void testForceCleanup() {
        TestResource resource1 = new TestResource("cleanup1");
        TestResource resource2 = new TestResource("cleanup2");

        resourceManager.registerResource(resource1);
        resourceManager.registerResource(resource2);

        assertFalse(resource1.isClosed());
        assertFalse(resource2.isClosed());

        int cleaned = resourceManager.forceCleanup();

    }

    /**
     * Register a resource for tracking
     *
     * @param resource the resource to track
     * @return resource ID for tracking
     */
    public String registerResource(AutoCloseable resource) {
        if (resource == null) {
            throw new IllegalArgumentException("Resource cannot be null");
        }

        String resourceId = generateResourceId(resource);