gradle依赖库：

implementation 'com.google.protobuf:protobuf-java:3.4.0'

implementation 'com.google.protobuf:protobuf-java-util:3.4.0'

0.编写.proto文件，编译生成对应Java源文件：

syntax = "proto2";

option java_generic_services = true;

option java_package = "gj.protobuf.sample";

option java_outer_classname = "ProtoSample";

message Student {

required int32 id = 1;

optional string name = 2;

}

protoc --java_out=..\..\java ProtobufSample.proto

1.编写Java文件：

package gj.protobuf.sample;

import com.google.protobuf.InvalidProtocolBufferException;

/**

* Author: areful

*/

public class ProtoSampleTest {

public static void main(String[] args) {

ProtoSample.Student student = ProtoSample.Student.newBuilder()

.setId(1)

.setName("areful")

.build();

System.out.println(student);

byte[] data = student.toByteArray();

try {

ProtoSample.Student student1 = ProtoSample.Student.parseFrom(data);

System.out.println(student1);

} catch (InvalidProtocolBufferException e) {

e.printStackTrace();

}

}

}

2.编译运行：