NFS time out

[Frank Hamilton]

hi

I need to implement a timeout in my nfs client that is implemented inside a servlet.
This is my code:

XFile file = new XFile(serverPath+filePaht);
file.exists();

If the nfs server is down the file.exists() method wait for response for a long time.
How can I implement a time out for avoid this.

Thank in advance.

[Rob Spoor]

You'll want to include a link to the library you're using next time; you should TellTheDetails. I now got that information from your earlier thread. Not that that got me far, without public Javadoc pages...

[Frank Hamilton]

Thank Rob, yes I should TellTheDetails.

Inside my servlet I use webnfs and j-ftp for creating a nfs client and access to a remote directory. I need a time out when the nfs server is down but I think this api don't give me any mechanism for me pourpose. Therefore I think any mechanism, maybe a thread.
This is my code:

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {  
        String user=properties.getProperty("user");  
        String serverPath=properties.getProperty("nfshome");  
        String initialUser=user.substring(0, 1);  
        String filePaht=year+"/"+month+"/"+initialUser+"/"+user+".pdf";  
        XFile file = new XFile(serverPath+filePaht);  
        boolean exists=file.exists();  
   }  

file.exist() method it's waiting for the connexion and if the nfs is down this method never terminate.

Anybody can help me with this problem?. I think nsf is over tcp protocolo and maybe can use some tcp connector method try to connect with nfs server and if the server is down this method throw a timeout.

TIA

[Rob Spoor]

Sounds like you want to use Callable and Future:

final XFile file = new XFile(serverPath+filePaht); // final so it can be used in the anonymous inner class
Callable<Boolean> callable = new Callable<Boolean>()
{
    public Boolean call()
    {
        return file.exists();
    }
};
ExecutorService service = Executors.newSingleThreadExecutor();
try
{
    Future<Boolean> future = service.submit(callable);
    return future.get(...); // add timeout settings; can throw a TimeoutException
}
finally
{
    service.shutdown(); // clean up
}

The ExecutorService here is an execute-once-and-discard executor service, but you can replace it by a different executor service, possibly even make it a field or something. For this example this should be enough.

[Frank Hamilton]

Thank so much, it's work fine for me now.

[Rob Spoor]

You're welcome