Problem in starting RMI server, help please

Question

Hi , all:
I am learning RMI from SUN's tutorial. I set all of program packages as same as the tutorial, compiled all of programs . and built all of the jar files, the server classes and the client classes.When I run the server, ComputeEngine, it did not work ,and the following messages are showed at command lines:
C:\RMI\doc>java -Djava.rmi.server.codebase=file:/c:\rmi\ann\public_html\classes/
-Djava.rmi.server.hostname=localhost -Djava.security.policy=java.policy eng
ine.ComputeEngine
ComputeEngine exception: access denied (java.net.SocketPermission 127.0.0.1:1099
connect,resolve)
java.security.AccessControlException: access denied (java.net.SocketPermission 1
27.0.0.1:1099 connect,resolve)
at java.security.AccessControlContext.checkPermission(AccessControlConte
xt.java:272)
at java.security.AccessController.checkPermission(AccessController.java:
399)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:545)
at java.lang.SecurityManager.checkConnect(SecurityManager.java:1044)
at java.net.Socket.<init>(Socket.java:262)
at java.net.Socket.<init>(Socket.java:100)
at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirect
SocketFactory.java:25)
at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMaster
SocketFactory.java:120)
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:499)
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:190
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:174)
at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:318)
at sun.rmi.registry.RegistryImpl_Stub.rebind(Unknown Source)
at java.rmi.Naming.rebind(Naming.java:160)
at engine.ComputeEngine.main(ComputeEngine.java:25)
Please give helps .
Thanks!

Answer 1

You are setting the security policy to the file named
java.policy, make sure that it is in the same
directory where you are invoking the java compiler.Thank.
I have put them at the same directory, but is deos not work.
Something I am not sure.
On the SUN's tutorial , the follows is given:
Win32:
java -Djava.rmi.server.codebase=file:/c:\home\ann\public_html\classes/
-Djava.rmi.server.hostname=zaphod.east.sun.com
-Djava.security.policy=java.policy
engine.ComputeEngine
I changed hostname = localhost
I also changed the code of the server class given by tutorial :
String name = "//host/Compute" ;
to:
String name = "//localhost/Compute";
Should I make such changes?
Here is the server class given by the tutorial:
package engine;
import java.rmi.*;
import java.rmi.server.*;
import compute.*;
public class ComputeEngine extends UnicastRemoteObject
implements Compute
public ComputeEngine() throws RemoteException {
super();
public Object executeTask(Task t) {
return t.execute();
public static void main(String[] args) {
if (System.getSecurityManager() == null) {
System.setSecurityManager(new RMISecurityManager());
String name = "//host/Compute";
try {
Compute engine = new ComputeEngine();
Naming.rebind(name, engine);
System.out.println("ComputeEngine bound");
} catch (Exception e) {
System.err.println("ComputeEngine exception: " +
               e.getMessage());
e.printStackTrace();