private static final EventBus INSTANCE;

    static {
        // There should be just one system class loader object in the whole JVM.
        synchronized (ClassLoader.getSystemClassLoader()) {
            // The key is a String, because the .class object would be different across classloaders.
            final EventBus singleton = (EventBus) System.getProperties().get(EventBus.class.getName());

            // Some other class loader loaded MessageBus earlier.
            if (singleton != null) {
                INSTANCE = singleton;
            } else {
                // Otherwise this classloader is the first one, let's create a singleton.
                // Make sure not to do any locking within this.
                INSTANCE = new EventBus();
                System.getProperties().put(EventBus.class.getName(), INSTANCE);
            }
        }
    }

    public static EventBus getInstance() {
        return INSTANCE;
    }