Develop Reference

Simple SocketHandler for java8 logging(java.util.logging) throws ConnectionException

The intention is to stream the log during runtime on a specific host:port, so that the logs are accessible to users outside the running system, from browser.
As you can see, i have created a simple SocketHandler for java8 logging(java.util.logging), is there something that i have missed?
import java.net.MalformedURLException;
import java.net.URL;
import java.io.IOException;
import java.util.logging.Handler;
import java.util.logging.Level;
import java.util.logging.LogRecord;
import java.util.logging.Logger;
import java.util.logging.SocketHandler;
import java.util.logging.XMLFormatter;
public class Main {
public static void main(String[] args) throws Exception {
Logger logger = Logger.getLogger("concrete.log");
SocketHandler handler = new SocketHandler("HOSTNAME", 19004);
LogRecord logRec = new LogRecord(Level.INFO, "Log recorded");
handler.publish(logRec);
handler.setFormatter(new XMLFormatter());
logger.addHandler(handler);
logger.info("socket handler info message");
}
}
When i run the code, i see the following exception, i have tried checking the system firewall settings on both local(mac/windows) and remote(Linux) and seen that the settings do not block 19004 port
Exception in thread "main" java.net.ConnectException: Connection refused (Connection refused)
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:476)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:218)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:200)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:394)
at java.net.Socket.connect(Socket.java:606)
at java.net.Socket.connect(Socket.java:555)
at java.net.Socket.<init>(Socket.java:451)
at java.net.Socket.<init>(Socket.java:228)
at java.util.logging.SocketHandler.connect(SocketHandler.java:167)
at java.util.logging.SocketHandler.<init>(SocketHandler.java:154)
at Main.main(Main.java:16)
UPDATE
As suggested by bosowski
When i create Socket to listen to a specific port, the log messages are getting printed on the console of the host. However, am unable to access hostname:port for the log to be streamed from the browser. Is there anything specific that needs to be performed after this step?
Please let me know
import java.io.*;
import java.net.*;
public class MyServer {
public static void main(String[] args)
{
try {
ServerSocket ss = new ServerSocket(19004);
Socket soc = ss.accept();
DataInputStream dis
= new DataInputStream(soc.getInputStream());
String str = (String)dis.readUTF();
System.out.println("message= " + str);
ss.close();
}
catch (Exception e) {
System.out.println(e);
}
}
}

SocketHandler does not open up a port to connect to, if that's what you're assuming. It tries to connect to the specified host and port, so you need to have a port that is listening on the host that you are trying to connect to.
https://docs.oracle.com/javase/8/docs/api/java/util/logging/SocketHandler.html#SocketHandler-java.lang.String-int-
<handler-name>.host specifies the target host name to connect to (no default).
<handler-name>.port specifies the target TCP port to use (no default).
If you do indeed have a listening TCP port on the hostname that you're trying to connect to, you can try running sudo nmap -F hostname to check if the port is indeed accessible from your machine.

How to write a secure websocket server in java desktop application

I have a Java Desktop Application, and this application starts a secure websocket server, written in Java. Right now it is using a self-signed certificate which requires the web browser user to manually accept the self-signed certificate to be able to start a client connection to the same websocket server.
I have a SSL certificate for a domain like "mydomain.com", and I'd like to use that SSL certificate to start the Java Desktop Application's secure websocket. Of course the computer will have to point that domain to the local machine, so I added 127.0.0.1 mydomain.com to my HOSTS file (I'm in Windows). Even so, it is not working.
So the question is:
Is it possible to create a Secure Websocket Server from this Java
Desktop Application, so that if my local browser tries to access
wss://mydomain.com/appservices it accepts the certificate as usual
(given the HOSTS file modification) ?, If this is possible, How can I
do that given the following example code?
Additional info and examples of current code
Here is the code that starts the secure websocket server in my Java Desktop App:
package com.mydomain.desktopclient.websockets.server;
import com.mydomain.desktopclient.resources.ResourceLoader;
import com.mydomain.desktopclient.websockets.server.endpoint.RequestServerEndpoint;
import org.eclipse.jetty.server.*;
import org.eclipse.jetty.server.handler.DefaultHandler;
import org.eclipse.jetty.server.handler.HandlerList;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.util.ssl.SslContextFactory;
import org.eclipse.jetty.websocket.jsr356.server.deploy.WebSocketServerContainerInitializer;
import javax.websocket.server.ServerContainer;
import java.net.URL;
public class SecureWebSocketServer {
Server server = null;
public void start() throws Exception {
server = new Server();
int httpsPort = 443;
URL keystore = ResourceLoader.getLocalResourceURL("/resources/misc/keystore/keystore.jks");
SslContextFactory sslContextFactory = new SslContextFactory();
sslContextFactory.setKeyStorePath(keystore.toExternalForm());
sslContextFactory.setCertAlias("mydomain.com.key");
sslContextFactory.setKeyStorePassword("keystorepass");
sslContextFactory.setKeyManagerPassword("keymanagerpass");
sslContextFactory.addExcludeProtocols("SSLv3");
sslContextFactory.addExcludeCipherSuites(".*_GCM_.*");
HttpConfiguration httpsConf = new HttpConfiguration();
httpsConf.setSecurePort(httpsPort);
httpsConf.setSecureScheme("https");
httpsConf.addCustomizer(new SecureRequestCustomizer());
ServerConnector httpsConnector = new ServerConnector(server,
new SslConnectionFactory(sslContextFactory, "http/1.1"),
new HttpConnectionFactory(httpsConf));
httpsConnector.setHost("mydomain.com");
httpsConnector.setPort(httpsPort);
server.addConnector(httpsConnector);
HandlerList baseHandlers = new HandlerList();
server.setHandler(baseHandlers);
ServletContextHandler context = new ServletContextHandler();
// context.setVirtualHosts(new String[] {"mydomain.com"});
context.setContextPath("/");
baseHandlers.addHandler(context);
// Add WebSocket
ServerContainer jsrContainer = WebSocketServerContainerInitializer.configureContext(context);
jsrContainer.setDefaultMaxSessionIdleTimeout(1000 * 60 * 60 * 24);
jsrContainer.addEndpoint(RequestServerEndpoint.class);
Handler handler = new DefaultHandler();
baseHandlers.addHandler(handler);
server.setDumpAfterStart(true);
server.setDumpBeforeStop(true);
try {
server.start();
server.join();
} catch (Throwable t) {
t.printStackTrace(System.err);
}
}
public void stop() throws Exception {
if( server != null ){
server.stop();
server = null;
}
}
}
This code uses jetty-all-9.3.1.v20150714-uber.jar as websocket library.
The class com.mydomain.desktopclient.resources.ResourceLoader is a simple class to find and return files as resources from the app's jar file.
Here is the RequestServerEndpoint if needed:
package com.mydomain.desktopclient.websockets.server.endpoint;
import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.util.logging.Logger;
#ServerEndpoint(value = "/appservices")
public class RequestServerEndpoint {
private static Logger logger = Logger.getLogger(RequestServerEndpoint.class.getName());
#OnOpen
public void onOpen(Session session) {
logger.info("Connected ... " + session.getId());
}
#OnMessage
public String onMessage(String incommingMessage, Session session) {
logger.info("Received Message: \n\n" + incommingMessage);
}
#OnClose
public void onClose(Session session, CloseReason closeReason) {
logger.info(String.format("Session %s closed because of %s", session.getId(), closeReason));
}
}

JBREM000200: Remote connection failed: java.io.IOException: An existing connection was forcibly closed by the remote host

This is my client code
package com.tutorialspoint.test;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Properties;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import com.tutorialspoint.stateless.testRemote;
public class test
{
BufferedReader brConsoleReader = null;
Properties props;
static InitialContext ctx;
{
props = new Properties();
try {
props.load(new FileInputStream("jndi.properties"));
} catch (IOException ex) {
ex.printStackTrace();
}
try {
ctx = new InitialContext(props);
} catch (NamingException ex) {
ex.printStackTrace();
}
brConsoleReader =
new BufferedReader(new InputStreamReader(System.in));
}
public static void main(String[] args)
{
test _test = new test();
try {
testRemote libraryBean =(testRemote)ctx.lookup("java:global/TestEjb/testBean!
com.tutorialspoint.stateless.testRemote");
} catch (NamingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
This is deployed on server
package com.tutorialspoint.stateless;
import javax.ejb.Stateless;
#Stateless
public class testBean implements testRemote
{
public void hello()
{
System.out.println("hello");
}
}
package com.tutorialspoint.stateless;
import javax.ejb.Remote;
#Remote
public interface testRemote
{
void hello();
}
I am getting exception on server side:
19:09:12,676 ERROR [org.jboss.remoting.remote.connection] (Remoting "cognam-
pc-26" read-1) JBREM000200: Remote connection failed:
java.io.IOException: An existing connection was forcibly closed by the
remote host
I am getting exception on client side:-
javax.naming.CommunicationException: Could not obtain connection
to any of these urls: localhost:4447 and discovery failed with error:
javax.naming.CommunicationException: Receive timed out [Root exception
is java.net.SocketTimeoutException: Receive timed out] [Root exception
is javax.naming.CommunicationException: Failed to retrieve stub from
server localhost:4447 [Root exception is java.io.StreamCorruptedException:
invalid stream header: 0000000F]]
org.jnp.interfaces.NamingContext.checkRef(NamingContext.java:1414)
at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:594)
at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:587)
at javax.naming.InitialContext.lookup(InitialContext.java:392)
at com.tutorialspoint.test.test.main(test.java:37)

It might be that your server is not actually allowing connections to 4447. Check if you can telnet to that port or use netstat -an to query this.
Also ensure that there is no firewall blocking access to the port.

Try shutdown any http traffic capture tools if running (e.g. Fiddler)

Google Cloud Connection Server and smack

I'm trying to get a java server set up for communicating to Google's Cloud Connection Server using the smack library. I have set up an app ID and API key through Google APIs and am trying to use the following code:
import javax.net.ssl.SSLSocketFactory;
import org.jivesoftware.smack.Connection;
import org.jivesoftware.smack.ConnectionConfiguration;
import org.jivesoftware.smack.PacketListener;
import org.jivesoftware.smack.SASLAuthentication;
import org.jivesoftware.smack.XMPPConnection;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.packet.Packet;
public class CloudMessager {
public CloudMessager(){
ConnectionConfiguration config = new ConnectionConfiguration("gcm.googleapis.com", 5235);
SASLAuthentication.supportSASLMechanism("PLAIN", 0);
config.setSASLAuthenticationEnabled(true);
config.setSocketFactory(SSLSocketFactory.getDefault());
Connection connection = new XMPPConnection(config);
// Connect to the server
try {
connection.connect();
connection.login("SENDERID#gcm.googleapis.com", "APIKEY");
PacketListener myListener = new PacketListener() {
public void processPacket(Packet packet) {
}
};
// Register the listener.
connection.addPacketListener(myListener,null);
} catch (XMPPException e) {
e.printStackTrace();
}
}
}
Which gives me the following error:
SASL authentication PLAIN failed: text:
at org.jivesoftware.smack.SASLAuthentication.authenticate(SASLAuthentication.java:342)
at org.jivesoftware.smack.XMPPConnection.login(XMPPConnection.java:221)
at org.jivesoftware.smack.Connection.login(Connection.java:366)
at org.umptyfratz.strongbox.CloudMessager.<init>(CloudMessager.java:25)
I'm at a bit of a loss to figure out where to go from here. Has anyone else successfully connected to CCS using the Java smack library?

Try to debug the connection with this option:
config.setDebuggerEnabled(true);
This'll open a new window with the data sent and received.
If you find something like "Project SENDERID not whitelisted." you have to register your project here.
(This is in the documentation's note too! http://developer.android.com/google/gcm/ccs.html )

Create WebSphere administrative client program for java

I am using IBM WebSphere server. I need to Create WebSphere administrative client program for java using WebSphere Administrative API's. I am using this code for creating admin client
...
adminClient = AdminClientFactory.createAdminClient(connectProps);
...
but it gives exception.
The system cannot create a SOAP connector to connect to host localhost at port 8881.
After creating client I want to configure WASADMIN through this API. Am I on right track?
I need to get shared library through this API.

check if you have this server SOAP connector port set to 8881.
In Dmgr click the server name than Ports to check it. If not using 8881 than change it to the correct port being used by the server you're trying to connect to.
Update:
I did a test in my environment(Linux) and the following code worked( I had to add WebSphere_ND8.5/AppServer/runtimes/com.ibm.ws.admin.client_8.5.0.jarto classpath to run it without getting a ClassNotFoundException):
import java.util.Properties;
import java.util.logging.Logger;
import com.ibm.websphere.management.AdminClient;
import com.ibm.websphere.management.AdminClientFactory;
import com.ibm.websphere.management.exception.ConnectorException;
public class AdminConnect {
private static Logger logger = Logger.getLogger(AdminConnect.class.getName());
/**
* #param args
*/
public static void main(String[] args) {
Properties connectProps = new Properties();
connectProps.setProperty(
AdminClient.CONNECTOR_TYPE, AdminClient.CONNECTOR_TYPE_SOAP);
connectProps.setProperty(AdminClient.CONNECTOR_HOST, "localhost");
connectProps.setProperty(AdminClient.CONNECTOR_PORT, "8880");
// connectProps.setProperty(AdminClient.USERNAME, "test2");
// connectProps.setProperty(AdminClient.PASSWORD, "user24test");
AdminClient adminClient = null;
try
{
adminClient = AdminClientFactory.createAdminClient(connectProps);
logger.info("Connected successfuly with WebSphere :) ");
}
catch (ConnectorException e)
{
logger.severe("Exception creating admin client: " + e);
e.printStackTrace();
}
}
}