Rpc框架：grpc-java客户端与服务端

1.添加maven依赖

    <dependency><groupId>io.grpc</groupId><artifactId>grpc-netty</artifactId><version>1.6.1</version></dependency><dependency><groupId>io.grpc</groupId><artifactId>grpc-protobuf</artifactId><version>1.6.1</version></dependency><dependency><groupId>io.grpc</groupId><artifactId>grpc-stub</artifactId><version>1.6.1</version></dependency>

    <extensions><extension><groupId>kr.motd.maven</groupId><artifactId>os-maven-plugin</artifactId><version>1.5.0.Final</version></extension></extensions><plugins><plugin><groupId>org.xolstice.maven.plugins</groupId><artifactId>protobuf-maven-plugin</artifactId><version>0.5.0</version><configuration><protocArtifact>com.google.protobuf:protoc:3.3.0:exe:${os.detected.classifier}</protocArtifact><pluginId>grpc-java</pluginId><pluginArtifact>io.grpc:protoc-gen-grpc-java:1.6.1:exe:${os.detected.classifier}</pluginArtifact></configuration><executions><execution><goals><goal>compile</goal><goal>compile-custom</goal></goals></execution></executions></plugin></plugins>

2.编写proto文件(HelloWorld.proto)，并定义一个接口

syntax = "proto3";option java_package = "com";package helloworld;// The greeter service definition.
service Greeter {// Sends a greetingrpc SayHello (HelloRequest) returns (HelloReply) {}
}// The request message containing the user's name.
message HelloRequest {string name = 1;
}// The response message containing the greetings
message HelloReply {string message = 1;
}

3.编译打包

a:执行mvn package 打包

打包如图所示:

b:将  grpc-my-1.0-SNAPSHOT.jar，添加到maven本地厂库

如：

mvn install:install-file -DgroupId=com.my.grpc -DartifactId=hwb -Dversion=1.0-SNAPSHOT -Dpackaging=jar -Dfile=target/grpc-my-1.0-SNAPSHOT.jar

c:并在项目中添加此jar包：

    <dependency><groupId>com.my.grpc</groupId><artifactId>hwb</artifactId><version>1.0-SNAPSHOT</version></dependency>

4.继承 GreeterGrpc.GreeterImplBase并实现

   创建java类，类名为 HelloServiceGrpc；

import com.GreeterGrpc;
import com.HelloWorld;
import io.grpc.stub.StreamObserver;public class HelloServiceGrpc extends GreeterGrpc.GreeterImplBase {@Overridepublic void sayHello(HelloWorld.HelloRequest request, StreamObserver<HelloWorld.HelloReply> responseObserver) {String name = request.getName();System.out.println("您的名字:" + name);HelloWorld.HelloReply.Builder builder = HelloWorld.HelloReply.newBuilder();builder.setMessage("小伙子不错的、");responseObserver.onNext(builder.build());responseObserver.onCompleted();}
}

5.server服务端（HelloServer）

import io.grpc.Server;
import io.grpc.ServerBuilder;import java.io.IOException;
public class HelloServer {private Server server;public static void main(String[] args) throws IOException, InterruptedException {final HelloServer server = new HelloServer();server.start();server.blockUntilShutdown();}private void start() throws IOException {    /* The port on which the server should run */int port = 50051;//这个部分启动serverserver = ServerBuilder.forPort(port).addService(new HelloServiceGrpc()).build().start();System.out.println("Server started, listening on "+ port);Runtime.getRuntime().addShutdownHook(new Thread(){@Overridepublic void run(){System.err.println("*** shutting down gRPC server since JVM is shutting down");HelloServer.this.stop();System.err.println("*** server shut down");}});}private void stop(){if (server != null){server.shutdown();}}// block 一直到退出程序private void blockUntilShutdown() throws InterruptedException {if (server != null){server.awaitTermination();}}}

6.client客户端

import com.GreeterGrpc;
import com.HelloWorld;
import io.grpc.ManagedChannel;
import io.grpc.ManagedChannelBuilder;/*** Created by Hua wb on 2018/10/11.*/
public class HelloClient {public static void main(String[] args) {ManagedChannel localhost = ManagedChannelBuilder.forAddress("localhost", 50051).usePlaintext(true).build();GreeterGrpc.GreeterBlockingStub stub = GreeterGrpc.newBlockingStub(localhost);HelloWorld.HelloRequest hwb = HelloWorld.HelloRequest.newBuilder().setName("luck").build();HelloWorld.HelloReply helloReply = stub.sayHello(hwb);System.out.println(helloReply.getMessage());}
}