SNMP4J Agent and Net-SNMP "client" - snmp

Question

I'm still learning SNMP, so be gentle please.
I did an agent with snmp4j and it seems to be working, i have a scalar that should register how much time has passed since the agent started.
I just have to do the agent, then i would like to see the value of the scalar with net-snmp.
The problem is, when i start the agent i set the my scalar SystemUpTime to 0, then i try to update SystemUpTime everytime someone tries to check it with net-snmp that value doesnt change.
How can i get my agent to update SystemUpTime everytime something tries to access it?
I have a method MOScalar getSystemUpTime since it updates SystemUpTime before returning it and i thought that it would do the job, but it is not working.
What do u guys sugest?
EDIT ( my agent code, ive taken off some of the mandatory methods to short this thing a bit )
public class Agent extends BaseAgent {
// not needed but very useful of course
static {
LogFactory.setLogFactory(new Log4jLogFactory());
}
static long starttime=0;
private String address;
static OID oid= new OID(".1.3.6.1.4.1.1.1.0");
public static MOScalar sysUpTime;
private static MOFactory moFactory =
DefaultMOFactory.getInstance();
public Agent(String address) throws IOException {
// These files does not exist and are not used but has to be specified
// Read snmp4j docs for more info
super(new File("conf.agent"), new File("bootCounter.agent"),
new CommandProcessor(
new OctetString(MPv3.createLocalEngineID())));
this.address = address;
}
/**
* Clients can register the MO they need
*/
public void registerManagedObject(ManagedObject mo) {
try {
server.register(mo, null);
System.out.println("MIB FILLED!");
} catch (DuplicateRegistrationException ex) {
throw new RuntimeException(ex);
}
}
/**
* Start method invokes some initialization methods needed to
* start the agent
* #throws IOException
*/
public void start() throws IOException {
init();
// This method reads some old config from a file and causes
// unexpected behavior.
// loadConfig(ImportModes.REPLACE_CREATE);
addShutdownHook();
getServer().addContext(new OctetString("public"));
finishInit();
run();
sendColdStartNotification();
}
protected void unregisterManagedObjects() {
// here we should unregister those objects previously registered...
}
/**
* The table of community strings configured in the SNMP
* engine's Local Configuration Datastore (LCD).
*
* We only configure one, "public".
*/
protected void addCommunities(SnmpCommunityMIB communityMIB) {
Variable[] com2sec = new Variable[] {
new OctetString("public"), // community name
new OctetString("cpublic"), // security name
getAgent().getContextEngineID(), // local engine ID
new OctetString("public"), // default context name
new OctetString(), // transport tag
new Integer32(StorageType.nonVolatile), // storage type
new Integer32(RowStatus.active) // row status
};
}
public static void main(String[] args) throws IOException, InterruptedException {
Agent agent = new Agent("127.0.0.1/6666");
sysUpTime=moFactory.createScalar(oid,
moFactory.createAccess(MOAccessImpl.ACCESSIBLE_FOR_READ_ONLY),
new TimeTicks(0));
starttime=System.currentTimeMillis();
agent.registerManagedObject(sysUpTime);
agent.start();
while(true) {
System.out.println("Agent running...");
Thread.sleep(5000);
}
}
public MOScalar getSystemID() {
Variable var = new Integer32((int) (System.currentTimeMillis() - starttime));
sysUpTime.setValue(var);
return sysUpTime;
}
}