Port MBean from JBoss 4.x to JBoss 7

Question

we\'re currently in the process of porting some of our projects from JBoss 4.x to JBoss 7. So far everything seems to work fine, except for our MBeans, which we\'re commonly usi

Answer 1

Singleton EJB with @Startup? http://www.adam-bien.com/roller/abien/entry/singleton_the_simplest_possible_jmx

Answer 2

I think more concise way to do it is to use CDI extension. Please take a look at the solution we use:

@Documented
@Retention(value=RUNTIME)
@Target(value=TYPE)
@Inherited
public @interface MBean {
    String value() default "";
}

...

This is working code of CDI extension:

public class ManagementExtension implements Extension {

    private static Logger log = LoggerFactory
            .getLogger(ManagementExtension.class);

    public <T> void processInjectionTarget(@Observes ProcessInjectionTarget<T> pit) {

        // check if the MBean annotation is present
        AnnotatedType<T> at = pit.getAnnotatedType();
        if (at.isAnnotationPresent(MBean.class)) {
            // it makes sense to register JMX interfaces only for singletons
            if (!at.isAnnotationPresent(Singleton.class)) {
                log.warn("Ignoring attemt to register JMX interface for a non-singleton EJB: "
                        + at.getJavaClass().getName());
                return;
            }

            try {
                // decorate the InjectionTarget
                InjectionTarget<T> delegate = pit.getInjectionTarget();
                InjectionTarget<T> wrapper = new JmxInjectionTarget<T>(delegate, getObjectName(at));

                // change the InjectionTarget with the decorated one
                pit.setInjectionTarget(wrapper);
            } catch (Exception e) {
                log.warn("Cannot get JMX object name for: " + at.getJavaClass().getName(), e);
            }

        }
    }

    private <T> ObjectName getObjectName(AnnotatedType<T> at) throws MalformedObjectNameException {

        String name = at.getAnnotation(MBean.class).value();

        if (name.isEmpty()) {
            name = at.getJavaClass().getPackage().getName() + ":type="
                    + at.getJavaClass().getSimpleName();
        }

        return new ObjectName(name);
    }

    private class JmxInjectionTarget<T> implements InjectionTarget<T> {

        private final InjectionTarget<T> d;
        private final ObjectName objectName;

        public JmxInjectionTarget(InjectionTarget<T> delegate, ObjectName objectName) {
            this.d = delegate;
            this.objectName = objectName;
        }
        @Override
        public void dispose(T instance) {
            d.dispose(instance);
        }

        @Override
        public Set<InjectionPoint> getInjectionPoints() {
            return d.getInjectionPoints();
        }

        @Override
        public T produce(CreationalContext<T> ctx) {
            return d.produce(ctx);
        }

        @Override
        public void inject(T instance, CreationalContext<T> ctx) {
            d.inject(instance, ctx);
            //the next piece of code better be done in postConstruct but...
            //got no idea why but postConstruct never gets called
            //for Singleton EJB bean
            MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
            try {
                if(mBeanServer.isRegistered(objectName))
                mBeanServer.unregisterMBean(objectName);
                mBeanServer.registerMBean(instance, objectName);
            } catch (Exception e) {
                log.warn("Cannot register "+objectName, e);
                return;
            }
            log.info("added JMX registration for: " + objectName);
        }

        @Override
        public void postConstruct(T instance) {
            d.postConstruct(instance);
        }

        @Override
        public void preDestroy(T instance) {
            d.preDestroy(instance);
        }

    }
}

Then just mark your class by @Mbean annotation and will be automatically registered in Mbean server :

@Startup 
@Singleton 
@MBean("com.company=JmxBindName")
public class SomeService

Works like a charm )