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@@ -26,7 +26,7 @@ Hello World method.
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- Create a Go client that accesses the same Java server.
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- Update the service with more advanced features like RPC streaming.
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-The complete code for the example is available in [wherever we put it]. You can
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+The complete code for the example is available in the `grpc-common` GitHub repository. You can
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work along with the example and hack on the code in the comfort of your own
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computer, giving you hands-on practice of really writing
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gRPC code. We use the Git versioning system for source code management:
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@@ -174,7 +174,7 @@ to generated code. As we're creating Java code, we use the gRPC Java plugin.
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To build the plugin:
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-```
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+```sh
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$ pushd external/grpc_java
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$ make java_plugin
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$ popd
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@@ -182,7 +182,7 @@ $ popd
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To use it to generate the code:
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-```
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+```sh
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$ mkdir -p src/main/java
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$ protoc -I . helloworld.proto
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--plugin=protoc-gen-grpc=external/grpc_java/bins/opt/java_plugin \
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@@ -194,27 +194,25 @@ This generates the following classes, which contain all the generated code we ne
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- [`Helloworld.java`](java/src/main/java/ex/grpc/Helloworld.java), which has all the protocol buffer code to populate, serialize, and retrieve our `HelloRequest` and `HelloReply` message types
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- [`GreetingsGrpc.java`](java/src/main/java/ex/grpc/GreetingsGrpc.java), which contains (along with some other useful code):
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- - an interface for `Greetings` servers to implement
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+ - an interface for `Greetings` servers to implement
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-```
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+ ```java
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public static interface Greetings {
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public void hello(ex.grpc.Helloworld.HelloRequest request,
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com.google.net.stubby.stub.StreamObserver<ex.grpc.Helloworld.HelloReply> responseObserver);
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}
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-```
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+ ```
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- - _stub_ classes that clients can use to talk to a `Greetings` server.
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+ - _stub_ classes that clients can use to talk to a `Greetings` server.
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-```
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+ ```java
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public static class GreetingsStub extends
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com.google.net.stubby.stub.AbstractStub<GreetingsStub, GreetingsServiceDescriptor>
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implements Greetings {
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...
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}
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-```
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-
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-_Does gRPC output multiple Java classes per proto by default?_
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+ ```
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<a name="server"></a>
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### Writing a server
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@@ -233,7 +231,7 @@ Our server application has two classes:
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implements the behaviour we require of our GreetingService. There are a
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number of important features of gRPC being used here:
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-```
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+```java
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public void hello(Helloworld.HelloRequest req,
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StreamObserver<Helloworld.HelloReply> responseObserver) {
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Helloworld.HelloReply reply = Helloworld.HelloReply.newBuilder().setMessage(
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@@ -262,7 +260,7 @@ number of important features of gRPC being used here:
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other main feature required to provde the gRPC service; how to allow a service
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implementation to be accessed from the network.
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-```
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+```java
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private void start() throws Exception {
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server = NettyServerBuilder.forPort(port)
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.addService(GreetingsGrpc.bindService(new GreetingsImpl()))
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@@ -302,7 +300,7 @@ transport handling; its constructor accepts the host name and port of the
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service. The channel in turn is used to construct the Stub.
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-```
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+```java
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private final ChannelImpl channel;
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private final GreetingGrpc.GreetingBlockingStub blockingStub;
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@@ -324,7 +322,7 @@ It:
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- prints out the greeting
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-```
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+```java
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public void greet(String name) {
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logger.debug("Will try to greet " + name + " ...");
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try {
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@@ -344,7 +342,7 @@ It:
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The main method puts together the example so that it can be run from a command
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line.
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-```
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+```java
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/* Access a service running on the local machine on port 50051 */
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HelloClient client = new HelloClient("localhost", 50051);
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String user = "world";
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@@ -379,13 +377,13 @@ $ mvn package
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We've added simple shell scripts to simplifying running the examples. Now
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that they are built, you can run the server with:
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-```
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+```sh
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$ ./run_greetings_server.sh
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```
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and in another terminal window confirm that it receives a message.
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-```
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+```sh
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$ ./run_greetings_client.sh
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```
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Lisa Carey