How to define value and id for enum in protobuf? (

问题:

I am new to protobuf usage.

i am planning to write protobuf def with enum(s) in it.

is there any way to provide id, value and as well description in it.

after compilation i want generated enum should be equivalent as below example

enum Sample{
  W(0, "W"), P(0, "P"), C(0, "C"), B(0, "B")
  private final int id;
  private final String value;

  private Status(int id, String value) {
    this.id= id;
    this.value = value;
  }
}

Any help is very appreciated.

回答1:

There is no way to generate exactly the Java enum in your example, but you can use "custom options" to add arbitrary annotation to protobuf declarations. See the documentation (scroll down a little bit to "custom options").

import "google/protobuf/descriptor.proto";

extend google.protobuf.EnumValueOptions {
  optional string name = 51234;
}

enum MyEnum {
  FOO = 0 [(name) = "foo"];
  BAR = 1 [(name) = "bar"];
}

The annotation is accessed through the EnumValueDescriptor interface.