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Java RMI permission denied to LAN address, works for 127.0.0.1

I am implementing a Client application and a Server application on my Windows computer using two terminals that communicate with each other.
However I cannot get the Client to run. The Server and Java RMI registry run successfully. I have 3 files: Client.java, Server.java and Hello.java
import java.rmi.registry.LocateRegistry; //Client.java
import java.rmi.registry.Registry;
public class Client {
private Client() {}
public static void main(String[] args) {
String host = (args.length < 1) ? null : args[0];
try {
Registry registry = LocateRegistry.getRegistry("127.0.0.1", 1099);
Hello stub = (Hello) registry.lookup("Hello");
String response = stub.sayHello();
System.out.println("response: " + response);
} catch (Exception e) {
System.err.println("Client exception: " + e.toString());
e.printStackTrace();
}
}
}
import java.rmi.registry.Registry; //Server.java
import java.rmi.registry.LocateRegistry;
import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;
public class Server implements Hello {
public Server() {}
public String sayHello() {
return "Hello, world!";
}
public static void main(String args[]) {
try {
Server obj = new Server();
Hello stub = (Hello) UnicastRemoteObject.exportObject(obj, 0);
// Bind the remote object's stub in the registry
Registry registry = LocateRegistry.getRegistry("127.0.0.1", 1099);
registry.bind("Hello", stub);
System.err.println("Server ready");
} catch (Exception e) {
System.err.println("Server exception: " + e.toString());
e.printStackTrace();
}
}
}
import java.rmi.Remote; //Hello.java
import java.rmi.RemoteException;
public interface Hello extends Remote {
String sayHello() throws RemoteException;
}
All three Java files are located in C:\Program Files\Java\jdk1.8.0_321\bin. After compiling them to the same directory, I run the following commands in the command prompt as administrator.
start rmiregistry -J-Djava.class.path=./
Java RMI registry starts successfully in a new command prompt window (no output).
start java Server
Server starts sucessfully in a new command prompt which outputs "Server ready".
java Client
This command is unsuccessful and outputs the following error:
java.net.SocketException: Permission denied: connect
java.rmi.ConnectIOException: Exception creating connection to: 192.168.1.13; nested exception is:
java.net.SocketException: Permission denied: connect
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:635)
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:216)
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:202)
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:131)
at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:235)
at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:180)
at com.sun.proxy.$Proxy0.sayHello(Unknown Source)
at Client.main(Client.java:15)
Caused by: java.net.SocketException: Permission denied: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:75)
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.PlainSocketImpl.connect(PlainSocketImpl.java:162)
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 sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:40)
at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:148)
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:617)
... 7 more
C:\Program Files\Java\jdk1.8.0_321\bin>_
I am unsure how to get the Client running successfully. I disabled windows firewall and am not using a VPN.

can't run rmi registry on my system

I am learning RMI concepts and had built a simple program taking reference from head first java. All Went fine the first time i ran the code through command prompt.
the next time I ran code the command:
rmiregistry
took too long to load and nothing happened.
I even tried the solution in this thread but nothing happend.
need help to run RMI Registry
also when i run my server and client file i get this error:
Exception: java.rmi.ConnectException: Connection refused to host: 192.168.1.105; nested exception is:
java.net.ConnectException: Connection refused: connect
My Source Code:
myremote.java
import java.rmi.*;
public interface myremote extends Remote
{
public String sayhello() throws RemoteException;
}
Server.java
import java.rmi.*;
import java.rmi.server.*;
public class Server extends UnicastRemoteObject implements myremote
{
public Server() throws RemoteException{}
public String sayhello()
{
return("Server says hi");
}
public static void main(String args[])
{
try
{
myremote S = new Server();
Naming.rebind("remotehello",S);
}
catch(Exception E)
{
System.out.println("Exception: "+E);
}
}
}
client.java
import java.rmi.*;
public class client
{
public static void main(String[] args)
{
client c = new client();
c.go();
}
public void go()
{
try
{
myremote S=(myremote) Naming.lookup("rmi://127.0.0.1/remotehello");
System.out.println("Output:"+S.sayhello());
}
catch(Exception E)
{
System.out.println("Exception: "+ E);
}
}
}

Can't run RMI registry on my system
You've provided no evidence of that.
took too long to load
I don't know what this means. Evidence?
nothing happened.
Nothing is supposed to happen. The RMI registry doesn't print anything. It just sits there.
Run it and try again. You'll be surprised.

RMI(java.net.ConnectException: Connection refused: connect)

I am trying to run my server named SampleServer. I am using windows and this is what i did:
in cmd:
javaw rmiregistry 1099
cd C:\Users\Home\workspace\RMI\src
java -Djava.security.policy=policy SampleServer 1099
i get the following error:
binding //localhost:1099/Sample
New instance of Sample created
Sample server failed:Connection refused to host: localhost; nested exception is:
java.net.ConnectException: Connection refused: connect
I've tried using a different port # such as 4719 for rmiregistry but i receive the same error. I made sure that my firewall was disabled but the problem persist. I made sure that the port is not already being used. I really hope someone can help me.
Picture of my desktop with folders of project, eclipse window and cmd open:
http://s22.postimg.org/uq00qzslr/picyture.png
Code:
SampleServer:
import java.rmi.Naming;
import java.rmi.RemoteException;
import java.rmi.RMISecurityManager;
import java.rmi.server.UnicastRemoteObject;
public class SampleServer {
public static void main(String args[]) {
if (args.length != 1) {
System.err.println("usage: java SampleServer rmi_port");
System.exit(1);
}
// Create and install a security manager
if (System.getSecurityManager() == null)
System.setSecurityManager(new RMISecurityManager());
try {
// first command-line argument is the port of the rmiregistry
int port = Integer.parseInt(args[0]);
String url = "//localhost:" + port + "/Sample";
System.out.println("binding " + url);
Naming.rebind(url, new Sample());
// Naming.rebind("Sample", new Sample());
System.out.println("server " + url + " is running...");
}
catch (Exception e) {
System.out.println("Sample server failed:" + e.getMessage());
}
}
}
SampleClient:
import java.rmi.Naming;
import java.rmi.RemoteException;
public class SampleClient {
public static void main(String args[]) {
try {
if (args.length < 3) {
System.err.println("usage: java SampleClient host port string... \n");
System.exit(1);
}
int port = Integer.parseInt(args[1]);
String url = "//" + args[0] + ":" + port + "/Sample";
System.out.println("looking up " + url);
SampleInterface sample = (SampleInterface)Naming.lookup(url);
// args[2] onward are the strings we want to reverse
for (int i=2; i < args.length; ++i)
// call the remote method and print the return
System.out.println(sample.invert(args[i]));
} catch(Exception e) {
System.out.println("SampleClient exception: " + e);
}
}
}
SampleInterface:
import java.rmi.Remote;
import java.rmi.RemoteException;
public interface SampleInterface extends Remote {
public String invert(String msg) throws RemoteException;
}
Sample:
import java.rmi.Remote;
import java.rmi.RemoteException;
import java.rmi.server.*;
// this is the class with remote methods
public class Sample
extends UnicastRemoteObject
implements SampleInterface {
private int a;
public Sample() throws RemoteException {
System.out.println("New instance of Sample created");
a = 1;
}
public String invert(String m) throws RemoteException {
// return input message with characters reversed
System.out.println("invert("+m+") a=" + a);
return new StringBuffer(m).reverse().toString();
}
}
policy:
grant {
permission java.security.AllPermission;
};

javaw rmiregistry 1099
Stop right there. This is already wrong. 'rmiregistry' is an executable, not the name of a Java class you can execute with 'java' or 'javaw'. Just use 'rmiregistry'.

This error occurs when there is no service running on the port, you are trying to connect. As said by EJP, rmiregistry is a tool which can be started by rmiregistry & in the background (JDK 7). I would recommend you that you check your firewall or connectivity issue with the port.

rmi remote exception. RMI doesnt work

I get a remote exception when I try to run my RMI example. I cannot understand why.
I run the program without any arguments to the program itself or to the JVM.
Please help me to get rid of the exception.
Thanks very much
This is the exception I get:
Server exception: java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
java.lang.ClassNotFoundException: hello.Hello
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
java.lang.ClassNotFoundException: hello.Hello
These are the classes I have:
The client class:
package hello;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
public class Client {
private Client() {}
public static void main(String[] args) {
String host = (args.length < 1) ? null : args[0];
try {
Registry registry = LocateRegistry.getRegistry(host);
Hello stub = (Hello) registry.lookup("Hello");
String response = stub.sayHello();
System.out.println("response: " + response);
} catch (Exception e) {
System.err.println("Client exception: " + e.toString());
e.printStackTrace();
}
}
}
The remote interace:
package hello;
import java.rmi.Remote;
import java.rmi.RemoteException;
public interface Hello extends Remote {
String sayHello() throws RemoteException;
}
And finally the server:
package hello;
import java.rmi.registry.Registry;
import java.rmi.registry.LocateRegistry;
import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;
public class Server implements Hello {
public Server() {}
public String sayHello() {
return "Hello, world!";
}
public static void main(String args[]) {
try {
Server obj = new Server();
Hello stub = (Hello) UnicastRemoteObject.exportObject(obj, 0);
// Bind the remote object's stub in the registry
Registry registry = LocateRegistry.getRegistry("localhost");
registry.bind("Hello", stub);
System.err.println("Server ready");
} catch (Exception e) {
System.err.println("Server exception: " + e.toString());
e.printStackTrace();
}
}
}

Either the Registry or the client or both cannot find the class named in the exception. There are several possible solutions:
include that class in the classpath when executing the Registry and the client. And all the classes it depends on, recursively until closure.
Start the Registry from inside the server JVM, with LocateRegistry.createRegistry(), which solves that classpath problem, and provide the necessary classes on the client's classpath only.
Use the codebase feature to ensure all the system components can access the required server-side classes.

As outlined in the RMI trail
You may need to supply the java.rmi.server.codebase parameter that list all the jars that the RMI server needs to export the objects...
See Running the examples and look at the "Starting the server" section. Also be sure to check out the section on running the client program for additional suggested parameters

How to export files from server to client - Java RMI

I am new to Java RMI and I am simply trying to run a "Hello World" program (code is shown at the end of the message)
Basically, I have a remote class, a remote interface, and a server class in one of my computers and a client class in another computer.
I am trying to get a "hello" message from the server using the client.
The problem is that I cannot compile the client and get it running if I don't have the remote interface and the stub in the same directory where the client is, and at the same time I cannot run the server if I don't have those in the same directory that the server is.
I compiled the server/remote class/interface using javac and then using the rmic compiler.
"rmic Hello".
I am wondering how I could get this to work without having to have all the files in both computers (which is why I want to make it distributed)
Thanks in advance!
Code:
Remote Interface:
import java.rmi.*;
//Remote Interface for the "Hello, world!" example.
public interface HelloInterface extends Remote {
public String say() throws RemoteException;
}
Remote class:
import java.rmi.*;
import java.rmi.server.*;
public class Hello extends UnicastRemoteObject implements HelloInterface {
private String message;
public Hello (String msg) throws RemoteException {
message = msg;
}
public String say() throws RemoteException {
return message;
}
}
Client:
import java.rmi.*;
public class Client
{
public static void main (String[] argv)
{
try
{
HelloInterface hello= (HelloInterface) Naming.lookup(host); //the string representing the host was modified to be posted here
System.out.println (hello.say());
}
catch (Exception e)
{
System.out.println ("Hello Server exception: " + e);
}
}
}
Server:
public static void main (String[] argv) {
try {
Naming.rebind ("Hello", new Hello ("Hello, world!"));
System.out.println ("Hello Server is ready.");
} catch (Exception e) {
System.out.println ("Hello Server failed: " + e);
}
}

My guess would be to simply create identical source at both / either end.

am wondering how I could get this to work without having to have all the files in both computers
You can't. You have to distribute the required class files to the client.
(which is why I want to make it distributed)
Non sequitur.