Shulou(Shulou.com)06/03 Report--

Welcome to protocol buffers's developer Guide. Protocol buffers is a language-neutral, platform-neutral extension to serialize structured data in communication protocols, data storage, and other areas.

This document is aimed at developers of Java,C++ or Python who want to use Protocol Buffers in the applications they develop. This introduction to the summary of Protocol Buffers will show you how to start using Protocol Buffers. If you want to learn more about Protocol Buffers, you can go to the tutorials or protocol buffer encoding page to learn more.

For reference documentation on API, please refer to the page: reference documentation provides references for all three languages, as well as guidelines for .proto language and style.

What is Protocol Buffers?

Protocol buffers is a flexible, efficient, automated tool for serializing structured data-you can think of Protocol buffers as XML, but it's smaller, faster and easier.

You can define your structured data yourself, and then you can use specific code generation tools to easily read and write your structured data. The reading and writing of these data can be a series of data streams and use different computer programming languages. You can even update your data structure without destroying the already deployed programs.

How does Protocol Buffers work?

You need to figure out how you want your data to be serialized. You define the structured data of your messages through proto files.

Each protocol buffer message is a small information recording logic, this message contains a series of names, variable comparison sequence. Here are some basic .proto files that define a message that contains an person message:

Message Person {required string name = 1; required int32 id = 2; optional string email = 3; enum PhoneType {MOBILE = 0; HOME = 1; WORK = 2;} message PhoneNumber {required string number = 1; optional PhoneType type = 2 [default = HOME];} repeated PhoneNumber phone = 4;}

You can see from the above that the format of this message is very simple-each message type has one or more unique numbered fields, and each field contains a name and variable type.

Variables can be numeric (× × × or floating point) (numbers), Boolean (booleans), string (strings), native binary (raw bytes) or even other protocol buffer message types, allowing you to structure your data hierarchically.

You can specify fields as optional fields (optional fields), must fields (required fields) and duplicate fields (repeated fields). You can find more definitions of .proto in the Protocol Buffer Language Guide page below.

Once you have successfully defined your message, you can use your defined .proto to run the protocol buffer compiler (protocol buffer compiler) to generate data access classes for the language you are using.

For each field, simple access methods (such as name () and set_name ()) and methods to serialize to and deserialize native binary data are provided in the data access class.

For the above definition, if you are using the C++ language now, when you compile the message definition, you will get a class called Person. You can use this class to populate data in your application, serialize the data, and retrieve Person data from the serialized data (protocol buffer messages).

Then you can write some code similar to Person person;.

Person person;person.set_name ("John Doe"); person.set_id (1234); person.set_email ("jdoe@example.com"); fstream output ("myfile", ios::out | ios::binary); person.SerializeToOstream (& output)

You can then read the message:

Fstream input ("myfile", ios::in | ios::binary); Person person;person.ParseFromIstream (& input); cout

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.