i wan't to create a chat so i have server and client; server code:
serverSocket = new ServerSocket(8080);
mainSocket = serverSocket.accept();
out = new PrintWriter(mainSocket.getOutputStream());
in = new BufferedReader(new InputStreamReader(mainSocket.getInputStream()));
gui = new JavaFXGUI();
gui.setIn(in);
gui.setOut(out);
gui.run()
client code:
clientSocket = new Socket("127.0.0.1", 8080);
out = new PrintWriter(clientSocket.getOutputStream());
in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
gui = new JavaFXGUI();
gui.setIn(in);
gui.setOut(out);
gui.run()
JavaFXGUI :
public class JavaFXGUI extends Application{
private BufferedReader in;
private PrintWriter out;
private ChatController chatController;
#Override
public void start(Stage primaryStage) throws Exception {
FXMLLoader loader = new FXMLLoader();
URL xmlUrl = getClass().getResource("/GUI/scenes/mainScene.fxml");
loader.setLocation(xmlUrl);
System.out.println(in);
chatController = new ChatController(out,in);
loader.setController(chatController);
Parent root = loader.load();
primaryStage.setTitle("Chat");
primaryStage.setWidth(800);
primaryStage.setHeight(450);
primaryStage.setScene(new Scene(root));
primaryStage.show();
}
public void run() {
launch();
}
public void setIn(BufferedReader in) {
this.in = in;
}
public void setOut(PrintWriter out) {
this.out = out;
}
}
so the problem is that in start method in and out parameters are null, why is this hapenning and how can i fix it. (i tried to pass in and out in constructor but it throws an error)
Related
I'm writing a simple tcp server for short connection.
I have two vertical.
One handling the tcp request, get the eventBus and send the message to it.
Another vertical just consume and reply it.
The question is.Tcp client can't receive the result.I know the eventBus.request() is async.But don't know how to control it,just let the socket waiting for the result.
main
package org.example;
import io.vertx.core.DeploymentOptions;
import io.vertx.core.Vertx;
import io.vertx.core.VertxOptions;
public class Application {
public static void main(String[] args) {
VertxOptions options = new VertxOptions();
options.setEventLoopPoolSize(1);
Vertx vertx = Vertx.vertx(options);
DeploymentOptions ruleOptions = new DeploymentOptions();
ruleOptions.setWorker(true);
ruleOptions.setInstances(1);
vertx.deployVerticle("org.example.RuleVertical", ruleOptions);
DeploymentOptions serverOptions = new DeploymentOptions();
serverOptions.setInstances(1);
vertx.deployVerticle("org.example.ServerVertical", serverOptions);
}
}
server vertical
package org.example;
import io.vertx.core.AbstractVerticle;
import io.vertx.core.eventbus.EventBus;
import io.vertx.core.net.NetServer;
public class ServerVertical extends AbstractVerticle {
#Override
public void start() throws Exception {
EventBus eventBus = vertx.eventBus();
NetServer netServer = vertx.createNetServer();
netServer.connectHandler(socket -> {
socket.handler(buffer -> {
eventBus.request("message.id", buffer.toString(), reply -> {
System.out.println("Server reply: " + reply.result().body());
socket.write(reply.result().body().toString()).onFailure(event -> event.printStackTrace());
});
});
});
netServer.listen(1234);
}
}
rule vertical
package org.example;
import io.vertx.core.AbstractVerticle;
import io.vertx.core.eventbus.EventBus;
public class RuleVertical extends AbstractVerticle {
#Override
public void start() throws Exception {
EventBus eventBus = vertx.eventBus();
eventBus.consumer("message.id", message -> {
try {
Thread.sleep(2000);
message.reply("hello");
} catch (InterruptedException e) {
e.printStackTrace();
}
});
}
}
client
package org.example;
import java.io.*;
import java.net.Socket;
public class Client {
public static void main(String[] args) throws IOException {
Socket socket = new Socket("127.0.0.1", 1234);
OutputStream outputStream = socket.getOutputStream();
PrintWriter printWriter = new PrintWriter(outputStream);
System.out.println("Request: 1234");
printWriter.write("1234");
printWriter.flush();
socket.shutdownOutput();
InputStream inputStream = socket.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
String line = null;
StringBuilder sb = new StringBuilder();
while ((line = reader.readLine()) != null) {
sb.append(line);
}
System.out.println("Response: " + sb);
reader.close();
printWriter.close();
inputStream.close();
outputStream.close();
socket.close();
}
}
Server log
Server reply: hello
io.netty.channel.StacklessClosedChannelException
at io.netty.channel.AbstractChannel$AbstractUnsafe.write(Object, ChannelPromise)(Unknown Source)
Client log
Request: 1234
Response:
My parameter (workingDirectory) is always null and I do not understand why?
I am using the job launcher to kick off the job.
I see the job parameter in the database but it is not getting injected into my reader.
This is my reader.
#Component("customerReader")
#StepScope
public class CustomReader implements ItemReader<Customer> {
#Value("#{jobParameters['workingDirectory']}")
protected String workingDirectory;
private BufferedReader reader;
protected ObjectMapper objectMapper = new ObjectMapper();
private int fileIdx = 1;
#Override
public Customer read() throws IOException {
if(reader == null) {
reader = new BufferedReader(new FileReader(new File(workingDirectory + "output1.json")));
}
String line = reader.readLine();
if (line == null) {
try {
fileIdx++;
reader = new BufferedReader(
new FileReader(new File(workingDirectory + "output" + fileIdx + ".json")));
}
catch (FileNotFoundException ex) {
return null;
}
line = reader.readLine();
}
return objectMapper.readValue(line, Customer.class);
}
}
I am launching by calling:
JobParameters p = new JobParametersBuilder().addString("workingDirectory", workingDirectory).toJobParameters();
JobExecution e = jobLauncher.run(
recordGenerator.getJob(file, "/Users/abc/data/"), p);
I am learning zookeeper and trying out the Curator framework for service discoveries. However, I am facing a weird issue that I have difficulties to figure out. The problem is when I tried to register an instance via serviceDiscovery, the cacheChanged event of the serviceCache gets triggered three times. When I removed an instance, it is only triggered once, which is the expected behavior. Please see the code below:
public class DiscoveryExample {
private static String PATH = "/base";
static ServiceDiscovery<InstanceDetails> serviceDiscovery = null;
public static void main(String[] args) throws Exception {
CuratorFramework client = null;
try {
// this is the ip address of my VM
client = CuratorFrameworkFactory.newClient("192.168.149.129:2181", new ExponentialBackoffRetry(1000, 3));
client.start();
JsonInstanceSerializer<InstanceDetails> serializer = new JsonInstanceSerializer<InstanceDetails>(
InstanceDetails.class);
serviceDiscovery = ServiceDiscoveryBuilder.builder(InstanceDetails.class)
.client(client)
.basePath(PATH)
.serializer(serializer)
.build();
serviceDiscovery.start();
ServiceCache<InstanceDetails> serviceCache = serviceDiscovery.serviceCacheBuilder()
.name("product")
.build();
serviceCache.addListener(new ServiceCacheListener() {
#Override
public void stateChanged(CuratorFramework curator, ConnectionState state) {
// TODO Auto-generated method stub
System.out.println("State Changed to " + state.name());
}
// THIS IS THE PART GETS TRIGGERED MULTIPLE TIMES
#Override
public void cacheChanged() {
System.out.println("Cached Changed ");
List<ServiceInstance<InstanceDetails>> list = serviceCache.getInstances();
Iterator<ServiceInstance<InstanceDetails>> it = list.iterator();
while(it.hasNext()) {
System.out.println(it.next().getAddress());
}
}
});
serviceCache.start();
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
System.out.print("> ");
String line = in.readLine();
} finally {
CloseableUtils.closeQuietly(serviceDiscovery);
CloseableUtils.closeQuietly(client);
}
}
}
AND
public class RegisterApplicationServer {
final static String PATH = "/base";
static ServiceDiscovery<InstanceDetails> serviceDiscovery = null;
public static void main(String[] args) throws Exception {
CuratorFramework client = null;
try {
client = CuratorFrameworkFactory.newClient("192.168.149.129:2181", new ExponentialBackoffRetry(1000, 3));
client.start();
JsonInstanceSerializer<InstanceDetails> serializer = new JsonInstanceSerializer<InstanceDetails>(
InstanceDetails.class);
serviceDiscovery = ServiceDiscoveryBuilder.builder(InstanceDetails.class).client(client).basePath(PATH)
.serializer(serializer).build();
serviceDiscovery.start();
// SOME OTHER CODE THAT TAKES CARES OF USER INPUT...
} finally {
CloseableUtils.closeQuietly(serviceDiscovery);
CloseableUtils.closeQuietly(client);
}
}
private static void addInstance(String[] args, CuratorFramework client, String command,
ServiceDiscovery<InstanceDetails> serviceDiscovery) throws Exception {
// simulate a new instance coming up
// in a real application, this would be a separate process
if (args.length < 2) {
System.err.println("syntax error (expected add <name> <description>): " + command);
return;
}
StringBuilder description = new StringBuilder();
for (int i = 1; i < args.length; ++i) {
if (i > 1) {
description.append(' ');
}
description.append(args[i]);
}
String serviceName = args[0];
ApplicationServer server = new ApplicationServer(client, PATH, serviceName, description.toString());
server.start();
serviceDiscovery.registerService(server.getThisInstance());
System.out.println(serviceName + " added");
}
private static void deleteInstance(String[] args, String command, ServiceDiscovery<InstanceDetails> serviceDiscovery) throws Exception {
// in a real application, this would occur due to normal operation, a
// crash, maintenance, etc.
if (args.length != 2) {
System.err.println("syntax error (expected delete <name>): " + command);
return;
}
final String serviceName = args[0];
Collection<ServiceInstance<InstanceDetails>> set = serviceDiscovery.queryForInstances(serviceName);
Iterator<ServiceInstance<InstanceDetails>> it = set.iterator();
while (it.hasNext()) {
ServiceInstance<InstanceDetails> si = it.next();
if (si.getPayload().getDescription().indexOf(args[1]) != -1) {
serviceDiscovery.unregisterService(si);
}
}
System.out.println("Removed an instance of: " + serviceName);
}
}
I appriciate if anyone can please point out where I am doing wrong and maybe can share some good materials/examples so I can refer to. The official website and the examples on github does not help a lot.
I have this dummy program:
package com.company;
import javax.net.ssl.*;
import java.io.*;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketTimeoutException;
import java.security.*;
import java.security.cert.CertificateException;
class MyClass implements Serializable
{
private int i,j;
public MyClass(int i, int j)
{
this.i = i;
this.j = j;
}
public int getJ()
{
return j;
}
public void setJ(int j)
{
this.j = j;
}
public int getI()
{
return i;
}
public void setI(int i)
{
this.i = i;
}
}
class SSLContextHelper
{
static SSLContext createSSLContext(String path) throws KeyStoreException, UnrecoverableKeyException, NoSuchAlgorithmException, IOException, KeyManagementException, CertificateException
{
KeyStore keyStore = KeyStore.getInstance("PKCS12");
keyStore.load(new FileInputStream(path),"DSL2137976".toCharArray());
// Create key manager
KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("SunX509");
keyManagerFactory.init(keyStore, "DSL2137976".toCharArray());
KeyManager[] km = keyManagerFactory.getKeyManagers();
// Create trust manager
TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance("SunX509");
trustManagerFactory.init(keyStore);
TrustManager[] tm = trustManagerFactory.getTrustManagers();
// Initialize SSLContext
SSLContext sslContext = SSLContext.getInstance("TLSv1.2");
sslContext.init(km, tm, new SecureRandom());
return sslContext;
}
}
class ServerThread extends Thread
{
ServerSocket server;
Socket client;
ObjectOutputStream out;
ObjectInputStream in;
boolean issecure;
SSLContext sslContext;
public ServerThread(int port, boolean issecure) throws IOException, UnrecoverableKeyException, CertificateException, NoSuchAlgorithmException, KeyStoreException, KeyManagementException
{
this.issecure=issecure;
client=null;
if(issecure)
{
sslContext = SSLContextHelper.createSSLContext("/usr/lib/jvm/java-8-openjdk/jre/lib/security/ssltest");
SSLServerSocketFactory sslServerSocketFactory = sslContext.getServerSocketFactory();
server = sslServerSocketFactory.createServerSocket(port);
server.setSoTimeout(200);
}
else
server=new ServerSocket(port);
}
#Override
public void run()
{
while (true)
{
try
{
if(client==null)
{
if (issecure)
{
SSLSocket clientssl = (SSLSocket) server.accept();
clientssl.setEnabledCipherSuites(clientssl.getSupportedCipherSuites());
clientssl.startHandshake();
client = clientssl;
}
else
client = server.accept();
in = new ObjectInputStream(client.getInputStream());
out = new ObjectOutputStream(client.getOutputStream());
client.setSoTimeout(200);
}
String[] req = in.readUTF().split("\n");
out.writeUTF("hello I'm the server");
out.flush();
req = in.readUTF().split("\n");
out.writeUTF("I mean I'll serve you");
out.flush();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
}
public class Main
{
public static void main(String... args) throws IOException, ClassNotFoundException, UnrecoverableKeyException, CertificateException, NoSuchAlgorithmException, KeyStoreException, KeyManagementException
{
ServerThread serverThread=new ServerThread(14200, true);
serverThread.setDaemon(true);
serverThread.start();
ServerThread mail=new ServerThread(14201, false);
mail.setDaemon(true);
mail.start();
try
{
Thread.sleep(5000);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
SSLSocket client=(SSLSocket)SSLContextHelper.createSSLContext("/usr/lib/jvm/java-8-openjdk/jre/lib/security/ssltest").getSocketFactory().createSocket();
client.connect(new InetSocketAddress("localhost",14200),5000);
Socket mailclient = new Socket();
mailclient.connect(new InetSocketAddress("localhost", 14201), 5000);
client.startHandshake();
client.setSoTimeout(5000);
ObjectOutputStream out = new ObjectOutputStream(client.getOutputStream());
ObjectInputStream in = new ObjectInputStream(client.getInputStream());
out.writeUTF("hello\nhow are you");
out.flush();
System.out.println(in.readUTF());
out.writeUTF("what\nI didn't understand");
out.flush();
System.out.println(in.readUTF());
int i=0;
while (i<=1)
{
try
{
try
{
Thread.sleep(10000);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
out.writeUTF("hello\nhow are you");
out.flush();
System.out.println(in.readUTF());
out.writeUTF("what\nI didn't understand");
out.flush();
System.out.println(in.readUTF());
i++;
}
catch (SocketTimeoutException ignored)
{
}
}
}
}
It's just a simulation of a real program I have, the Thread.sleep on the client side is a simulation of a user doing some interaction with the system before clicking a button(the first sleep is the simulation of the user putting the sign in information, the second sleep is the user opening tab,clicking link,answers dialogs,etc).
Unfortunately I'm getting EOFException in the server side right after the server.accept succeed(that is when the client connects).
I know that this exception occurs when there is no data to get but this happens even after these two lines(the first ones before the while loop) on the client side:
out.writeUTF("hello\nhow are you");
out.flush();
after these two lines the client waits 5 seconds(the timeout I put) , during this 5 seconds the server keeps on its EOFException, when the timeout finishes the client gets SocketTimeoutException and the program exits.
The original program is getting the same EOFException on the server side, it began when I moved to SSLSockets.
So what's the issue here ?
Edit
I have found that when I remove the timeout(the Read timeout not the Accept timeout) it works perfectly.
Playing with the timeout, setting it to different value gives me strange NullPointerExceptions(that in is null !!!!!!!!!!).
I need the timeout because in my real program the server won't wait the client forever, it has other clients to serve as well .
Why timeout causes this ?
I am quite new to Java so I need some help. I am trying to make a Notepad application.
The problem is that none of my menus or textfield is showing up. I cannot figure out what the problem is. Please help.
public class NotePad extends JFrame implements ActionListener {
private JTextArea txtArea;
private JMenuBar mnuBar;
private JMenu mnyFile, mnyFormat, mnyEdit, mnyHelp;
private JMenuItem openFile, saveFile, exit, textWrap, noTextWrap, clear, abtNotepad;
public NotePad() {
setTitle("NOTEPAD");
setSize(700, 500);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLayout(new BorderLayout());
//Tekstboks
txtArea = new JTextArea();
//MenyBar
mnuBar = new JMenuBar();
//Meny
mnyFile = new JMenu("File");
mnyFormat = new JMenu("Format");
mnyEdit = new JMenu("Edit");
mnyHelp = new JMenu("Help");
//UnderMeny
openFile = new JMenuItem("Open");
saveFile = new JMenuItem("Save");
exit = new JMenuItem("Exit");
textWrap = new JMenuItem("Text Wrap");
noTextWrap = new JMenuItem("No Text Wrap");
clear = new JMenuItem("Clear");
abtNotepad = new JMenuItem("About Notepad");
add(txtArea);
add(mnuBar);
add(mnyFile);
add(mnyFormat);
add(mnyEdit);
add(mnyHelp);
add(openFile);
add(saveFile);
add(exit);
add(textWrap);
add(noTextWrap);
add(clear);
add(abtNotepad);
setJMenuBar(mnuBar);
setVisible(true);
}
public static void main(String[] args) {
new NotePad();
}
public void actionPerformed(ActionEvent e) {
}
}
Your constructor should look something like:
public NotePad() {
setTitle("NOTEPAD");
setSize(700, 500);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLayout(new FlowLayout());
txtArea = new JTextArea();
mnuBar = new JMenuBar();
mnyFile = new JMenu("File");
mnyFormat = new JMenu("Format");
mnyEdit = new JMenu("Edit");
mnyHelp = new JMenu("Help");
openFile = new JMenuItem("Open");
saveFile = new JMenuItem("Save");
exit = new JMenuItem("Exit");
textWrap = new JMenuItem("Text Wrap");
noTextWrap = new JMenuItem("No Text Wrap");
clear = new JMenuItem("Clear");
abtNotepad = new JMenuItem("About Notepad");
mnuBar.add(mnyFile);
mnuBar.add(mnyFormat);
mnuBar.add(mnyEdit);
mnuBar.add(mnyHelp);
mnyFile.add(openFile);
mnyFile.add(saveFile);
mnyFile.add(exit);
mnyFormat.add(textWrap);
mnyFormat.add(noTextWrap);
mnyEdit.add(clear);
mnyHelp.add(abtNotepad);
setJMenuBar(mnuBar);
add(txtArea);
setVisible(true);
}
Otherwise you are overriding each component you add to BorderLayout.