We Keep Coding

How can I make my server recognize more than 1 user's login info in java?

Now I do realize there are lots of the same question but even after reading the answers I seem not to undertsand. So here is the code and I'll explain the problem.
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.Objects;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class Server implements Runnable {
String firstName;
String lastName;
String password;
private ArrayList<ConnectionHandler> connections;
private ServerSocket server;
private boolean done;
private ExecutorService pool;
public Server() {
connections = new ArrayList<>();
done = false;
}
#Override
public void run() {
try {
server = new ServerSocket(9999);
pool = Executors.newCachedThreadPool();
while (!done) {
Socket client = server.accept();
ConnectionHandler handler = new ConnectionHandler((client));
connections.add(handler);
pool.execute(handler);
}
} catch (Exception e) {
shutdown();
}
}
public void shutdown() {
try {
done = true;
pool.shutdown();
if (!server.isClosed()) {
server.close();
}
for (ConnectionHandler ch : connections) {
ch.shutdown();
}
} catch (IOException e) {
// ignore
}
}
class ConnectionHandler implements Runnable {
private Socket client;
private BufferedReader in;
private PrintWriter out;
public void broadcast(String message) {
for (ConnectionHandler ch : connections) {
if (ch != null) {
ch.sendMessage(message);
}
}
}
public ConnectionHandler(Socket client) {
this.client = client;
}
#Override
public void run() {
try {
out = new PrintWriter((client.getOutputStream()), true);
in = new BufferedReader(new InputStreamReader(client.getInputStream()));
out.println("To register type 1,to sign in type 2");
//TODO:for loop so only answer is 1 or 2
String message = in.readLine();
switch (message) {
case "1":
out.println("In order to register please enter your first and last name then set a password.");
out.println("Enter first name:");
firstName = in.readLine();
out.println("Enter last name:");
lastName = in.readLine();
out.println("Finally please set a password.");
password = in.readLine();
//TODO: add parameters for passcode
out.println("Now please type 2 to login");
message = in.readLine();
if (message.equals("2")) {
//TODO: copy paste from line 104-x
}
case "2":
out.println("Please enter your first name:");
String messageLogInFN= in.readLine();
out.println("Please enter your last name:");
String messageLogInLN = in.readLine();
out.println("Enter your password:");
String messageLogInPass = in.readLine();
boolean adminAccount = (messageLogInFN.equals("admin") && messageLogInLN.equals("admin") && messageLogInPass.equals("admin123cat"));
if (adminAccount) {
//TODO: add admin permissions
}
boolean Authentication = ((messageLogInFN.equals(firstName) && messageLogInLN.equals(lastName) && messageLogInPass.equals(password)));
if (Authentication) {
out.println("Welcome " + firstName + " " + lastName + "!");
System.out.println(firstName + " " + lastName + " has logged in." );
} else
out.println("Your name or password incorrect!");
}
} catch (IOException e) {
shutdown();
}
}
public void sendMessage(String message) {
out.println(message);
}
public void shutdown() {
try {
in.close();
out.close();
if (!client.isClosed()) {
client.close();
}
} catch (IOException e) {
//ignore
}
}
}
public static void main(String[] args) {
Server server = new Server();
server.run();
}
So I am learning java and saw a tutorial on youtube for a chat room, I programed it following the tutorial, and then I wanted to have a chat room with accounts so I got to coding. Now here is the thing even though I am able to have several devices connected to the server when 2 accounts register the server forgets the first one so there can only be 1 account at the same time. What I am trying to do is have an account system where everyone has their own account that they log in with their first name, last name and passwords. But it doesnt seem to work. How can I make it so that the server doesn't forget all accounts except for the last one that registered?
Edit: Here is the client code if it helps.
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
public class Client implements Runnable {
private boolean done;
private Socket client;
private BufferedReader in;
private PrintWriter out;
#Override
public void run() {
try {
client = new Socket("127.0.0.1", 9999);
out = new PrintWriter((client.getOutputStream()), true);
in = new BufferedReader(new InputStreamReader(client.getInputStream()));
InputHandler inHandler = new InputHandler();
Thread t = new Thread(inHandler);
t.start();
String inMessage;
while ((inMessage = in.readLine()) != null) {
System.out.println(inMessage);
}
} catch (IOException e) {
shutdown();
}
}
public void shutdown() {
done = true;
try {
in.close();
out.close();
if(!client.isClosed()) {
client.close();
}
} catch (IOException e) {
//ignore
}
}
class InputHandler implements Runnable {
#Override
public void run() {
try {
BufferedReader inReader = new BufferedReader(new InputStreamReader(System.in));
while (!done) {
String message = inReader.readLine();
if(message.equals("/quit")) {
out.println(message);
inReader.close();
shutdown();
} else {
out.println(message);
}
}
} catch (IOException e) {
shutdown();
}
}
}
public static void main(String[] args) {
Client client = new Client();
client.run();
}
}
Also as I said most of this isnt my code and I followed a yt tutorial.

websocket client not returning connection

I have websocket server and now i need client to test its usage. I am using this clients code:
import org.msgpack.MessagePack;
import org.springframework.web.socket.BinaryMessage;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
public class TestApp {
public static void main(String[] args) {
try {
// open websocket
final WebsocketClientEndpoint clientEndPoint = new WebsocketClientEndpoint(new URI("ws://localhost:8080/websocket"));
// add listener
clientEndPoint.addMessageHandler(new WebsocketClientEndpoint.MessageHandler() {
public void handleMessage(String message) {
System.out.println(message);
}
});
// send message to websocket
clientEndPoint.sendMessage(new BinaryMessage(...));
// wait 5 seconds for messages from websocket
Thread.sleep(5000);
} catch (InterruptedException ex) {
System.err.println("InterruptedException exception: " + ex.getMessage());
} catch (URISyntaxException ex) {
System.err.println("URISyntaxException exception: " + ex.getMessage());
} catch (IOException e) {
e.printStackTrace();
}
}
}
import org.springframework.web.socket.BinaryMessage;
import java.net.URI;
import javax.websocket.ClientEndpoint;
import javax.websocket.CloseReason;
import javax.websocket.ContainerProvider;
import javax.websocket.OnClose;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.WebSocketContainer;
#ClientEndpoint
class WebsocketClientEndpoint {
Session userSession = null;
private MessageHandler messageHandler;
public WebsocketClientEndpoint(URI endpointURI) {
try {
WebSocketContainer container = ContainerProvider.getWebSocketContainer();
container.connectToServer(this, endpointURI);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Callback hook for Connection open events.
*
* #param userSession the userSession which is opened.
*/
#OnOpen
public void onOpen(Session userSession) {
System.out.println("opening websocket");
this.userSession = userSession;
}
/**
* Callback hook for Connection close events.
*
* #param userSession the userSession which is getting closed.
* #param reason the reason for connection close
*/
#OnClose
public void onClose(Session userSession, CloseReason reason) {
System.out.println("closing websocket");
this.userSession = null;
}
/**
* Callback hook for Message Events. This method will be invoked when a client send a message.
*
* #param message The text message
*/
#OnMessage
public void onMessage(String message) {
if (this.messageHandler != null) {
this.messageHandler.handleMessage(message);
}
}
/**
* register message handler
*
* #param msgHandler
*/
public void addMessageHandler(MessageHandler msgHandler) {
this.messageHandler = msgHandler;
}
/**
* Send a message.
*
* #param message
*/
public void sendMessage(BinaryMessage message) {
this.userSession.getAsyncRemote().sendObject(message);
}
/**
* Message handler.
*
* #author Jiji_Sasidharan
*/
public static interface MessageHandler {
public void handleMessage(String message);
}
}
When i run this client, my sever accepts it, i am using spring and
void afterConnectionEstablished(WebSocketSession session)
method of BinaryWebSocketHandler fires up and everything seems fine, however after this method, the client does not set userSession , it is still null so it always throw nullpointer exception on
this.userSession.getAsyncRemote().sendObject(message);
which is weird cuz server accepts connection. What is causing this problem? Is there a fix for it?
Thanks for help!

package websocket.client;
import java.net.URI;
import javax.websocket.*;
#ClientEndpoint
public class WSClient {
private static Object waitLock = new Object();
#OnMessage
public void onMessage(String message) {
//the new USD rate arrives from the websocket server side.
System.out.println("Received msg: " + message);
}
private static void wait4TerminateSignal() {
synchronized(waitLock) {
try {
waitLock.wait();
} catch (InterruptedException e) {}
}
}
public static void main(String[] args) {
WebSocketContainer container = null; //
Session session = null;
try {
//Tyrus is plugged via ServiceLoader API. See notes above
container = ContainerProvider.getWebSocketContainer();
//WS1 is the context-root of my web.app
//ratesrv is the path given in the ServerEndPoint annotation on server implementation
session = container.connectToServer(WSClient.class, URI.create("ws://localhost:8080/WS1/ratesrv"));
wait4TerminateSignal();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (session != null) {
try {
session.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
}

Class Not-Found exception while running subscriber of Paho Client MQTT

I am trying to implement Pub-Sub using packages in org.eclipse.paho.client.mqttv3-1.2.0.jar
Below int the Subscriber Code:
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttTopic;
import org.eclipse.paho.client.mqttv3.MqttCallback;
import org.eclipse.paho.client.mqttv3.MqttMessage;
import org.eclipse.paho.client.mqttv3.MqttException;
import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import java.net.*;
public class Subscriber {
//public static final String BROKER_URL = "tcp://iot.eclipse.org:1883";
public static final String BROKER_URL = "tcp://localhost:1883";
private MqttClient client;
String topic = "Demo Topic";
public static void main(String[] args) {
System.out.println("MQTT Broker: " + BROKER_URL);
new Subscriber();
}
public Subscriber() {
String clientId = getMacAddress() + "-sub";
System.out.println("Client ID = " + clientId);
try {
client = new MqttClient(BROKER_URL, clientId);
client.connect();
client.setCallback(new SubscribeCallback());
client.subscribe(topic);
} catch (MqttException e) {
e.printStackTrace(); System.exit(1);
}
}
public byte[] getMacAddress(){
byte[] mac = new byte[6];
try{
InetAddress address = InetAddress.getLocalHost();
NetworkInterface nwi = NetworkInterface.getByInetAddress(address);
mac = nwi.getHardwareAddress();
System.out.println(mac);
} catch(Exception e) {
System.out.println(e);
}
return mac;
}
}
class SubscribeCallback implements MqttCallback {
#Override
public void connectionLost (Throwable cause) { }
#Override
public void messageArrived (String topic, MqttMessage message) {
System.out.println("Message arrived. Topic: " + topic
+ " Message: " + message.toString());
if ("I'm gone".equals(topic)) {
System.out.println("Sensor gone!");
}
}
#Override
public void deliveryComplete (IMqttDeliveryToken token) { }
}
I created .class file by executing the following command below
javac -cp org.eclipse.paho.client.mqttv3-1.2.0.jar Subscriber.java
Class file got created without any errors. Next I tried to run the Subscriber class by
java -cp org.eclipse.paho.client.mqttv3-1.2.0.jar Subscriber
I am getting a class not found exception for subscriber
Error: Could not find or load main class Subscriber
Caused by: java.lang.ClassNotFoundException: Subscriber
Note: Both subscriber.java and org.eclipse.paho.client.mqttv3-1.2.0.jar are in same directory

You need to add the current directory to the classpath as well
java -cp .:org.eclipse.paho.client.mqttv3-1.2.0.jar Subscriber
Change the : for ; if running on windows.

Message MQTT not receive in subscribe client

I'm working on MQTT protocol and I try to publish and subscribe with 2 distincts Java applications.
My first application is "Publish". I'm publish on a MQTT server a message.
My second application is "Subscribe". I'm subscribe to a topic and try to receive the message. But I never receive the message.
When I run the 2 applications, I begin with the "Subscribe" application and after I run the "Publish" application. When the "Publish" application begin, I lose my connection to the "Subscribe" application and I can't receive my message.
In the "Subscribe" application, my method messageArrived() is never called by client.setCallback(this). (See the code below).
Here is my 2 code application :
Publish Application :
Class PubClient :
package publishclient;
import java.util.Random;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttConnectOptions;
import org.eclipse.paho.client.mqttv3.MqttCallback;
import org.eclipse.paho.client.mqttv3.MqttMessage;
import org.eclipse.paho.client.mqttv3.MqttException;
import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import org.eclipse.paho.client.mqttv3.MqttAsyncClient;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;
public class PubClient implements MqttCallback {
MqttClient client;
MqttConnectOptions connOpt;
Random rand = new Random();
int nbRandom = 0;
int valMax =151, valMin = 40;
public PubClient() throws MqttException {
String broker = "tcp://88.177.147.17:1883"; // Adress MQTT Server
String clientId = "0bdd-4445-82f3-928f8ddb1887"; // ClientID
String topic1f = "ApplicationRio/capteur"; // Topic
int QoSserveur = 2;
try {
String uuid = "ac8da3c6-0bdd-4445-82f3-928f8ddb3294";
MemoryPersistence persistence = new MemoryPersistence();
// Create 2 objects : client and connOpt
client = new MqttClient(broker, clientId, persistence);
connOpt = new MqttConnectOptions();
connOpt.setCleanSession(true);
client.setCallback(this);
// Connection to MQTT server
System.out.println("Connexion a : " + broker + " Publisher");
client.connect(connOpt);
//Create random number for my message
nbRandom = valMin + rand.nextInt(valMax-valMin);
System.out.println("nb aleatoire = " + nbRandom);
String messageAEnvoyer = uuid + "//" + nbRandom;
System.out.println("Message a envoyer : " + messageAEnvoyer);
MqttMessage message = new MqttMessage();
message.setPayload(messageAEnvoyer.getBytes());
message.setQos(QoSserveur);
client.publish(topic1f, message);
} catch(MqttException e) {
e.printStackTrace();
}
}
#Override
public void connectionLost(Throwable thrwbl) {System.out.println("Perdue connexion");}
#Override
public void messageArrived(String string, MqttMessage mm) throws Exception {
System.out.println("Message recu est : "+ new String(mm.getPayload()));}
#Override
public void deliveryComplete(IMqttDeliveryToken imdt) {
System.out.println("Message delivre au broker");
}
}
The main (Publish) :
package publishclient;
import org.eclipse.paho.client.mqttv3.MqttException;
public class PublishClient {
public static void main(String[] args) throws MqttException {
PubClient publieur = new PubClient();
}
The "subscribe" application :
Class SubClient :
package subscribeclient;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttConnectOptions;
import org.eclipse.paho.client.mqttv3.MqttCallback;
import org.eclipse.paho.client.mqttv3.MqttMessage;
import org.eclipse.paho.client.mqttv3.MqttException;
import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
public class SubClient implements MqttCallback {
MqttClient clientsub;
MqttConnectOptions connOpt;
public SubClient() throws MqttException{
String broker = "tcp://88.177.147.17:1883"; // Adress MQTT Server
String clientId = "0bdd-4445-82f3-928f8ddb1887"; // ClientID
String topic1f = "ApplicationRio/capteur"; // Topic
int QoSserveur = 2;
try{
// Create 2 objects : client and connOpt
clientsub = new MqttClient(broker, clientId);
connOpt = new MqttConnectOptions();
connOpt.setCleanSession(false);
connOpt.setKeepAliveInterval(30);
clientsub.setCallback(this);
// Connection to MQTT Server
System.out.println("Connexion a : " + broker + " Subscriber");
clientsub.connect(connOpt);
clientsub.subscribe(topic1f,QoSserveur);
} catch(MqttException e){
e.printStackTrace();
}
}
#Override
public void connectionLost(Throwable thrwbl) {
System.out.println("Connexion perdue");
}
#Override
public void messageArrived(String string, MqttMessage message) throws Exception {
System.out.println("Le message recu est : " + new String(message.getPayload()));
}
#Override
public void deliveryComplete(IMqttDeliveryToken imdt) {
System.out.println("Message arrive");
}
}
The main (Subscribe) :
package subscribeclient;
import org.eclipse.paho.client.mqttv3.MqttException;
public class SubscribeClient {
public static void main(String[] args) throws MqttException {
SubClient subscriber = new SubClient();
}
}
My 2 applications need to run in the same time, and I don't need to disconnect because I run applications all the time.
So, have you got an idea of why my "Subscribe Client" disconnect when I run the "Publish Client" and why I can't receive my message on my "Subscribe Message" ?
I use org.eclipse.paho.client.mqttv3-1.0.2.jar for the library for MQTT.

Client IDs have to be unique between ALL clients. You have used the same client ID for the publisher and subscriber so the broker will kick the subscriber off when the publisher connects.

Java Tor Lib : How to setup Orchid Tor Lib with Java?

I am trying to implement Orchid Tor lib with Java code; unfortunately and because the lack of documentation I am not able to make it work, this is what I did:
....................
private final static String DEFAULT_SOCKS_PORT = "9050";
TorClient torClient = new TorClient();
torClient.addInitializationListener(new TorInitializationListener() {
#Override
public void initializationProgress(String string, int i) {
System.out.println(">>> [ "+ i + "% ]: "+ string);
// throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
}
#Override
public void initializationCompleted() {
try {
System.out.println("Tor is ready to go!");
setSystemProperties("127.0.0.1","8118");
System.out.println("is online "+isOnline()); //isOnilne is just function return true if connected by pinging google.com
} catch (Exception e) {
e.printStackTrace();
}
}
});
torClient.enableDashboard(8118);
torClient.enableSocksListener(9050);
torClient.start();
private static void setSystemProperties(String host, String port)
{
System.setProperty("proxyHost", host);
System.setProperty("proxyPort", port);
System.setProperty("http.proxyHost", host);
System.setProperty("http.proxyPort", port);
System.setProperty("https.proxyHost", host);
System.setProperty("https.proxyPort", port);
System.setProperty("socks.proxyHost", host);
System.setProperty("socks.proxyPort", DEFAULT_SOCKS_PORT);
System.setProperty("socksProxyHost", host);
System.setProperty("socksProxyPort", DEFAULT_SOCKS_PORT);
}

This seems to work using Java8.
Dependencies: orchid-1.0.0.jar, jsoup-1.8.2.jar & commons-io-2.4.jar
package orchiddemo;
import com.subgraph.orchid.TorClient;
import com.subgraph.orchid.TorInitializationListener;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.net.Socket;
import java.net.URL;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.commons.io.IOUtils;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
public class OrchidDemo {
private static TorClient client;
public static void main(String[] args) {
startOrchid();
}
private static void startOrchid() {
//listen on 127.0.0.1:9150 (default)
client = new TorClient();
client.addInitializationListener(createInitalizationListner());
client.start();
client.enableSocksListener();//or client.enableSocksListener(yourPortNum);
}
private static void stopOrchid() {
client.stop();
}
public static TorInitializationListener createInitalizationListner() {
return new TorInitializationListener() {
#Override
public void initializationProgress(String message, int percent) {
System.out.println(">>> [ " + percent + "% ]: " + message);
}
#Override
public void initializationCompleted() {
System.out.println("Tor is ready to go!");
doTests();
}
};
}
private static void doTests() {
testOrchidUsingProxyObject();
testOrchidUsingSystemPropsProxy();
testOrchidUsingSocket();
}
private static void testOrchidUsingProxyObject() {
Thread thread = new Thread() {
#Override
public void run() {
try {
//Caution: Native Java DNS lookup will occur outside of the tor network.
//Monitor traffic on port 53 using tcpdump or equivalent.
URL url = new URL("https://wtfismyip.com/");
Proxy proxy = new Proxy(Proxy.Type.SOCKS, new InetSocketAddress("localhost", 9150));
HttpURLConnection uc = (HttpURLConnection) url.openConnection(proxy);
uc.setConnectTimeout(10000);
Document document = Jsoup.parse(IOUtils.toString(uc.getInputStream()));
String result = document.select("div[id=tor").text();
System.out.println("testOrchidUsingProxyObject: " + result);
} catch (Exception ex) {
Logger.getLogger(OrchidDemo.class.getName()).log(Level.SEVERE, null, ex);
}
}
};
thread.start();
}
private static void testOrchidUsingSystemPropsProxy() {
Thread thread = new Thread() {
#Override
public void run() {
try {
//Caution: Native Java DNS lookup will occur outside of the tor network.
//Monitor traffic on port 53 using tcpdump or equivalent.
System.setProperty("socksProxyHost", "127.0.0.1");
System.setProperty("socksProxyPort", "9150");
Document document = Jsoup.connect("https://wtfismyip.com/").get();
String result = document.select("div[id=tor").text();
System.out.println("testOrchidUsingSystemPropsProxy: " + result);
System.setProperty("socksProxyHost", "");
System.setProperty("socksProxyPort", "");
} catch (Exception ex) {
Logger.getLogger(OrchidDemo.class.getName()).log(Level.SEVERE, null, ex);
}
}
};
thread.start();
}
private static void testOrchidUsingSocket() {
Thread thread = new Thread() {
#Override
public void run() {
try {
// This does not appear to leak the DNS lookup, but requires confirmation!
Socket socket = client.getSocketFactory().createSocket("www.google.com", 80);
PrintWriter writer = new PrintWriter(socket.getOutputStream(), true);
BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
writer.println("GET /");
String line;
System.out.println("testOrchidUsingSocket: ");
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
socket.close();
} catch (Exception ex) {
Logger.getLogger(OrchidDemo.class.getName()).log(Level.SEVERE, null, ex);
}
}
};
thread.start();
}
}
The DNS leak is a drama, but silvertunnel can help: NetAddressNameService
I'm hoping someone might know of a better way....
Cheers