More odd behaviour

Ok guys, I’ve been working on an application to start, monitor and stop the River core services (LUS, TM, Space,  Class Server). 

I’m using an event driven model using Lookup Cache and ServiceDiscoveryListener.

There is a ServiceDiscoveryManager that is started to set up the LookupCaches

      mgr = new LookupDiscoveryManager(DiscoveryGroupManagement.ALL_GROUPS,

                                       null,         // unicast locators

                                       null);   // DiscoveryListener

      sdm = new ServiceDiscoveryManager(mgr, new LeaseRenewalManager());

I was having trouble stopping the LUS.  I had originally used the SDM directly with a DiscoveryListener, but kept getting uncatchable exceptions from the SDM when I killed the LUS.  I can’t terminate the SDM in this app (that stops the exception if you do), because I want to monitor the system as long as the app is running.

So, I tried to use a LookupCache for the ServiceRegistrar…

      classes = new Class[] {ServiceRegistrar.class};                               

      template = new ServiceTemplate(null,

                                     classes,

                                     null);

      lusCache = sdm.createLookupCache(template, null, lusMonitor);

I use one for the space and one the TM as well.

In the lusMonitor code I have this…

  public void serviceAdded(ServiceDiscoveryEvent evt)

  {

    ServiceItem si = evt.getPostEventServiceItem();

    Object service = si.service;

    if(service instanceof ServiceRegistrar)

    {

      sp.setStatusRunning();

    }

  }

  public void serviceRemoved(ServiceDiscoveryEvent serviceDiscoveryEvent)

  {

    sp.setStatusStopped();

  }

And the code that kills the LUS is in another class…

  public void stopLUS()

  {

    LookupCache cache = csm.getLUSCache();

    ServiceItem si = cache.lookup(null);

    Object lusProxy = si.service;

    if(lusProxy instanceof Administrable)

    {

      try

      {

        Object admin = ((Administrable)lusProxy).getAdmin();

        DestroyAdmin da = (DestroyAdmin)admin;

        cache.discard(si);

        da.destroy();

      }

      catch(Exception ex)

      {

        System.out.println("Error getting LUS DestroyAdmin");

        ex.printStackTrace();

      }

    }

  }

Ok, so, when the LUS starts, the ServiceAdded method in the ServiceDiscoveryListener (lusMonitor) is quickly invoked.

When the LUS is killed, it takes about 10 minutes for that event to be fired.  The LUS is dead, dead, dead, I assume it has been discarded from the LookupCache.

This works almost instantly for the space and TM, but it looks like a lease expiration or something is holding up the discard event for the LUS.

Any ideas on how to get around this?

BAR

Thanks for the responses guys.  I figured it was a lease waiting to expire.  I guess I can get around it by setting the LUS status to be “down” right after the destroy() call, because that does indeed kill the LUS.

I’d like to use this problem as something I think is important for future River use.  This is an app I should not have to be writing.

There was a nice, really simple UI in Jini 1 that you could start and stop the cores services with,  this type of app really needs to come back into River.

We are finding our Systems Admin types do not want to deal with things like configuration and start scripts.  They want a nice clean UI they can use.

We got complaints about them having to use “ps” commands to kill the River core services.

BAR