Hi Rupert,
I'm not entirely sure I understand what it is you're trying to
achieve. Are you saying you have many services which come and go
(which you describe as "applications") and you want notifications of
when they dis/appear so you can then get access to their MBeans?
If that's right, a possible approach would be to use a
ServiceDiscoveryManager to create a LookupCache. The LookupCache
would always know what services are around. As a side-effect, when
you create the LookupCache
(ServiceDiscoveryManager.createLookupCache(ServiceTemplate,
ServiceItemFilter, ServiceDiscoveryListener)) your implementation of
ServiceDiscoveryListener can handle your accessing the MBeans when
things appear and dropping them when they go.
Does that help? If not, can you clarify a bit more what you're trying
to do and I'll see if I can help.
Cheers,
Tom
On Thu, Dec 2, 2010 at 4:50 PM, Rupert Smith
<rupertlssm...@googlemail.com> wrote:
> Hi,
>
> I have successfully registered a JMX RMI Connector with in a registry in an
> app process, looked it up by service type, and queried it for available
> MBeans in a management process. I have many app instances starting/stopping,
> and a single management instance that needs to know when the applications
> come up or down, and to obtain access to their MBeans when they do.
>
> To get started, I have run an example lookup on the management process. Now
> instead of a pull interface (client driven poll), I want, if possible a
> registry driven push interface, registry will tell the management process as
> service become available/unavailable.
>
> First of all, I'd like to know, am I taking the right approach? Is the
> ServiceRegistrar.notify(...) method capable of doing what I want it to do
> wrt a push driven interface between the registry and the management process?
> There's not much documentation around so its hard to know. I was expecting a
> remote call-back from the registry every time a matching service changes its
> registration.
>
> If I can't get it to work, I'll just fall back to a periodic polling
> mechansim.
>
> See below for the gruesome details, and many thanks for any help you are
> able to give me.
>
> Rupert
>
> =====================================
>
> Here's some code:
>
> public class MBeanJiniListener extends StartStopLifecycleBase implements
> RemoteEventListener, Serializable
> {
> ...
> private void startListeningForJMXConnectors() throws IOException,
> ClassNotFoundException
> {
> ServiceRegistrar registrar =
> JiniUtils.getRegistrar(jiniRegistryURL);
>
> log.fine("registrar is: " + registrar);
>
> jmxConnections = new HashMap<JMXConnector, MBeanServerConnection>();
>
> Class[] classes = new Class[] { JMXConnector.class };
> Entry[] serviceAttrs =
> new Entry[] { new
> com.sun.jini.lookup.entry.BasicServiceType(JMX_CONNECTOR_SERVICE_NAME) };
>
> ServiceTemplate template = new ServiceTemplate(null, classes,
> serviceAttrs);
>
> eventRegistration =
> registrar.notify(template,
> ServiceRegistrar.TRANSITION_MATCH_NOMATCH, this, null,
> Long.MAX_VALUE);
> }
> }
>
> This fails with a ClassNotFoundException on this line:
>
> eventRegistration =
> registrar.notify(template,
> ServiceRegistrar.TRANSITION_MATCH_NOMATCH, this, null,
> Long.MAX_VALUE)
>
> ...
> Caused by: java.lang.ClassNotFoundException:
> com.rapidaddition.fix.management.jini.MBeanJiniListener
> at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
> at java.security.AccessController.doPrivileged(Native Method)
> at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
> at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
> at
> net.jini.loader.pref.PreferredClassLoader.loadClass(PreferredClassLoader.java:922)
> at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
> at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:334)
> at java.lang.Class.forName0(Native Method)
> at java.lang.Class.forName(Class.java:264)
> at
> net.jini.loader.pref.PreferredClassProvider.loadClass(PreferredClassProvider.java:613)
> at java.rmi.server.RMIClassLoader.loadClass(RMIClassLoader.java:264)
> at
> sun.rmi.server.MarshalInputStream.resolveClass(MarshalInputStream.java:214)
> at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1592)
> at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1513)
> at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1749)
> at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1346)
> at java.io.ObjectInputStream.readObject(ObjectInputStream.java:368)
> at sun.rmi.server.UnicastRef.unmarshalValue(UnicastRef.java:324)
> at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:307)
> ... 9 more
>
> I am using 'httpd.sh' and 'jrmp-reggie.sh' scripts from the hello example,
> bundled with Apache River 2.1.1. Both have been modified to include all my
> project .jars. That is:
>
> 'config/start-reggie.config'
>
> ...
> private static codebase =
> ConfigUtil.concat(
> new Object[] {
> "http://";, ConfigUtil.getHostName(),
> ":8080/reggie-dl.jar",
> " ",
> "http://";, ConfigUtil.getHostName(),
> ":8080/jsk-dl.jar",
> " ",
> "http://";, ConfigUtil.getHostName(),
> ":8080/genzero-mgt-1.2-beta2-SNAPSHOT.jar",
> " ",
> "http://";, ConfigUtil.getHostName(),
> ":8080/genzero-1.2-beta2-SNAPSHOT.jar",
> " ",
> "http://";, ConfigUtil.getHostName(),
> ":8080/genzero-api-1.2-beta2-SNAPSHOT.jar",
> " ",
> "http://";, ConfigUtil.getHostName(),
> ":8080/samples-1.2-beta2-SNAPSHOT.jar"
> } );
> ...
>
> and 'scripts/httpd.sh'
>
> ...
> java -jar ../../../../../../../lib/classserver.jar -port 8080 -dir
> lib:../../../../../../../lib-dl:/home/rupert/rapid/genzero/genzero-trunk/genzero-api/target:/home/rupert/rapid/genzero/genzero-trunk/genzero/target:/home/rupert/rapid/genzero/genzero-trunk/samples/target:/home/rupert/rapid/genzero/genzero-trunk/genzero-mgt/target
> $*
>
