一、Maven的下载安装与配置

1.下载网址 http://maven.apache.org/download.cgi

选择下载二进制压缩归档文件 解压到任意目录下

2.配置环境变量

在系统变量新建两个变量M2_HOME和MAVEN_HOME，值为安装路径

编辑系统变量PATH，添加%M2_HOME%\bin

3.验证
命令行 mvn -v

4.配置settings.xml

增加本地仓库

在被注释掉的localRepository位置下一行 增加

<localRepository>自定义本地仓库路径（例：D:\software\gogogo）</localRepository>

配置阿里镜像仓库 在被注释掉的mirror下增加

<mirrors>
    <!-- mirror
     | Specifies a repository mirror site to use instead of a given repository. The repository that
     | this mirror serves has an ID that matches the mirrorOf element of this mirror. IDs are used
     | for inheritance and direct lookup purposes, and must be unique across the set of mirrors.
     |
    <mirror>
      <id>mirrorId</id>
      <mirrorOf>repositoryId</mirrorOf>
      <name>Human Readable Name for this Mirror.</name>
      <url>http://my.repository.com/repo/path</url>
    </mirror>
     -->
     <mirror>
        <id>aliyun-public</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun public</name>
        <url>https://maven.aliyun.com/repository/public</url>
    </mirror>

    <mirror>
        <id>aliyun-central</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun central</name>
        <url>https://maven.aliyun.com/repository/central</url>
    </mirror>

    <mirror>
        <id>aliyun-spring</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun spring</name>
        <url>https://maven.aliyun.com/repository/spring</url>
    </mirror>

    <mirror>
        <id>aliyun-spring-plugin</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun spring-plugin</name>
        <url>https://maven.aliyun.com/repository/spring-plugin</url>
    </mirror>

    <mirror>
        <id>aliyun-apache-snapshots</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun apache-snapshots</name>
        <url>https://maven.aliyun.com/repository/apache-snapshots</url>
    </mirror>

    <mirror>
        <id>aliyun-google</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun google</name>
        <url>https://maven.aliyun.com/repository/google</url>
    </mirror>

    <mirror>
        <id>aliyun-gradle-plugin</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun gradle-plugin</name>
        <url>https://maven.aliyun.com/repository/gradle-plugin</url>
    </mirror>

    <mirror>
        <id>aliyun-jcenter</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun jcenter</name>
        <url>https://maven.aliyun.com/repository/jcenter</url>
    </mirror>

    <mirror>
        <id>aliyun-releases</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun releases</name>
        <url>https://maven.aliyun.com/repository/releases</url>
    </mirror>

    <mirror>
        <id>aliyun-snapshots</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun snapshots</name>
        <url>https://maven.aliyun.com/repository/snapshots</url>
    </mirror>

    <mirror>
        <id>aliyun-grails-core</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun grails-core</name>
        <url>https://maven.aliyun.com/repository/grails-core</url>
    </mirror>

    <mirror>
        <id>aliyun-mapr-public</id>
        <mirrorOf>*</mirrorOf>
        <name>aliyun mapr-public</name>
        <url>https://maven.aliyun.com/repository/mapr-public</url>
    </mirror>
  </mirrors>

二、配置IDEA

在File-Settings-Build,Execution,Development-Maven下

Maven home path :Maven解压路径

User Setting file：打开到刚刚修改的settings.xml文件

Local repository：本地仓库地址 修改完上一步后 这一条一般会默认出现

三、创建Maven项目工程

File-New-Project

配置pom.xml文件，导入gRPC的依赖和插件

<?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>com.wly</groupId>
    <artifactId>HelloWorld-gRPC-java</artifactId>

    <version>1.0-SNAPSHOT</version>

    <dependencies>
    <dependency>
        <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java</artifactId>
            <version>3.8.0</version>
        </dependency>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-all</artifactId>
            <version>1.14.0</version>
        </dependency>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-netty-shaded</artifactId>
            <version>1.14.0</version>
        </dependency>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-protobuf</artifactId>
            <version>1.14.0</version>
        </dependency>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-stub</artifactId>
            <version>1.26.0</version>
        </dependency>

    </dependencies>

    <build>
        <defaultGoal>compile</defaultGoal>
        <extensions>
            <extension>
                <groupId>kr.motd.maven</groupId>
                <artifactId>os-maven-plugin</artifactId>
                <version>1.5.0.Final</version>
            </extension>
        </extensions>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.6.1</version>
                    <configuration>
                        <source>1.6</source>
                        <target>1.6</target>
                    </configuration>
                </plugin>
            <plugin>
                <groupId>org.xolstice.maven.plugins</groupId>
                <artifactId>protobuf-maven-plugin</artifactId>
                <version>0.5.1</version>

               
                <configuration>
                    <mainClass>com.wly.gRpc_helloworld.HelloWorld_Client.main</mainClass>
                    <protocArtifact>com.google.protobuf:protoc:3.5.1-1:exe:${os.detected.classifier}</protocArtifact>
                    <pluginId>grpc-java</pluginId>
                    <pluginArtifact>io.grpc:protoc-gen-grpc-java:1.36.0:exe:${os.detected.classifier}</pluginArtifact>
                </configuration>
                <executions>
                    <execution>
                        <goals>

                            <goal>compile-custom</goal>
                            <goal>compile</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

引入.proto文件

在main文件夹下，新建proto文件夹 在建好的proto文件夹下创建 helloworld.proto文件 增加内容

// Copyright 2015 gRPC authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

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;
}

右击Maven.Projects\protobuf\protobuf:compile ，选择run，生成用于序列化的java文件。
再右击Maven.Projects\protobuf\protobuf:compile-custom，选择run，生成用于rpc的java代码。

可能出现的问题

解决方法：

Alt+Enter:选择Add Javaee 6 JARs to Module dependencies，下载相应的包

编写客户端和服务端代码

服务端代码：HelloWorld_Server.java

package com.wly.gRpc_helloworld;

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;
import java.util.logging.Logger;


public class HelloWorld_Server {
    private static final Logger logger = Logger.getLogger(HelloWorld_Server.class.getName());


    private int port = 50051;
    private Server server;

    private void start() throws IOException{
        server = ServerBuilder.forPort(port)
                .addService(new GreeterImpl())
                .build()
                .start();
        logger.info("Server started, listening on "+ port);

        Runtime.getRuntime().addShutdownHook(new Thread(){

            @Override
            public void run(){

                System.err.println("*** shutting down gRPC server since JVM is shutting down");
                HelloWorld_Server.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 HelloWorld_Server server = new HelloWorld_Server();
        server.start();
        server.blockUntilShutdown();
    }


    // 实现 定义一个实现服务接口的类
    private class GreeterImpl extends GreeterGrpc.GreeterImplBase {

        @Override
        public void sayHello(HelloRequest req,StreamObserver<HelloReply> responseObserver){
           // HelloReply reply = HelloReply.newBuilder().setMessage(("{\"order\":\"1000\",\"operator\":\"China\",\"function\":\"start\"} "+req.getName())).build();
            HelloReply reply = HelloReply.newBuilder().setMessage(("Hello "+req.getName())).build();
            responseObserver.onNext(reply);
            responseObserver.onCompleted();
            System.out.println("Message from gRPC-Client:" + req.getName());
        }
    }
}

客户端代码： HelloWorld_Client.java

package com.wly.gRpc_helloworld;

import io.grpc.ManagedChannel;
import io.grpc.ManagedChannelBuilder;
import io.grpc.StatusRuntimeException;
import io.grpc.examples.helloworld.GreeterGrpc;
import io.grpc.examples.helloworld.HelloReply;
import io.grpc.examples.helloworld.HelloRequest;

import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;


public class HelloWorld_Client {
    private final ManagedChannel channel;
    private final GreeterGrpc.GreeterBlockingStub blockingStub;
    private static final Logger logger = Logger.getLogger(HelloWorld_Client.class.getName());

    public HelloWorld_Client(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;
        try{
            response = blockingStub.sayHello(request);
        } catch (StatusRuntimeException e)
        {
            logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
            return;
        }
        logger.info("Message from gRPC-Server: "+response.getMessage());
    }

    public static void main(String[] args) throws InterruptedException {
       // HelloWorld_Client client = new HelloWorld_Client("192.168.2.122",9002);
       HelloWorld_Client client = new HelloWorld_Client("127.0.0.1",50051);
 
        try{
            String user = "world";
            if (args.length > 0){
                user = args[0];
            }
            client.greet(user);
        }finally {
            client.shutdown();
        }
    }
}

运行

先运行HelloWorld_Server.java，再运行HelloWorld_Client.java

得到下图所示结果 证明通信成功