Help on remote connection error

[Rudy Yeung]

Grateful if someone can help me out with your expertise on networking coz' I have not figured out what is the cause of the problem though I have already set teh RMI Security Manager. I guess something has been missing which I am not aware of.
When I try instantiating a data class from within the RemoteRequest implementation class for the remote server, I get the following error:
c:\src\assign\scjd\starting> java server.FBNServer
suncertify\db\db.db
Exception in thread "main" java.securoty.AccessControlException: access denied (java.io.FilePermission suncertify\db\db.db write)
at java.security.AccessControlContext.checkPermsssion (Unknown Source)
at java.security.AccessController.checkPermsssion (Unknown Source)
at java.lang.SecurityManager.checkPermission (Unknown Source)
at java.lang.SecurityManager.checkWrite (Unknown Source)
at java.io.File.canWrite(Unknown Source))
at suncertify.db.Data.<init> (Data.java:40)
at server.RemoteRequestImpl.<init> (RemoteRequestImpl.java:17)
at server.FBNServer.main (FBNServer.java:23)

public class FBNServer
{
  public static void main(String args[]) {
    switch (args.length)
    {
      case 0:
        System.out.println("server.FBNServer path\\database_name");
        System.out.println("  e.g. java server.FBNServer suncertify\\db\\db.db");
        System.exit(-1);
        break;
      case 1:
        System.setSecurityManager(new RMISecurityManager());
        try {
          String serverName = "DataServer";
          RemoteRequestImpl rri = new RemoteRequestImpl(args[0]);
          Naming.rebind(serverName, rri);
        } catch (RemoteException e) {
           throw new FlightBookingException(
                  FlightBookingException.E_NETWORK_REMOTEACCESS, 
                                                 e.getMessage());
          }
          catch (MalformedURLException e) {
           throw new FlightBookingException(
                  FlightBookingException.E_NETWORK_MALFORMEDURL, 
                                                 e.getMessage());
          }
          catch (IOException e) {
            throw new FlightBookingException(
                  FlightBookingException.E_DATABASE_CONNECTION, 
                                                e.getMessage());
          }
          System.out.println("FBN Server started successfully");
       default:
          System.out.println("Invalid argumants");
          System.out.println("Please type java client.FBNClient for online help.");
          System.exit(-1);
     }
  }
}

[Debajyoti Pathak]

Rudy,
since you are using a security manager you need to use a policy file wherin you have to specify read write permission for files.
Deb

[Rahul Rathore]

Rudy,
As Debajyoti says a policy file is necessary where you install a Security Manager.
I had found the answer to all my RMI problems in the Core Java Vol-II. Interestingly, the author opines that it setting a security manager on the Server is unnecessary. A Security Manager is useful only on the client.

[Rudy Yeung]

Thank you all.
I finally manage to read/write the database db.db through RMI though the client and server are on running on the same machine. I will try running the client and server on separate machines tomorrow. Afterwards, I only have the very last item to handle: concurrent access.
Without any hassle, I have my policy file set to all permission like the following. Do you guys fine tune the policy file or just set it to all permission like I do?

grant {
permission java.security.AllPermission;
};