto fixed = field.value.type.struct_def == nullptr; const auto length_accessor = namer_.Method(field, "length"); code += start + "new " + GenConcreteTypeGet_ObjectAPI(field.value.type) .substr(0, type_name.length() - 1) + length_accessor + "()];\n"; code += " for (int _j = 0; _j < " + length_accessor + "(); ++_j) {"; code += variable + "[_j] = "; if (fixed) { code += accessor + "(_j)"; } else { code += "(" + accessor + "(_j) != null ? " + accessor + "(_j).unpack() : null)"; } code += ";}\n"; } break; case BASE_TYPE_UTYPE: break; case BASE_TYPE_UNION: { GenUnionUnPack_ObjectAPI(*field.value.type.enum_def, code, type_name, accessor, false); break; } default: { if (field.IsScalarOptional()) { code += start + namer_.Method("has", field) + "() ? " + accessor + "() : null;\n"; } else { code += start + accessor + "();\n"; } break; } } if (call_setter) { code += " _o." + set_field + "(" + variable + ");\n"; } } code += " }\n"; // pack() code += " public static " + GenOffsetType() + " pack(FlatBufferBuilder builder, " + struct_name + " _o) {\n"; code += " if (_o == null) return 0;\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; const auto field_name = namer_.Field(field); const auto variable = "_" + namer_.Variable("o", field); const auto get_field = namer_.Method("get", field); // pre switch (field.value.type.base_type) { case BASE_TYPE_STRUCT: { if (!field.value.type.struct_def->fixed) { code += " " + GenOffsetType() + " _" + namer_.Variable(field) + " = _o." + get_field + "() == null ? 0 : " + GenTypeGet(field.value.type) + ".pack(builder, _o." + get_field + "());\n"; } else if (struct_def.fixed && struct_has_create) { std::vector array_lengths; FieldArrayLength tmp_array_length = { field.name, field.value.type.fixed_length, }; array_lengths.push_back(tmp_array_length); GenStructPackDecl_ObjectAPI(*field.value.type.struct_def, array_lengths, code); } break; } case BASE_TYPE_STRING: { code += " int _" + field_name + " = _o." + get_field + "() == null ? 0 : " "builder.createString(_o." + get_field + "());\n"; break; } case BASE_TYPE_VECTOR: { if (field_has_create.find(&field) != field_has_create.end()) { auto property_name = field_name; auto gen_for_loop = true; std::string array_name = "__" + field_name; std::string array_type = ""; std::string element_type = ""; std::string to_array = ""; switch (field.value.type.element) { case BASE_TYPE_STRING: { array_type = "int"; element_type = "String"; to_array = "builder.createString(_e)"; break; } case BASE_TYPE_STRUCT: array_type = "int"; element_type = GenTypeGet_ObjectAPI(field.value.type, true, true); ; to_array = GenTypeGet(field.value.type) + ".pack(builder, _e)"; break; case BASE_TYPE_UTYPE: property_name = field_name.substr(0, field_name.size() - 4); array_type = GenTypeBasic(DestinationType( field.value.type.enum_def->underlying_type, false)); element_type = field.value.type.enum_def->name + "Union"; to_array = "_o." + namer_.Method("get", property_name) + "()[_j].getType()"; break; case BASE_TYPE_UNION: array_type = "int"; element_type = namer_.NamespacedType(*field.value.type.enum_def) + "Union"; to_array = element_type + ".pack(builder, _o." + namer_.Method("get", property_name) + "()[_j])"; break; case BASE_TYPE_UCHAR: // TODO this branch of the switch is due to // inconsistent behavior in unsigned byte. // Read further at Issue #6574. array_type = "byte"; element_type = "int"; to_array = "(byte) _e"; break; default: gen_for_loop = false; array_name = "_o." + namer_.Method("get", property_name) + "()"; array_type = GenTypeNameDest(field.value.type); element_type = array_type; to_array = "_e"; break; } code += " int _" + field_name + " = 0;\n"; code += " if (_o." + namer_.Method("get", property_name) + "() != null) {\n"; if (gen_for_loop) { code += " " + array_type + "[] " + array_name + " = new " + array_type + "[_o." + namer_.Method("get", property_name) + "().length];\n"; code += " int _j = 0;\n"; code += " for (" + element_type + " _e : _o." + namer_.Method("get", property_name) + "()) { "; code += array_name + "[_j] = " + to_array + "; _j++;}\n"; } code += " _" + field_name + " = " + namer_.Method("create", field) + "Vector(builder, " + array_name + ");\n"; code += " }\n"; } else { auto type_name = GenTypeGet(field.value.type); auto element_type_name = GenTypeGet_ObjectAPI(field.value.type, true, true); auto pack_method = field.value.type.struct_def == nullptr ? "builder.add" + GenMethod(field.value.type.VectorType()) + "(" + variable + "[_j]);" : "_unused_offset = " + type_name + ".pack(builder, " + variable + "[_j]);"; code += " int _" + field_name + " = 0;\n"; code += " " + element_type_name + "[] " + variable + " = _o." + get_field + "();\n"; code += " if (" + variable + " != null) {\n"; if (field.value.type.struct_def != nullptr) { code += " int _unused_offset = 0;\n"; } code += " " + namer_.Method("start", field) + "Vector(builder, " + variable + ".length);\n"; code += " for (int _j = " + variable + ".length - 1; _j >=0; _j--) { "; code += pack_method + "}\n"; code += " _" + field_name + " = builder.endVector();\n"; code += " }\n"; } break; } case BASE_TYPE_ARRAY: { if (field.value.type.struct_def != nullptr) { std::vector array_lengths; FieldArrayLength tmp_array_length = { field.name, field.value.type.fixed_length, }; array_lengths.push_back(tmp_array_length); GenStructPackDecl_ObjectAPI(*field.value.type.struct_def, array_lengths, code); } else { code += " " + GenTypeGet_ObjectAPI(field.value.type, false, true) + " _" + field_name + " = _o." + get_field + "();\n"; } break; } case BASE_TYPE_UNION: { code += " " + GenTypeBasic(DestinationType( field.value.type.enum_def->underlying_type, false)) + " _" + field_name + "Type = _o." + get_field + "() == null ? " + namer_.NamespacedType(*field.value.type.enum_def) + ".NONE : " + "_o." + get_field + "().getType();\n"; code += " " + GenOffsetType() + " _" + field_name + " = _o." + get_field + "() == null ? 0 : " + namer_.NamespacedType(*field.value.type.enum_def) + "Union.pack(builder, _o." + get_field + "());\n"; break; } default: break; } } if (struct_has_create) { // Create code += " return " + namer_.LegacyJavaMethod2("create", struct_def, "") + "(\n"; code += " builder"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; const auto field_name = namer_.Field(field); const auto get_field = namer_.Method("get", field); switch (field.value.type.base_type) { case BASE_TYPE_STRUCT: { if (struct_def.fixed) { GenStructPackCall_ObjectAPI(*field.value.type.struct_def, code, " _" + field_name + "_"); } else { code += ",\n"; if (field.value.type.struct_def->fixed) { if (opts.generate_object_based_api) code += " _o." + field_name; else // Seems like unreachable code code += " " + GenTypeGet(field.value.type) + ".Pack(builder, _o." + field_name + ")"; } else { code += " _" + field_name; } } break; } case BASE_TYPE_ARRAY: { if (field.value.type.struct_def != nullptr) { GenStructPackCall_ObjectAPI(*field.value.type.struct_def, code, " _" + field_name + "_"); } else { code += ",\n"; code += " _" + field_name; } break; } case BASE_TYPE_UNION: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_UTYPE: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_STRING: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_VECTOR: { code += ",\n"; code += " _" + field_name; break; } default: // scalar code += ",\n"; code += " _o." + get_field + "()"; break; } } code += ");\n"; } else { // Start, End code += " " + namer_.LegacyJavaMethod2("start", struct_def, "") + "(builder);\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; if (field.deprecated) continue; const auto arg = "_" + namer_.Variable(field); const auto get_field = namer_.Method("get", field); const auto add_field = namer_.Method("add", field); switch (field.value.type.base_type) { case BASE_TYPE_STRUCT: { if (field.value.type.struct_def->fixed) { code += " " + add_field + "(builder, " + GenTypeGet(field.value.type) + ".pack(builder, _o." + get_field + "()));\n"; } else { code += " " + add_field + "(builder, " + arg + ");\n"; } break; } case BASE_TYPE_STRING: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_ARRAY: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_VECTOR: { code += " " + add_field + "(builder, " + arg + ");\n"; break; } case BASE_TYPE_UTYPE: break; case BASE_TYPE_UNION: { code += " " + add_field + "Type(builder, " + arg + "Type);\n"; code += " " + add_field + "(builder, " + arg + ");\n"; break; } // scalar default: { if (field.IsScalarOptional()) { code += " if (_o." + get_field + "() != null) { " + add_field + "(builder, _o." + get_field + "()); }\n"; } else { code += " " + add_field + "(builder, _o." + get_field + "());\n"; } break; } } } code += " return " + namer_.LegacyJavaMethod2("end", struct_def, "") + "(builder);\n"; } code += " }\n"; } void GenStructPackDecl_ObjectAPI(const StructDef &struct_def, std::vector &array_lengths, std::string &code) const { for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { const FieldDef &field = **it; const bool is_array = IsArray(field.value.type); const Type &field_type = is_array ? field.value.type.VectorType() : field.value.type; FieldArrayLength tmp_array_length = { field.name, field_type.fixed_length, }; array_lengths.push_back(tmp_array_length); if (field_type.struct_def != nullptr) { GenStructPackDecl_ObjectAPI(*field_type.struct_def, array_lengths, code); } else { std::vector array_only_lengths; for (size_t i = 0; i < array_lengths.size(); ++i) { if (array_lengths[i].length > 0) { array_only_lengths.push_back(array_lengths[i]); } } std::string name; for (size_t i = 0; i < array_lengths.size(); ++i) { name += "_" + namer_.Variable(array_lengths[i].name); } code += " " + GenTypeBasic(field_type); if (array_only_lengths.size() > 0) { for (size_t i = 0; i < array_only_lengths.size(); ++i) { code += "[]"; } code += " " + name + " = "; code += "new " + GenTypeBasic(field_type) + "["; for (size_t i = 0; i < array_only_lengths.size(); ++i) { if (i != 0) { code += "]["; } code += NumToString(array_only_lengths[i].length); } code += "];\n"; code += " "; // initialize array for (size_t i = 0; i < array_only_lengths.size(); ++i) { auto idx = "idx" + NumToString(i); code += "for (int " + idx + " = 0; " + idx + " < " + NumToString(array_only_lengths[i].length) + "; ++" + idx + ") {"; } for (size_t i = 0; i < array_only_lengths.size(); ++i) { auto idx = "idx" + NumToString(i); if (i == 0) { code += name + "[" + idx; } else { code += "][" + idx; } } code += "] = _o"; for (size_t i = 0, j = 0; i < array_lengths.size(); ++i) { code += "." + namer_.Method("get", array_lengths[i].name) + "()"; if (array_lengths[i].length <= 0) continue; code += "[idx" + NumToString(j++) + "]"; } code += ";"; for (size_t i = 0; i < array_only_lengths.size(); ++i) { code += "}"; } } else { code += " " + name + " = "; code += SourceCast(field_type); code += "_o"; for (size_t i = 0; i < array_lengths.size(); ++i) { code += "." + namer_.Method("get", array_lengths[i].name) + "()"; } code += ";"; } code += "\n"; } array_lengths.pop_back(); } } void GenStructPackCall_ObjectAPI(const StructDef &struct_def, std::string &code, std::string prefix) const { for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { auto &field = **it; const auto &field_type = field.value.type; if (field_type.struct_def != nullptr) { GenStructPackCall_ObjectAPI(*field_type.struct_def, code, prefix + namer_.Field(field) + "_"); } else { code += ",\n"; code += prefix + namer_.Field(field); } } } std::string ConvertPrimitiveTypeToObjectWrapper_ObjectAPI( const std::string &type_name) const { if (type_name == "boolean") return "Boolean"; else if (type_name == "byte") return "Byte"; else if (type_name == "char") return "Character"; else if (type_name == "short") return "Short"; else if (type_name == "int") return "Integer"; else if (type_name == "long") return "Long"; else if (type_name == "float") return "Float"; else if (type_name == "double") return "Double"; return type_name; } std::string GenTypeGet_ObjectAPI(const flatbuffers::Type &type, bool vectorelem, bool wrap_in_namespace) const { auto type_name = GenTypeNameDest(type); // Replace to ObjectBaseAPI Type Name switch (type.base_type) { case BASE_TYPE_STRUCT: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_ARRAY: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_VECTOR: { if (type.struct_def != nullptr) { auto type_name_length = type.struct_def->name.length(); auto new_type_name = namer_.ObjectType(*type.struct_def); type_name.replace(type_name.length() - type_name_length, type_name_length, new_type_name); } else if (type.element == BASE_TYPE_UNION) { if (wrap_in_namespace) { type_name = namer_.NamespacedType(*type.enum_def) + "Union"; } else { type_name = namer_.Type(*type.enum_def) + "Union"; } } break; } case BASE_TYPE_UNION: { if (wrap_in_namespace) { type_name = namer_.NamespacedType(*type.enum_def) + "Union"; } else { type_name = namer_.Type(*type.enum_def) + "Union"; } break; } default: break; } if (vectorelem) { return type_name; } switch (type.base_type) { case BASE_TYPE_ARRAY: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_VECTOR: { type_name = type_name + "[]"; break; } default: break; } return type_name; } std::string GenConcreteTypeGet_ObjectAPI( const flatbuffers::Type &type) const { auto type_name = GenTypeNameDest(type); // Replace to ObjectBaseAPI Type Name switch (type.base_type) { case BASE_TYPE_STRUCT: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_ARRAY: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_VECTOR: { if (type.struct_def != nullptr) { auto type_name_length = type.struct_def->name.length(); auto new_type_name = namer_.ObjectType(*type.struct_def); type_name.replace(type_name.length() - type_name_length, type_name_length, new_type_name); } else if (type.element == BASE_TYPE_UNION) { type_name = namer_.NamespacedType(*type.enum_def) + "Union"; } break; } case BASE_TYPE_UNION: { type_name = namer_.NamespacedType(*type.enum_def) + "Union"; break; } default: break; } switch (type.base_type) { case BASE_TYPE_ARRAY: FLATBUFFERS_FALLTHROUGH(); // fall thru case BASE_TYPE_VECTOR: { type_name = type_name + "[]"; break; } default: break; } return type_name; } void GenStruct_ObjectAPI(const StructDef &struct_def, std::string &code) const { if (struct_def.generated) return; if (struct_def.attributes.Lookup("private")) { // For Java, we leave the enum unmarked to indicate package-private } else { code += "public "; } const auto class_name = namer_.ObjectType(struct_def); code += "class " + class_name; code += " {\n"; // Generate Properties for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { const auto &field = **it; if (field.deprecated) continue; if (field.value.type.base_type == BASE_TYPE_UTYPE) continue; if (field.value.type.element == BASE_TYPE_UTYPE) continue; auto type_name = GenTypeGet_ObjectAPI(field.value.type, false, true); if (field.IsScalarOptional()) type_name = ConvertPrimitiveTypeToObjectWrapper_ObjectAPI(type_name); const auto field_name = namer_.Field(field); code += " private " + type_name + " " + field_name + ";\n"; } // Generate Java getters and setters code += "\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { const auto &field = **it; if (field.deprecated) continue; if (field.value.type.base_type == BASE_TYPE_UTYPE) continue; if (field.value.type.element == BASE_TYPE_UTYPE) continue; const auto field_name = namer_.Field(field); const auto get_field = namer_.Method("get", field); auto type_name = GenTypeGet_ObjectAPI(field.value.type, false, true); if (field.IsScalarOptional()) type_name = ConvertPrimitiveTypeToObjectWrapper_ObjectAPI(type_name); code += " public " + type_name + " " + get_field + "() { return " + field_name + "; }\n\n"; std::string array_validation = ""; if (field.value.type.base_type == BASE_TYPE_ARRAY) { array_validation = "if (" + field_name + " != null && " + field_name + ".length == " + NumToString(field.value.type.fixed_length) + ") "; } code += " public void " + namer_.Method("set", field) + "(" + type_name + " " + field_name + ") { " + array_validation + "this." + field_name + " = " + field_name + "; }\n\n"; } // Generate Constructor code += "\n"; code += " public " + class_name + "() {\n"; for (auto it = struct_def.fields.vec.begin(); it != struct_def.fields.vec.end(); ++it) { const auto &field = **it; if (field.deprecated) continue; if (field.value.type.base_type == BASE_TYPE_UTYPE) continue; if (field.value.type.element == BASE_TYPE_UTYPE) continue; const auto get_field = namer_.Method("get", field); code += " this." + namer_.Field(field) + " = "; const auto type_name = GenTypeGet_ObjectAPI(field.value.type, false, true); if (IsScalar(field.value.type.base_type)) { if (field.IsScalarOptional()) { code += "null;\n"; } else { code += GenDefaultValue(field) + ";\n"; } } else { switch (field.value.type.base_type) { case BASE_TYPE_STRUCT: { if (IsStruct(field.value.type)) { code += "new " + type_name + "();\n"; } else { code += "null;\n"; } break; } case BASE_TYPE_ARRAY: { code += "new " + type_name.substr(0, type_name.length() - 1) + NumToString(field.value.type.fixed_length) + "];\n"; break; } default: { code += "null;\n"; break; } } } } code += " }\n"; if (parser_.root_struct_def_ == &struct_def) { const std::string struct_type = namer_.Type(struct_def); code += " public static " + class_name + " deserializeFromBinary(byte[] fbBuffer) {\n"; code += " return " + struct_type + "." + namer_.LegacyJavaMethod2("getRootAs", struct_def, "") + "(ByteBuffer.wrap(fbBuffer)).unpack();\n"; code += " }\n"; code += " public byte[] serializeToBinary() {\n"; code += " FlatBufferBuilder fbb = new FlatBufferBuilder();\n"; code += " " + struct_type + "." + namer_.LegacyJavaMethod2("finish", struct_def, "Buffer") + "(fbb, " + struct_type + ".pack(fbb, this));\n"; code += " return fbb.sizedByteArray();\n"; code += " }\n"; } code += "}\n\n"; } // This tracks the current namespace used to determine if a type need to be // prefixed by its namespace const Namespace *cur_name_space_; const IdlNamer namer_; }; } // namespace java bool GenerateJava(const Parser &parser, const std::string &path, const std::string &file_name) { java::JavaGenerator generator(parser, path, file_name); return generator.generate(); } } // namespace flatbuffers