verify(mockClient).prepareSearch("test-index");
    }

    /**
     * Test: Verify that OnConnectListener is properly invoked
     */
    @Test
    public void testOnConnectListenerInvoked() {
        final AtomicBoolean listenerCalled = new AtomicBoolean(false);
        final OnConnectListener listener = () -> listenerCalled.set(true);

        fesenClient.addOnConnectListener(listener);