pom.xml

protobuf-maven-plugin里protobuf.version和grpc.version可从maven获取最新版本

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>grpc_demo</artifactId>
    <version>1.0-SNAPSHOT</version>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <os.detected.classifier>windows-x86_64</os.detected.classifier>
        <grpc.version>1.60.1</grpc.version>
        <protobuf.version>3.25.1</protobuf.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-netty-shaded</artifactId>
            <version>${grpc.version}</version>
        </dependency>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-protobuf</artifactId>
            <version>${grpc.version}</version>
        </dependency>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-stub</artifactId>
            <version>${grpc.version}</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.xolstice.maven.plugins</groupId>
                <artifactId>protobuf-maven-plugin</artifactId>
                <version>0.6.1</version>
                <configuration>
                    <protocArtifact>com.google.protobuf:protoc:${protobuf.version}:exe:${os.detected.classifier}
                    </protocArtifact>
                    <pluginId>grpc-java</pluginId>
                    <pluginArtifact>io.grpc:protoc-gen-grpc-java:${grpc.version}:exe:${os.detected.classifier}
                    </pluginArtifact>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>compile-custom</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

步骤

目录结构

src/main/proto目录编写user.proto文件

syntax = "proto3";
message UserRequest {
  string name = 1;
  string age = 2;
}
message UserResponse {
  string birthday = 1;
  string city = 2;
}
service UserService {
  rpc searchBirthdayAndCity(UserRequest) returns (UserResponse);
}

点击maven工具protobuf:compile和protobuf:compile-custom, 编译生成java文件
经过步骤2之后, 会在target目录下生成两个java文件, 将这两个文件拷贝到工程目录中
编写server和client的代码, 分别启动server和client的main()方法

server

public static void main(String[] args) throws Exception {
        io.grpc.Server server = ServerBuilder.forPort(8088)
                .addService(new UserServiceGrpc.UserServiceImplBase() {
                    @Override
                    public void searchBirthdayAndCity(User.UserRequest request, StreamObserver<User.UserResponse> responseObserver) {
                        System.out.printf("receive search request ===  name:%s,age:%s\n", request.getName(), request.getAge());
                        User.UserResponse response = User.UserResponse.newBuilder()
                                .setBirthday(LocalDate.now().toString())
                                .setCity("beijing").build();
                        responseObserver.onNext(response);
                        responseObserver.onCompleted();
                    }
                }).build();
        server.start();
        server.awaitTermination();
}

client

 public static void main(String[] args) {
        ManagedChannel channel = ManagedChannelBuilder.forAddress("localhost", 8088)
                .usePlaintext()
                .build();

        UserServiceGrpc.UserServiceBlockingStub stub = UserServiceGrpc.newBlockingStub(channel);
        User.UserRequest request = User.UserRequest.newBuilder()
                .setName("jay chou")
                .setAge("30")
                .build();

        User.UserResponse response = stub.searchBirthdayAndCity(request);
        System.out.println(response);
        channel.shutdown();
}