Introduction and examples of Google ProtocolBuffer (PB), protocolbufferpb

Introduction and examples of Google ProtocolBuffer (PB), protocolbufferpb
Introduction

• ProtocolBuffer (PB) is a lightweight and efficient storage format for structured data serialization.
• Similar to xml and json, PB is more efficient and space-saving than the former two, and saves user traffic in mobile development.
• How can PB reduce traffic? From its encoding method, PB adopts the Zigzag encoding and makes full use of the Varint technology to save space in the level-2 system.

Instance

• Step 1: Write the. proto file. Go to the official google instance and store it as addressbook. proto

package tutorial;option java_package = "com.example.tutorial";option java_outer_classname = "AddressBookProtos";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;}message AddressBook {  repeated Person person = 1;}

• Step 2: Compile the. proto file, use the PB-related compilation tool protoc, and generate a java class

protoc -I=$SRC_DIR --cpp_out=$DST_DIR $SRC_DIR/addressbook.proto

protoc -I=. --java_out=. addressbook.proto

• Step 3: Apply the generated classes and perform serialization and deserialization operations, depending on the library protobuf-java-2.6.1.jar (and the version must be consistent with the previous protoc Version)

// Generate the object Person john = Person. newBuilder (). setId (1234 ). setName ("John Doe "). setEmail ("jdoe@example.com "). addPhone (Person. phoneNumber. newBuilder (). setNumber ("555-4321 "). setType (Person. phoneType. HOME )). build (); System. out. println (john. toString (); // serialized as a binary array byte [] johnbyte = john. toByteArray (); // deserialization (the intermediate process can be considered as a network transfer, file storage, etc.) // compare the two systems. out output try {Person john2 = Person. parseFrom (johnbyte); System. out. println (john2.toString ();} catch (InvalidProtocolBufferException e) {// TODO Auto-generated catch block e. printStackTrace ();}

Extension

• Write. proto details
• PB Encoding Algorithm
• Notes for PB-based protocol upgrade

Download

• The following addresses provide complete download of the above instance project, resources include: protobuf-2.6.1.zip source code; protoc-2.6.1-win32; protobuf-java-2.6.1.jar; A serialized deserialization instance
• Download Portal

Reference

• Http://www.ibm.com/developerworks/cn/linux/l-cn-gpb/#ibm-pcon
• Http://www.cnblogs.com/shrimps/archive/2008/11/06/1327988.html
• Http://stackoverflow.com/questions/14028293/google-protocol-buffers-vs-json-vs-xml
• Https://github.com/google/protobuf
• Https://developers.google.com/protocol-buffers/docs/downloads
• Https://developers.google.com/protocol-buffers/docs/javatutorial
• Http://repo2.maven.org/maven2/com/google/protobuf/protobuf-java/2.6.1/