#vulnerable code 
                                @Test
    public void testCreateEventConsumerFailsOnConnectionFailure(final TestContext ctx) {

        // GIVEN a client that already tries to create a telemetry sender for "tenant"
        ProtonConnection con = mock(ProtonConnection.class);
        DisconnectHandlerProvidingConnectionFactory connectionFactory = new DisconnectHandlerProvidingConnectionFactory(con);
        final Async connected = ctx.async();
        HonoClientImpl client = new HonoClientImpl(vertx, connectionFactory);
        client.connect(new ProtonClientOptions(), ctx.asyncAssertSuccess(ok -> connected.complete()));
        connected.await(200);

        final Async disconnected = ctx.async();
        client.createEventConsumer("tenant", msg -> {}, ctx.asyncAssertFailure(cause -> {
            disconnected.complete();
        }));

        // WHEN the underlying connection fails
        connectionFactory.getDisconnectHandler().handle(con);

        // THEN all creation requests are failed
        disconnected.await(200);
    } 
                            #location 18 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Test
    public void testCreateEventConsumerFailsOnConnectionFailure(final TestContext ctx) {

        // GIVEN a client that already tries to create a telemetry sender for "tenant"
        final Async connected = ctx.async();
        final HonoClientImpl client = new HonoClientImpl(vertx, connectionFactory);
        client.connect(new ProtonClientOptions(), ctx.asyncAssertSuccess(ok -> connected.complete()));
        connected.await();

        final Async disconnected = ctx.async();
        client.createEventConsumer("tenant", msg -> {}, ctx.asyncAssertFailure(cause -> {
            disconnected.complete();
        }));

        // WHEN the underlying connection fails
        connectionFactory.getDisconnectHandler().handle(con);

        // THEN all creation requests are failed
        disconnected.await();
    }