最近google发布了grpc1.0，数据交互使用了protocol buffer，相比之前使用的hession和json序列化方式性能应该提升不少，所有先搞一个grpc的hello world跑一下，项目使用maven搭建，并使用Eclipse开发。
一.使用Eclipse创建maven项目，添加pom配置
1.添加grpc1.0 maven依赖
UTF-8 1.4.0 io.grpc grpc-netty ${grpc.version} io.grpc grpc-protobuf ${grpc.version} io.grpc grpc-stub ${grpc.version} io.grpc grpc-testing ${grpc.version} test junit junit 4.11 test org.mockito mockito-core 1.9.5 test
2.配置protobuf maven插件
配置了protobuf 插件后，可以自动将.proto文件生成对应的java代码。
kr.motd.maven os-maven-plugin 1.4.1.Final org.xolstice.maven.plugins protobuf-maven-plugin 0.5.0 com.google.protobuf:protoc:3.3.0:exe:${os.detected.classifier} grpc-java io.grpc:protoc-gen-grpc-java:${grpc.version}:exe:${os.detected.classifier} compile compile-custom
配置完，整个pom.xml文件内容如下：
4.0.0 com.bijian test-grpc 0.0.1-SNAPSHOT jar test-grpc http://maven.apache.org UTF-8 1.4.0 io.grpc grpc-netty ${grpc.version} io.grpc grpc-protobuf ${grpc.version} io.grpc grpc-stub ${grpc.version} io.grpc grpc-testing ${grpc.version} test junit junit 4.11 test org.mockito mockito-core 1.9.5 test kr.motd.maven os-maven-plugin 1.4.1.Final org.xolstice.maven.plugins protobuf-maven-plugin 0.5.0 com.google.protobuf:protoc:3.3.0:exe:${os.detected.classifier} grpc-java io.grpc:protoc-gen-grpc-java:${grpc.version}:exe:${os.detected.classifier} compile compile-custom
二.编写proto文件helloworld.proto
syntax = "proto3";
option java_multiple_files = true;
option java_package = "io.grpc.examples.helloworld";
option java_outer_classname = "HelloWorldProto";
option objc_class_prefix = "HLW";
package helloworld;
// The greeting service definition.
service Greeter {
// Sends a greeting
rpc 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;
}
然后点击pom.xml右击->Run as->Maven install，将会在target/generatedo-sources下生成的对应的java代码，如下所示：
将生成的代码拷贝到src/main/java下，如下所示（有几处@java.lang.Override的编译错误，去掉即可）：
三.编写grpc 服务端HelloWorldServer.java
package com.bijian.test_grpc;
import io.grpc.Server;
import io.grpc.ServerBuilder;
import io.grpc.examples.helloworld.GreeterGrpc;
import io.grpc.examples.helloworld.HelloReply;
import io.grpc.examples.helloworld.HelloRequest;
import io.grpc.stub.StreamObserver;
import java.io.IOException;
public class HelloWorldServer {
private int port = 50051;
private Server server;
private void start() throws IOException {
server = ServerBuilder.forPort(port)
.addService(new GreeterImpl())
.build()
.start();
System.out.println("service start...");
Runtime.getRuntime().addShutdownHook(new Thread() {
@Override
public void run() {
System.err.println("*** shutting down gRPC server since JVM is shutting down");
HelloWorldServer.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();
}
}
public static void main(String[] args) throws IOException, InterruptedException {
final HelloWorldServer server = new HelloWorldServer();
server.start();
server.blockUntilShutdown();
}
// 实现 定义一个实现服务接口的类
private class GreeterImpl extends GreeterGrpc.GreeterImplBase {
public void sayHello(HelloRequest req, StreamObserver responseObserver) {
System.out.println("service:"+req.getName());
HelloReply reply = HelloReply.newBuilder().setMessage(("Hello: " + req.getName())).build();
responseObserver.onNext(reply);
responseObserver.onCompleted();
}
}
}
四.编写grpc 客户端 HelloWorldClient.java
package com.bijian.test_grpc;
import io.grpc.ManagedChannel;
import io.grpc.ManagedChannelBuilder;
import io.grpc.examples.helloworld.GreeterGrpc;
import io.grpc.examples.helloworld.HelloReply;
import io.grpc.examples.helloworld.HelloRequest;
import java.util.concurrent.TimeUnit;
public class HelloWorldClient {
private final ManagedChannel channel;
private final GreeterGrpc.GreeterBlockingStub blockingStub;
public HelloWorldClient(String host,int port){
channel = ManagedChannelBuilder.forAddress(host,port)
.usePlaintext(true)
.build();
blockingStub = GreeterGrpc.newBlockingStub(channel);
}
public void shutdown() throws InterruptedException {
channel.shutdown().awaitTermination(5, TimeUnit.SECONDS);
}
public void greet(String name){
HelloRequest request = HelloRequest.newBuilder().setName(name).build();
HelloReply response = blockingStub.sayHello(request);
System.out.println(response.getMessage());
}
public static void main(String[] args) throws InterruptedException {
HelloWorldClient client = new HelloWorldClient("127.0.0.1",50051);
for(int i=0;i<5;i++){
client.greet("world:"+i);
}
}
}
五.项目完整结构
六.项目运行结果
服务端
service start... service:world:0 service:world:1 service:world:2 service:world:3 service:world:4 三月 17, 2018 9:30:40 下午 io.grpc.netty.NettyServerTransport notifyTerminated
客户端
Hello: world:0 Hello: world:1 Hello: world:2 Hello: world:3 Hello: world:4
参考文章：http://blog.csdn.net/whzhaochao/article/details/52421867
