Maven

Add the gRPC Dependencies:

<dependency>
  <groupId>io.grpc</groupId>
  <artifactId>grpc-netty</artifactId>
  <version>1.9.0</version>
</dependency>
<dependency>
  <groupId>io.grpc</groupId>
  <artifactId>grpc-protobuf</artifactId>
  <version>1.9.0</version>
</dependency>
<dependency>
  <groupId>io.grpc</groupId>
  <artifactId>grpc-stub</artifactId>
  <version>1.9.0</version>
</dependency>

If you need to generate service stubs from a gRPC Proto definition, you can add the generator plugin:

<build>
  <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:3.5.1-1:exe:${os.detected.classifier}</protocArtifact>
        <pluginId>grpc-java</pluginId>
        <pluginArtifact>io.grpc:protoc-gen-grpc-java:1.9.0:exe:${os.detected.classifier}</pluginArtifact>
      </configuration>
      <executions>
        <execution>
          <goals>
            <goal>compile</goal>
            <goal>compile-custom</goal>
          </goals>
        </execution>
      </executions>
    </plugin>
  </plugins>
</build>

Gradle

Add the gRPC Dependencies:

compile 'io.grpc:grpc-netty:1.9.0'
compile 'io.grpc:grpc-protobuf:1.9.0'
compile 'io.grpc:grpc-stub:1.9.0'

If you need to generate service stubs from a gRPC Proto definition, you can add the generator plugin:

apply plugin: 'java'
apply plugin: 'com.google.protobuf'

buildscript {
  repositories {
    mavenCentral()
  }
  dependencies {
    // ASSUMES GRADLE 2.12 OR HIGHER. Use plugin version 0.7.5 with earlier
    // gradle versions
    classpath 'com.google.protobuf:protobuf-gradle-plugin:0.8.3'
  }
}

protobuf {
  protoc {
    artifact = "com.google.protobuf:protoc:3.5.1-1"
  }
  plugins {
    grpc {
      artifact = 'io.grpc:protoc-gen-grpc-java:1.9.0'
    }
  }
  generateProtoTasks {
    all()*.plugins {
      grpc {}
    }
  }
}