Comparison of Protobuf and Interface

1. Data type

1.1. Basic types

[Note] In Java, unsigned 32-bit and 64-bit integers are represented using their signed logarithms, with the top bit only stored in the sign bit.

2. Composite types

2.1. Enumeration

• Original pb code

enum TrafficLightColor {
    TRAFFIC_LIGHT_COLOR_INVALID = 0;
    TRAFFIC_LIGHT_COLOR_UNSET = 1;
    TRAFFIC_LIGHT_COLOR_GREEN = 2;
    TRAFFIC_LIGHT_COLOR_YELLOW = 3;
    TRAFFIC_LIGHT_COLOR_RED = 4;
}

• Generated java code

Enumerations are constants, so use uppercase

2.2. Arrays

• Original pb code

message VipIDToRidReq {
    repeated uint32 vipID = 1;
}

• Generated java code

The bottom layer is actually an ArrayList

2.3. Collections

PB does not support unordered and non-repeating collections, and can only borrow arrays to implement, and needs to remove duplicates by itself.

2.4. Dictionaries

• Original pb code

message BatchOnlineRes {
    map<uint32, uint32> onlineMap = 1;//online status
}

• Generated java code

2.5. Nesting

• Original pb code

message BatchAnchorInfoRes {
    map<uint32, AnchorInfo> list = 1; //user information map list
}
/*
* The function of the corresponding interface: get user information in batches or individually
*/
message AnchorInfo {
    uint32 ownerUid = 1 [json_name="uid"]; //user id
    string nickName = 2 [json_name="nn"]; //User nickname
    string smallAvatar = 3 [json_name="savt"]; //full path of user avatar - small
    string middleAvatar = 4 [json_name="mavt"]; //Full path of user avatar - middle
    string bigAvatar = 5 [json_name="bavt"]; //Full path of user avatar - big
    string avatar = 6 [json_name="avt"]; //User avatar
}

• Generated java code

3. Field default value

• For strings, the default is the empty string.
• For bytes, the default is the null byte.
• For bools, the default is false.
• For numeric types, the default value is zero.
• For enums, the default is the first defined enum value, which must be 0.
• For the message field, the field is not set. Its exact value is language dependent. See the generated code guide for details.

4. Overall structure

5. Community profile

• Community homepage address: https://developers.google.cn/protocol-buffers/
• Community open source address: https://github.com/google/protobuf
• Maven of related jars: https://search.maven.org/search?q=com.google.protobuf