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How to configure the netty-SocketIO server so that it is accessible from all remote java clients in jelastic

I am developing a Spring-Boot project which also includes a socketIO server based on netty-socket Io. And therefore two clients: a web client and an android client!
all of them work wonderfully locally! But when I deploy online server in Jelastic only the web client which accesses netty-SocketIO server, but android client fails to connect to netty-SocketIO server. someone could help me configure the netty-socketIO server to accept all requests from any address on port 8888
Server configuration
Configuration config = new Configuration();
//config.setHostname("sec.j.layershift.co.uk");
config.setHostname("0.0.0.0");
config.setPort(8888);
final SocketIOServer server = new SocketIOServer(config);
// Listen for client connections
server.addConnectListener(client -> {
System.out.println("************ Client: " + getIpByClient(client) + " Connected ************");
});
Web client configuration
#CrossOrigin("*")
#RestController
public class ClientLocation {
Socket socket =null;
EventBuilder eventBuilder =null;
Gson gs = new Gson();
//................................
socket = IO.socket("http://sec.j.layershift.co.uk:8888");
socket.on(Socket.EVENT_CONNECT, new Emitter.Listener() {
#Override
public void call(Object... args) {
ChatObject co = new ChatObject("ADMIN", "");
String infUser = gs.toJson(co);
System.out.println("\n"+infUser);
JSONObject jb = new JSONObject();
try {
// jb.put("userName", co.getUserName());
// jb.put("message", co.getMessage());
jb = new JSONObject(infUser);
socket.emit("username", jb);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Configuration of the java or android client
private void clientIO(){
try {
socket = IO.socket("http://aug-sec.j.layershift.co.uk:8888");
socket.on(Socket.EVENT_CONNECT, new Emitter.Listener() {
Nb. the configuration of the java or android client is identical to that of the web because all use the Socket.IO v1.0.0. But only the web client works from the Jelastic host because it is in the same folder as the server and the java clients do not succeed, so everything works in localhost or in LAN

There are 2 possible solutions
You can use the public IP (the way suggested by #Ruslan)
Also, the Jelastic platform resolver supports the WebSocket proxying (if the "Upgrade: websocket" header is present). You can use the JELASTIC_EXPOSE variable to forward the requests from port 80 to 8888 (more info here https://docs.jelastic.com/container-ports/#ports-auto-redirect) inside your container and then just access the app by your environment domain and port 80

remote connection dropped after some time in wildfly

I am using remote connection in java applet using the following code.
Hashtable jndiProps = new Hashtable<Object,Object>();
jndiProps.put(Context.INITIAL_CONTEXT_FACTORY, "org.jboss.naming.remote.client.InitialContextFactory");
jndiProps.put(Context.PROVIDER_URL, "http-remoting://" + myhost + ":" + "8080");
jndiProps.put("jboss.naming.client.ejb.context", true);
jndiProps.put("org.jboss.ejb.client.scoped.context", true);;
//jndiProps.put(Context.URL_PKG_PREFIXES,"org.jboss.ejb.client.naming");
jndiProps.put("endpoint.name", "client-endpoint");
jndiProps.put("remote.connectionprovider.create.options.org.xnio.Options.SSL_ENABLED", false);
jndiProps.put("remote.connections", "default");
jndiProps.put("remote.connection.default.connect.options.org.xnio.Options.SASL_POLICY_NOANONYMOUS", false);
jndiProps.put("remote.connection.default.host", myhost);
jndiProps.put("remote.connection.default.port", "8080");
jndiProps.put(Context.SECURITY_PRINCIPAL, "demouser");
jndiProps.put(Context.SECURITY_CREDENTIALS, "demouser123");
InitialContext ctx = null;
try {
ctx = new InitialContext(jndiProps);
} catch(NamingException nex) {
nex.printStackTrace();
} catch(Exception ex) {
ex.printStackTrace();
}
RemoteInterface remote = (RemoteInterface)ctx.lookup(ejbUrl);
Here the SECURITY_PRINCIPAL is created using the add-user.sh script. The the applet loads, everything works well. But after sometime in java console , a message appears saying
Jul 13, 2016 3:04:21 PM org.jboss.ejb.client.remoting.ChannelAssociation$ResponseReceiver handleEnd
INFO: EJBCLIENT000016: Channel Channel ID 98a848d6 (outbound) of Remoting connection 22d8b2a8 to cms8sf.cdotd.ernet.in/192.168.5.240:8080 can no longer process messages.
And after that , whenever I try to access any method of remote bean Exception in thrown.
java.lang.IllegalStateException: EJBCLIENT000025: No EJB receiver available for handling [appName:app, moduleName:app-ejb, distinctName:] combination for invocation context org.jboss.ejb.client.EJBClientInvocationContext#490f0e4e
at org.jboss.ejb.client.EJBClientContext.requireEJBReceiver(EJBClientContext.java:774)
I am quite unsure why this is happening. Can someone please help me. Thank in advance.
I am using java 1.8 and wildfly 9.0.2.

Perhaps, this option will help you
remote.connection.default.connect.options.org.jboss.remoting3.RemotingOptions.HEARTBEAT_INTERVAL=5000
it's some kind of a ping

How to gracefully shutdown embeded jetty

I have an application runs on an embedded jetty server. Now i want to start/stop the server as a service.
I use a script to start the server.
java $JAVA_OPTS -DREQ_JAVA_VERSION=$JAVA_VERSION -jar myjetty.jar
Main Class
Server server = new Server();
SelectChannelConnector connector = new SelectChannelConnector();
connector.setPort(PORT);
server.addConnector(connector);
HandlerCollection handlers = new HandlerCollection();
NCSARequestLog requestLog = new NCSARequestLog();
requestLog.setFilename(home + "/logs/access_" + logFileDateFormat
+ ".log");
requestLog.setFilenameDateFormat(logFileDateFormat);
requestLog.setRetainDays(10);
requestLog.setAppend(true);
requestLog.setExtended(false);
requestLog.setLogCookies(false);
requestLog.setLogTimeZone(TimeZone.getDefault().getID());
RequestLogHandler requestLogHandler = new RequestLogHandler();
requestLogHandler.setRequestLog(requestLog);
handlers.addHandler(requestLogHandler);
server.setHandler(handlers);
server.start();
server.join();
This starts the server.Stopping and/or Restarting an embedded Jetty instance via web call can be used to stop server but,
How to stop the server from the script? and what changes should i make to shout down server in the main class.

Since Jetty 7.5.x you can use org.eclipse.jetty.server.handler.ShutdownHandler in your code:
Server server = new Server(8080);
HandlerList handlers = new HandlerList();
handlers.setHandlers(new Handler[]
{ someOtherHandler, new ShutdownHandler("secret_password", false, true) });
server.setHandler(handlers);
server.start();
... which will allow you to shut down your jetty by issuing the following http POST request:
curl -X POST http://localhost:8080/shutdown?token=secret_password

You can call setStopTimeout(long timeout) to shutdown Jetty in a relatively graceful way. A statisticsHandler must be configured when calling this method.
Referencing: Jetty Server.class setStopTimeout(long)
e.g.
YourServletHandler servletHandler = new YourServletHandler();
StatisticsHandler statsHandler = new StatisticsHandler();
statsHandler.setHandler(servletHandler);
Server server = new Server(80);
server.setHandler(statsHandler);
server.setStopTimeout(3000L);
//...
server.start();
//...
server.stop();

There is no predefined solution to shut-down the Jetty server. The only ordered way to shut-down the Jetty server is to call the method stop() on the running server instance. You must implement the way how this method is called yourself.
You could achieve this (for example) by...
implementing an RMI server thread and invoke the method from a RMI client
implementing a JMX MBean and from a client call a method on that MBean
implementing a custom handler like described in the link you have posted
If you only want to find a way which does not depend on additional tools like curl, than you could solve it for example like below (it's your own code with small modifications)
public class MyJetty {
public static void main(String[] args) throws Exception {
int PORT = 9103;
String home = System.getProperty("user.home");
String logFileDateFormat = "yyyy_MM_dd";
// execute a request to http://localhost:9103/stop
// instead of `curl -v http://localhost:9103/stop`
if (args.length == 1 && "stop".equalsIgnoreCase(args[0])) {
URL url = new URL("http", "localhost", PORT, "/stop");
try (InputStream in = url.openStream()) {
int r;
while ((r = in.read()) != -1) {
System.out.write(r);
}
return;
} catch (IOException ex) {
System.err.println("stop Jetty failed: " + ex.getMessage());
}
}
Server server = new Server();
SelectChannelConnector connector = new SelectChannelConnector();
connector.setPort(PORT);
server.addConnector(connector);
HandlerCollection handlers = new HandlerCollection();
NCSARequestLog requestLog = new NCSARequestLog();
requestLog.setFilename(home + "/logs/access_" + logFileDateFormat + ".log");
requestLog.setFilenameDateFormat(logFileDateFormat);
requestLog.setRetainDays(10);
requestLog.setAppend(true);
requestLog.setExtended(false);
requestLog.setLogCookies(false);
requestLog.setLogTimeZone(TimeZone.getDefault().getID());
RequestLogHandler requestLogHandler = new RequestLogHandler();
requestLogHandler.setRequestLog(requestLog);
handlers.addHandler(requestLogHandler);
// the class YourHandler is the one from your link
handlers.addHandler(new YourHandler(server));
server.setHandler(handlers);
server.start();
server.join();
}
}
start the server with java MyJetty
stop the server with java MyJetty stop

I don't know why (or if it is a bug) but in my case I had to set shutdownAtStart argument to false to get it working. If I set it as true the Server connector never starts, so it doesn't attend external requests like http://localhost:8888/shutdown?token=secret
new ShutdownHandler("secret", false, false);

java.net.ConnectException while running webservice?

I am developing the web service where in I want to connect to the SOA server. It's giving connection exception.
Code:
public class ConnectSOA{
public static void main(String[] args){
Map<IWorkflowServiceClientConstants.CONNECTION_PROPERTY, String> connProperties = new HashMap<IWorkflowServiceClientConstants.CONNECTION_PROPERTY, String>();
connProperties.put(IWorkflowServiceClientConstants.CONNECTION_PROPERTY.CLIENT_TYPE,WorkflowServiceClientFactory.REMOTE_CLIENT);
connProperties.put(IWorkflowServiceClientConstants.CONNECTION_PROPERTY.EJB_PROVIDER_URL,"t3://10.10.78.79:8001");
connProperties.put(IWorkflowServiceClientConstants.CONNECTION_PROPERTY.EJB_INITIAL_CONTEXT_FACTORY,"weblogic.jndi.WLInitialContextFactory");
try {
workflowServiceClient = WorkflowServiceClientFactory
.getWorkflowServiceClient(connProperties, null, null);
itaskQueryService = workflowServiceClient.getTaskQueryService();
statePredicate = new Predicate(
TableConstants.WFTASK_STATE_COLUMN, Predicate.OP_EQ,
IWorkflowConstants.TASK_STATE_ASSIGNED);
iworkFlowContext = itaskQueryService.authenticate("demouser","demo1".toCharArray(), null);
} catch(Exception e ){
e.printStackTrace();
}
}
}
Exception :
java.net.ConnectException: t3://10.10.78.79:8001 Bootstrap to: hostname/'10.10.78.79:8001' over: 't3' got an error or timed out
I have check the soa server its up and running on the machine.

Can you ping your weblogic?
java weblogic.Admin -url t3://IP:8001 -username xxx -password xxx PING 10
I see that you have 10.10.78.79:8001 and in Exception IP:8001
Could be that your server is not ok. Check the config. See your config.xml and what the listen address for the server is and verify that you can ping it.

Clear ehcache of remote server

How can we clear ehcache on a remote server?
My application is running in staging environment (host 111.22.3.44 and port 17000) and I want to write an utility method that can connect to a given host:port and clear the ehcache of my App. This utility should to work in Windows as well as Linux.
I use JConsole.exe utility to flush the cache of ehcache created in stage-server, but there is a situation where I need to do it programatically.

Hurrey...:) I got the solution for clearing ehcache on a remote environment. Here, I have written a Java utility method that will flush out ehcache of a given remote machine that is specified by host name and port.
public void flushEhcache() throws IOException, NamingException, MalformedObjectNameException, NullPointerException, AttributeNotFoundException, InstanceNotFoundException, MBeanException, ReflectionException {
String host = "111.22.3.44";
String port = "16000";
JMXServiceURL url = new JMXServiceURL("service:jmx:rmi:///jndi/rmi://"
+ host + ":" + port + "/jmxrmi");
JMXConnector jmxc = JMXConnectorFactory.connect(url, null);
MBeanServerConnection mbsc = jmxc.getMBeanServerConnection();
ObjectName beanName = new ObjectName("net.sf.ehcache:type=CacheManager,name=Your Application Name Here");
mbsc.invoke(beanName, "clearAll", new Object[0], new String[0]);
System.out.println("Flushed out ehcache succesfully");
}