| // Protocol Buffers - Google's data interchange format |
| // Copyright 2007 Google Inc. All rights reserved. |
| // https://developers.google.com/protocol-buffers/ |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following disclaimer |
| // in the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| // Author: kenton@google.com (Kenton Varda) |
| // |
| // This is proto2's version of MessageSet. See go/messageset to learn what |
| // MessageSets are and how they are used. |
| // |
| // In proto2, we implement MessageSet in terms of extensions, except with a |
| // special wire format for backwards-compatibility. To define a message that |
| // goes in a MessageSet in proto2, you must declare within that message's |
| // scope an extension of MessageSet named "message_set_extension" and with |
| // the field number matching the type ID. So, for example, this proto1 code: |
| // message Foo { |
| // enum TypeId { MESSAGE_TYPE_ID = 1234; } |
| // } |
| // becomes this proto2 code: |
| // message Foo { |
| // extend google.protobuf.bridge.MessageSet { |
| // optional Foo message_set_extension = 1234; |
| // } |
| // } |
| // |
| // Now you can use the usual proto2 extensions accessors to access this |
| // message. For example, the proto1 code: |
| // MessageSet mset; |
| // Foo* foo = mset.get_mutable<Foo>(); |
| // becomes this proto2 code: |
| // google::protobuf::bridge::MessageSet mset; |
| // Foo* foo = mset.MutableExtension(Foo::message_set_extension); |
| // |
| // Of course, new code that doesn't have backwards-compatibility requirements |
| // should just use extensions themselves and not worry about MessageSet. |
| |
| syntax = "proto2"; |
| |
| package google.protobuf.bridge; |
| |
| option java_outer_classname = "MessageSetProtos"; |
| option java_multiple_files = true; |
| option cc_enable_arenas = true; |
| option objc_class_prefix = "GPB"; |
| |
| // This is proto2's version of MessageSet. |
| message MessageSet { |
| option message_set_wire_format = true; |
| |
| extensions 4 to max; |
| } |
