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Java WebSocket subscribe/unsubscribe manually from inside server

I have created a simple websocket server with this configuration and I'm trying to subscribe or unsubscribe a user to a certain topic automaticaly, without the user permission (without sending SUBSCRIPTION event from the client). Example: a user connect to the server and the server automatically subscribe the user to topic "news" and "football". I'm trying to replicate what done when a client send this event "SUBSCRIBE\ndestination:/news/e88e2682-c467-4f48-b445-0af9c7983a5d\nid:/news/e88e2682-c467-4f48-b445-0af9c7983a5d\n\n\u0000" but without the client sending it actualy, is it possible?
package com.websocket.socket;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.ChannelRegistration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
import org.springframework.web.socket.config.annotation.WebSocketTransportRegistration;
import org.springframework.web.socket.handler.WebSocketHandlerDecorator;
import org.springframework.web.socket.handler.WebSocketHandlerDecoratorFactory;
import java.util.Arrays;
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfiguration implements WebSocketMessageBrokerConfigurer {
private static final Logger LOGGER = LoggerFactory.getLogger(WebSocketConfiguration.class);
public static final String APP = "/app";
private static final String[] topics = new String[]{
NEWS.BROKER_NAME,
FOOTBALL.BROKER_NAME
};
#Autowired
private TopicChannelInterceptor topicChannelInterceptor;
#Autowired
private UserSessions userSessions;
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config.enableSimpleBroker(topics);
config.setApplicationDestinationPrefixes(APP);
LOGGER.info("Prefix: {}", APP);
LOGGER.info("Topics: {}", Arrays.toString(topics));
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/socket")
.setAllowedOriginPatterns("*")
.withSockJS();
}
#Override
public void configureClientInboundChannel(ChannelRegistration registration) {
registration.interceptors(topicChannelInterceptor);
WebSocketMessageBrokerConfigurer.super.configureClientInboundChannel(registration);
}
#Override
public void configureWebSocketTransport(WebSocketTransportRegistration registration) {
registration.addDecoratorFactory(new WebSocketHandlerDecoratorFactory() {
#Override
public WebSocketHandler decorate(final WebSocketHandler handler) {
return new WebSocketHandlerDecorator(handler) {
#Override
public void afterConnectionEstablished(final WebSocketSession session) throws Exception {
// We will store current user's session into WebsocketSessionHolder after connection is established
userSessions.addUserSession(session.getId(), session);
LOGGER.info("Session stored");
super.afterConnectionEstablished(session);
}
};
}
});
}
}

Spring Boot Autowired Repository null [duplicate]

This question already has answers here:
Why is my Spring #Autowired field null?
(21 answers)
Closed 3 years ago.
I am creating a Netty UDP server using the spring framework. I have 3 classes and 1 interface.
UDPServer.java
package com.example.nettyUDPserver;
import java.net.InetAddress;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.stereotype.Component;
import akka.actor.ActorRef;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioDatagramChannel;
public class UDPServer {
private int port;
ActorRef serverActor = null;
public UDPServer(int port) {
this.port = port;
}
public void run() throws Exception {
final NioEventLoopGroup group = new NioEventLoopGroup();
try {
final Bootstrap b = new Bootstrap();
b.group(group)
.channel(NioDatagramChannel.class)
.option(ChannelOption.SO_BROADCAST, true)
.handler(new ChannelInitializer<NioDatagramChannel>() {
#Override
public void initChannel(final NioDatagramChannel ch) throws Exception {
ChannelPipeline p = ch.pipeline();
p.addLast(new IncomingPacketHandler());
}
});
Integer pPort = port;
InetAddress address = InetAddress.getLocalHost();
//InetAddress address = InetAddress.getByName("192.168.1.53");
System.out.println("Localhost address is: " + address.toString());
b.bind(address, pPort).sync().channel().closeFuture().await();
} finally {
group.shutdownGracefully().sync();
}
}
public static void main(String[] args) throws Exception {
int port = 6001;
new UDPServer(port).run();
}
}
IncomingPacketHandler.java
package com.example.nettyUDPserver;
import java.net.InetAddress;
import java.nio.charset.StandardCharsets;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.stereotype.Component;
import com.example.dao.SensorRepository;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.socket.DatagramPacket;
#ComponentScan("com.example.dao")
public class IncomingPacketHandler extends SimpleChannelInboundHandler<DatagramPacket> {
#Autowired
SensorRepository repo;
IncomingPacketHandler(){
}
#Override
protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket packet) throws Exception {
final InetAddress srcAddr = packet.sender().getAddress();
ByteBuf buffer = packet.content();
packet.replace(buffer);
int len = buffer.readableBytes();
byte[] message = new byte[len];
buffer.readBytes(message);
String str = new String(message, StandardCharsets.UTF_8);
ObjectMapper mapper = new ObjectMapper();
JsonNode actualObj = mapper.readTree(str);
int id = actualObj.get("sensor_id").asInt();
String status = actualObj.get("status").asText();
System.out.println("==========================================================");
System.out.println("Source address of datagram received: " + srcAddr.toString());
System.out.println("String message received: " + str);
show();
}
public void show() {
System.out.println("In show function, we will perform our CRUD operations");
System.out.println(repo);
// try {
// this.repo.findAll().forEach(x -> System.out.println(x));
// } catch (NullPointerException e) {
// e.printStackTrace();
// }
}
}
Sensor.java
package com.example.models;
import javax.persistence.Entity;
import javax.persistence.Id;
#Entity
public class Sensor {
#Id
private int sensor_id;
private String status;
private double batLev;
public int getSensor_id() {
return sensor_id;
}
public void setSensor_id(int sensor_id) {
this.sensor_id = sensor_id;
}
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
public double getBatLev() {
return batLev;
}
public void setBatLev(double batLev) {
this.batLev = batLev;
}
}
SensorRepository.java
package com.example.dao;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;
import com.example.models.Sensor;
#Repository
public interface SensorRepository extends CrudRepository<Sensor, Integer> {
}
I am running my server in the class UDPServer.java and I can successfully get and decode datagrams. The problem is with the SensorRepository in the IncomingPacketHandler.java class. I am using the #Autowired notation in the variable and I am using the #Repository annotation in the interface, but when I print the value of the autowired repository, it is null, so I cannot make SQL queries. Any ideas?
UPDATE
Thank you for your answers guys, much appreciated. I am denoting the IncomingPacketHandler class as a component and I am autowiring it in the UDPServer class. When I run it I get this:
[nioEventLoopGroup-2-1] DEBUG io.netty.channel.DefaultChannelPipeline - Discarded inbound message DatagramPacket(/192.168.61.64:59905 => /192.168.61.64:6001, PooledUnsafeDirectByteBuf(ridx: 0, widx: 38, cap: 2048)) that reached at the tail of the pipeline. Please check your pipeline configuration.
This is probably out of the scope of this question, but you maybe can show me tha direction. Thank you once again.

Your class IncomingPacketHandler is not managed by Spring, but created by you personally:
ChannelPipeline p = ch.pipeline();
p.addLast(new IncomingPacketHandler());
As such, even if you add a million Spring annotations, they won't do anything. What you want instead is to have Spring create this handler, and pass the Spring-created handler as argument to p.addLast

The IncomingPacketHandler class has been created manually and not by Spring and hence bean is not available.
Add #Component to IncomingPacketHandler class:
...
import org.springframework.stereotype.Component;
#Component
public class IncomingPacketHandler extends
...
And then in UDPServer.java:
...
import org.springframework.beans.factory.annotation.Autowired;
#Component
public class UDPServer {
#Autowired
private IncomingPacketHandler incomingPacketHandler;
...

connect to a spring websocket with org.asynchttpclient in java desktop

im trying to make an application who cominicates with a server made in spring-boot with websocket.
My server side configuration is the tutorial of spring-boot websocket
package ar.com.sourcesistemas.armController.websocket;
import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.AbstractWebSocketMessageBrokerConfigurer;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config.enableSimpleBroker("/topic");
config.setApplicationDestinationPrefixes("/app");
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/gs-guide-websocket").withSockJS();
}
}
This is my welcome controller:
package ar.com.sourcesistemas.armController;
import java.util.Map;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
#Controller
public class WelcomeController {
// inject via application.properties
#Value("${welcome.message:test}")
private String message = "Hello World";
#RequestMapping("/")
public String welcome(Map<String, Object> model) {
model.put("message", this.message);
return "welcome";
}
}
and this is the broadcaster:
package ar.com.sourcesistemas.armController;
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.stereotype.Controller;
import ar.com.sourcesistemas.armController.pruebas.Greeting;
import ar.com.sourcesistemas.armController.pruebas.HelloMessage;
#Controller
public class ArmController {
#MessageMapping("/hello")
#SendTo("/topic/greetings")
public Greeting greeting(HelloMessage message) throws Exception {
Thread.sleep(1000); // simulated delay
return new Greeting("Hello, " + message.getName() + "!");
}
}
to connect to this websocket im using org.asynchttpclient, and my code is this:
AsyncHttpClient asyncHttpClient = new DefaultAsyncHttpClient();
String url = "ws://192.168.0.23:8080/gs-guide-websocket/app/topic/greetings";
AsyncHttpClient c = new DefaultAsyncHttpClient();
WebSocket websocket = c.prepareGet(url)
.execute(new WebSocketUpgradeHandler.Builder().addWebSocketListener(new WebSocketTextListener() {
public void onMessage(String message) {
System.out.println(message);
}
public void onOpen(WebSocket websocket) {
System.out.println("imp´rimo websocket");
}
public void onClose(WebSocket websocket) {
System.out.println("ni idea");
}
public void onError(Throwable t) {
}
}).build()).get();
Here i have 2 problems , the first one is :
when i run this program i have an error message in the server side it says "Origin cgeck enabled but transport 'greetings' does not support it".
The second one is:
To made a websocket you have 1 endpoint , in this case is "/gs-guide-websocket", and a broker you can subscribe. All data published in that broker will be broadcasted to all programs subscribed to it. In this case that channel to subscribe will be /app/toppic.
I cant figure out how to subscribe my java desktop application to this message broker.
MORE INFO
I can do this with jquery with this code :
<script src="jquery-3.1.1.min.js"></script>
<script src="sockjs.min.js"></script>
<script src="stomp.min.js"></script>
<script type="text/javascript">
var stompClient = null;
function connect() {
var socket = new SockJS('http://192.168.0.23:8080/gs-guide-websocket');
stompClient = Stomp.over(socket);
stompClient.connect({}, function (frame) {
console.log('Connected: ' + frame);
stompClient.subscribe('/topic/greetings', function (greeting) {
console.log(JSON.parse(greeting.body).content);
});
});
}
function showGreeting(message) {
$("#greetings").append("<tr><td>" + message + "</td></tr>");
}
function disconnect() {
if (stompClient != null) {
stompClient.disconnect();
}
setConnected(false);
console.log("Disconnected");
}
$( document ).ready(function() {
connect();
});
but i cant reply this in a java desktop class.

Websockets Tomcat 7 does not work in existing project

I try to run a websocket server in a Java project that was running on Tomcat6. I have set up a Tomcat 7 server where the project now is running on.
First I tried to run the socket example of Tomcat7. This run perfectly. I copied this class to my old project. When I run the old project again all the functionalities are working like before but only the websocket server doe not work.
This is the ChatAnnotation class that I have copied from the examples from Tomcat to my old project.
import java.io.IOException;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.atomic.AtomicInteger;
import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;
import org.apache.log4j.Logger;
#ServerEndpoint(value = "/websocket/chat")
public class ChatAnnotation {
private static Logger logger = Logger.getLogger(ChatAnnotation.class);
private static final String GUEST_PREFIX = "Guest";
private static final AtomicInteger connectionIds = new AtomicInteger(0);
private static final Set<ChatAnnotation> connections = new CopyOnWriteArraySet<ChatAnnotation>();
private final String nickname;
private Session session;
public ChatAnnotation() {
nickname = GUEST_PREFIX + connectionIds.getAndIncrement();
logger.info("ws instance");
}
#OnOpen
public void start(Session session) {
this.session = session;
connections.add(this);
String message = String.format("* %s %s", nickname, "has joined.");
broadcast(message);
}
#OnClose
public void end() {
connections.remove(this);
String message = String.format("* %s %s", nickname, "has disconnected.");
broadcast(message);
}
#OnMessage
public void incoming(String message) {
// Never trust the client
String filteredMessage = String.format("%s: %s", nickname, message.toString());
broadcast(filteredMessage);
}
#OnError
public void onError(Throwable t) throws Throwable {
logger.error("Chat Error: " + t.toString(), t);
}
private static void broadcast(String msg) {
for (ChatAnnotation client : connections) {
try {
synchronized (client) {
client.session.getBasicRemote().sendText(msg);
}
} catch (IOException e) {
logger.debug("Chat Error: Failed to send message to client", e);
connections.remove(client);
try {
client.session.close();
} catch (IOException e1) {
// Ignore
}
String message = String.format("* %s %s", client.nickname, "has been disconnected.");
broadcast(message);
}
}
}
}
I have noting added in my web.xml. In my old project are also tcpsockets used can this be the problem?
Can anyone help me with this problem?
EDIT
Class added:
import java.util.HashSet;
import java.util.Set;
import javax.websocket.Endpoint;
import javax.websocket.server.ServerApplicationConfig;
import javax.websocket.server.ServerEndpointConfig;
import org.apache.log4j.Logger;
public class ExamplesConfig implements ServerApplicationConfig {
private static Logger log = Logger.getLogger(ChatAnnotation.class);
public Set<ServerEndpointConfig> getEndpointConfigs(Set<Class<? extends Endpoint>> endpointClasses) {
Set<ServerEndpointConfig> result = new HashSet<ServerEndpointConfig>();
log.info("getEndpointConfigs");
return result;
}
public Set<Class<?>> getAnnotatedEndpointClasses(Set<Class<?>> scanned) {
log.info("getAnnotatedEndpointClasses");
return scanned;
}
}

Java websocket server use return value of ServerApplicationConfig interface to deploy programmatic endpoints and for annotated endpoints.
For Tomcat example, if you change the package name of ChatAnnotation. You have to modify websocket.ExamplesConfig too.
public Set<Class<?>> getAnnotatedEndpointClasses(Set<Class<?>> scanned) {
// Deploy all WebSocket endpoints defined by annotations in the examples
// web application. Filter out all others to avoid issues when running
// tests on Gump
Set<Class<?>> results = new HashSet<>();
for (Class<?> clazz : scanned) {
String name = clazz.getPackage().getName();
boolean ok = name.startsWith("websocket.");
if (ok) {
results.add(clazz);
}
}
return scanned;
}
The getAnnotatedEndpointClasses(scanned) only return classes which package name start with websocket. Unmatched classes will not deployed even they have #ServerEndpoint declarations.

SpringWebSockets does not send message from server

Hi i have an issue with spring websockets, this is the scenario:
a standalone application is sending (remote) some data like date Date, procedence String, and weight BigDecimal this data is sending via TCP to socket,
after that this data is saving into database at this point all is fine, but in the next step (websocket) i cannot show this information in a webpage, the weight data must be showed (live) in the screen
this is my websocket configuration:
import java.util.List;
import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.converter.MessageConverter;
import org.springframework.messaging.handler.invocation.HandlerMethodArgumentResolver;
import org.springframework.messaging.handler.invocation.HandlerMethodReturnValueHandler;
import org.springframework.messaging.simp.config.ChannelRegistration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
import org.springframework.web.socket.config.annotation.WebSocketTransportRegistration;
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfiguration implements WebSocketMessageBrokerConfigurer {
#Override
public void registerStompEndpoints(final StompEndpointRegistry registry) {
registry.addEndpoint("/indicator").withSockJS();
}
#Override
public void configureClientInboundChannel(final ChannelRegistration registration) {
}
#Override
public void configureClientOutboundChannel(final ChannelRegistration registration) {
}
#Override
public void configureMessageBroker(final MessageBrokerRegistry registry) {
}
#Override
public void configureWebSocketTransport(WebSocketTransportRegistration wstr) {
}
#Override
public void addArgumentResolvers(List<HandlerMethodArgumentResolver> list) {
}
#Override
public void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> list) {
}
#Override
public boolean configureMessageConverters(List<MessageConverter> list) {
return Boolean.TRUE;
}
}
this is my another class that receive data form socket and process information and send to websocket:
import com.mcss.mcontrols.helper.ByteHelper;
import com.spc.basweb.Constants;
import com.spc.basweb.transmissor.dto.Transmission;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationListener;
import org.springframework.messaging.core.MessageSendingOperations;
import org.springframework.messaging.simp.broker.BrokerAvailabilityEvent;
import com.spc.basweb.service.BroadcastingService;
import com.spc.basweb.service.DataProcessorService;
import java.io.IOException;
import org.springframework.integration.annotation.MessageEndpoint;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.integration.annotation.Transformer;
#MessageEndpoint
public class BroadcastingServiceImpl implements BroadcastingService, ApplicationListener<BrokerAvailabilityEvent> {
private static final Logger LOGGER = Logger.getLogger(BroadcastingServiceImpl.class);
private final MessageSendingOperations<String> messagingTemplate;
private String processedData;
#Autowired
DataProcessorService dataProcessorService;
#Autowired
public BroadcastingServiceImpl(final MessageSendingOperations<String> messagingTemplate) {
this.messagingTemplate = messagingTemplate;
}
#Override
public String getProcessedData() {
return processedData;
}
#Override
#ServiceActivator(inputChannel = "broadcaster")
public String broadcast(byte[] bytes) {
try {
Transmission t = (Transmission) ByteHelper.toObject(bytes);
LOGGER.debug(t.getProcedence() + " " + t.getDate() + " " + t.getWeight());
String rm = this.dataProcessorService.processData(t);
this.messagingTemplate.convertAndSend(Constants.END_POINT_READ, this.dataProcessorService.getWeighing().getWeight().toString());
return rm;
} catch (IOException | ClassNotFoundException ex) {
LOGGER.error("Error de transmision de objetos", ex);
}
return DataProcessorService.NOT_OK_RESPONSE;
}
#Override
public void onApplicationEvent(BrokerAvailabilityEvent e) {
LOGGER.debug("Application event");
}
#Transformer(outputChannel = "broadcaster")
public String convert(String response) {
return response;
}
}
in the debbuger i'm getting this information:
30-03-2016 15:07:20 DEBUG SimpleBrokerMessageHandler:277 - Processing MESSAGE destination=/read session=null payload=3003
in another class (Controller) i'm using the same method:
this.messagingTemplate.convertAndSend(Constants.END_POINT_READ, "3500");
and sending "manually" the information an is showing correctly. and i'm getting in debbuger this message:
30-03-2016 15:05:18 DEBUG SimpleBrokerMessageHandler:277 - Processing MESSAGE destination=/read session=dfR45V77 payload=3500
the difference is in session value but i don't know what this session is having null in the process, what am i doing wrong some clarification o help is welcome

First of all I don't see the configureMessageBroker implementation, so it isn't clear how that may work at all...
From other hand if you see such a difference, try to debug the code in the SimpMessagingTemplate.
I only see headerAccessor.setSessionId(sessionId); in the SimpleBrokerMessageHandler when it does
logger.debug("Broadcasting to " + subscriptions.size() + " sessions.");