英文:
Can only make one grpc request then application freezes
问题
以下是您提供的内容的翻译部分：
服务器端实现的方法：
package CarParkOperations.proto.cp;
// ... 导入省略 ...
public class CarParkService extends carParkServiceGrpc.carParkServiceImplBase {
// ... 其他代码省略 ...
public void showStatus(carparkRequest request, StreamObserver<carParkResponse> rStreamObserver) {
// ... 代码省略 ...
}
@Override
public void allCarParks(allCarp rAllCarp, StreamObserver<carParkResponse> rStreamObserver) {
// ... 代码省略 ...
}
public void setFull(CarParkToUpdateRequest request, StreamObserver<carParkResponse> rStreamObserver) {
// ... 代码省略 ...
}
public void setSpaces(CarParkToUpdateRequest request, StreamObserver<carParkResponse> rStreamObserver) {
// ... 代码省略 ...
}
}
客户端实现的方法：
// ... 导入省略 ...
public class YourClientClass {
// ... 其他代码省略 ...
public void showStatus(int id) {
// ... 代码省略 ...
}
public void setFull(int id) {
// ... 代码省略 ...
}
public void allCarParks(String status) {
// ... 代码省略 ...
}
public void setSpaces(int id) {
// ... 代码省略 ...
}
}
Proto 文件：
syntax = "proto3";
package CarParkOperations;
// ... 其他选项省略 ...
service carParkService {
rpc showStatus(carparkRequest) returns (carParkResponse) {};
rpc setFull(CarParkToUpdateRequest) returns (carParkResponse) {};
rpc setSpaces(CarParkToUpdateRequest) returns (carParkResponse) {};
rpc allCarParks(allCarp) returns (stream carParkResponse) {};
}
message CarPark {
int32 carPark_id = 1;
string status = 2;
string location = 3;
}
message carparkRequest {
int32 carPark_id = 1;
}
message CarParkToUpdateRequest {
int32 device_id = 1;
}
message allCarp {
string status = 1;
}
message carParkResponse {
CarPark carPark = 1;
}
希望这些翻译能对您有所帮助。如果您有更多的问题或需要进一步的帮助，请随时提问。
英文:
I am trying to implement a client and server using grpc. When I send a request to the server I get a response but when I try and send another request the application freezes or just continuously says it is looking for the Item that I requested. I'm very new to this so dont know what is going on. this is the methods that I have implemented in my server:
package CarParkOperations.proto.cp;
import java.io.IOException;
import java.util.ArrayList;
import java.util.logging.Logger;
import io.grpc.Server;
import io.grpc.ServerBuilder;
import io.grpc.stub.StreamObserver;
import java.util.Collection;
public class CarParkService extends carParkServiceGrpc.carParkServiceImplBase{
private static final Logger logger = Logger.getLogger(CarParkService.class.getName());
private Server server;
private void start() throws IOException {
/* The port on which the server should run */
int port = 3000;
server = ServerBuilder.forPort(port)
.addService(new CarParkService())
.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");
CarParkService.this.stop();
System.err.println("*** server shut down");
}
});
}
private void stop() {
if (server != null) {
server.shutdown();
}
}
/**
* Await termination on the main thread since the grpc library uses daemon threads.
*/
private void blockUntilShutdown() throws InterruptedException {
if (server != null) {
server.awaitTermination();
}
}
/**
* Main launches the server from the command line.
*/
public static void main(String[] args) throws IOException, InterruptedException {
final CarParkService server = new CarParkService();
server.start();
server.blockUntilShutdown();
}
public void showStatus(carparkRequest request, StreamObserver<carParkResponse> rStreamObserver) {
for(CarParkOperations.proto.cp.CarPark c : Car.getInstance()) {
if(c.getCarParkId() == request.getCarParkId()) {
carParkResponse response = carParkResponse.newBuilder().setCarPark(c).build();
rStreamObserver.onNext(response);
rStreamObserver.onCompleted();
return;
}
}
}
@Override
public void allCarParks(allCarp rAllCarp, StreamObserver<carParkResponse> rStreamObserver) {
ArrayList<CarParkOperations.proto.cp.CarPark> carList = Car.getInstance();
for (CarParkOperations.proto.cp.CarPark car : Car.carparkCar) {
carParkResponse response = carParkResponse.newBuilder().setCarPark(car).build();
if(car.getStatus() == rAllCarp.getStatus()) {
rStreamObserver.onNext(response);
}
}
rStreamObserver.onCompleted();
}
public void setFull(CarParkToUpdateRequest request, StreamObserver<carParkResponse> rStreamObserver) {
ArrayList<CarParkOperations.proto.cp.CarPark> carList = Car.getInstance();
for(CarParkOperations.proto.cp.CarPark c : carList) {
if(c.getCarParkId() == request.getDeviceId()) {
Car.carparkCar.clear();
Car.carparkCar.add(CarParkOperations.proto.cp.CarPark.newBuilder().setCarParkId(c.getCarParkId()).setLocation(c.getLocation()).setStatus("Full").build());
for(CarParkOperations.proto.cp.CarPark car : Car.carparkCar) {
carParkResponse response = carParkResponse.newBuilder().setCarPark(car).build();
rStreamObserver.onNext(response);
rStreamObserver.onCompleted();
return;
}
}
}
}
public void setSpaces(CarParkToUpdateRequest request, StreamObserver<carParkResponse> rStreamObserver) {
ArrayList<CarParkOperations.proto.cp.CarPark> carList = Car.getInstance();
for(CarParkOperations.proto.cp.CarPark c : carList) {
if(c.getCarParkId() == request.getDeviceId()) {
Car.carparkCar.clear();
Car.carparkCar.add(CarParkOperations.proto.cp.CarPark.newBuilder().setCarParkId(c.getCarParkId()).setLocation(c.getLocation()).setStatus("Spaces").build());
for(CarParkOperations.proto.cp.CarPark car : Car.carparkCar) {
carParkResponse response = carParkResponse.newBuilder().setCarPark(car).build();
rStreamObserver.onNext(response);
rStreamObserver.onCompleted();
return;
}
}
}
}
}
These are the methods I implemented in my client:
public void showStatus(int id) {
channel =ManagedChannelBuilder.forAddress("localhost", 3000)
// Channels are secure by default (via SSL/TLS). For the example we disable TLS to avoid
// needing certificates.
.usePlaintext()
.build();
blockingStub = carParkServiceGrpc.newBlockingStub(channel);
asyncStub = carParkServiceGrpc.newStub(channel);
logger.info("Will try to get CarPark " + id + " ...");
carparkRequest request = carparkRequest.newBuilder().setCarParkId(id).build();
carParkResponse response;
try {
response = blockingStub.showStatus(request);
}catch(StatusRuntimeException e) {
logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
return;
}finally {
channel.shutdown();
}
logger.info("Carpark: " + response.getCarPark());
statusArea.append(response.getCarPark().toString());
}
public void setFull(int id) {
channel =ManagedChannelBuilder.forAddress("localhost", 3000)
// Channels are secure by default (via SSL/TLS). For the example we disable TLS to avoid
// needing certificates.
.usePlaintext()
.build();
blockingStub = carParkServiceGrpc.newBlockingStub(channel);
asyncStub = carParkServiceGrpc.newStub(channel);
logger.info("Will try to get CarPark " + id + " ...");
CarParkToUpdateRequest request = CarParkToUpdateRequest.newBuilder().setDeviceId(id).build();
carParkResponse response;
try {
response = blockingStub.setFull(request);
}catch(StatusRuntimeException e) {
logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
return;
}finally {
channel.shutdown();
}
logger.info("Carpark: " + response.getCarPark());
fullArea.append(response.getCarPark().toString());
}
public void allCarParks(String status) {
channel =ManagedChannelBuilder.forAddress("localhost", 3000)
// Channels are secure by default (via SSL/TLS). For the example we disable TLS to avoid
// needing certificates.
.usePlaintext()
.build();
blockingStub = carParkServiceGrpc.newBlockingStub(channel);
asyncStub = carParkServiceGrpc.newStub(channel);
logger.info("Will try to get CarPark " + status + " ...");
allCarp request =
allCarp.newBuilder().setStatus(status).build();
Iterator<carParkResponse> carResponse;
try {
carResponse = blockingStub.allCarParks(request);
for (int i = 1; carResponse.hasNext(); i++) {
carParkResponse carResponse1 = carResponse.next();
info("Result #" + i + ": {0}", carResponse1);
if (testHelper != null) {
testHelper.onMessage(carResponse1);
}
}
} catch(StatusRuntimeException e) {
logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
return;
}
}
public void setSpaces(int id) {
channel =ManagedChannelBuilder.forAddress("localhost", 3000)
// Channels are secure by default (via SSL/TLS). For the example we disable TLS to avoid
// needing certificates.
.usePlaintext()
.build();
blockingStub = carParkServiceGrpc.newBlockingStub(channel);
asyncStub = carParkServiceGrpc.newStub(channel);
logger.info("Will try to get CarPark " + id + " ...");
CarParkToUpdateRequest request = CarParkToUpdateRequest.newBuilder().setDeviceId(id).build();
carParkResponse response;
try {
response = blockingStub.setSpaces(request);
}catch(StatusRuntimeException e) {
logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
return;
}finally {
channel.shutdown();
}
logger.info("Carpark: " + response.getCarPark());
spacesArea.append(response.getCarPark().toString());
}
And this is the proto file:
syntax = "proto3";
package CarParkOperations;
option java_package = "CarParkOperations.proto.cp";
option java_multiple_files = true;
option java_outer_classname = "ClassName";
service carParkService{
rpc showStatus(carparkRequest) returns (carParkResponse) {};
rpc setFull(CarParkToUpdateRequest) returns (carParkResponse){};
rpc setSpaces(CarParkToUpdateRequest) returns (carParkResponse){};
rpc allCarParks(allCarp) returns (stream carParkResponse){};
}
message CarPark{
int32 carPark_id = 1;
string status =2;
string location =3;
}
message carparkRequest{
int32 carPark_id = 1;
}
message CarParkToUpdateRequest {
int32 device_id = 1;
}
message allCarp{
string status = 1;
}
message carParkResponse{
CarPark carPark =1;
}
Like i said I can get a resonse back when I fill in the right request(except for the allCarParks method but thats a separate issue) but when I try do another request is gets stuck. I can send a second response the odd time but thats it. I just want to know where I'm going wrong. Any help would be much appreciated.
答案1
得分: 0
在您的服务器端实现中，不必始终调用onNext()和onCompleted()，例如当列表为空或某些条件不满足时，就会出现错误。
英文:
In your server side implementation, onNext() and onCompleted() are not always to be called, for example when the list is empty or some condition is not met, that's the bug.
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