assertNotNull(pluginFiles);
        // Should return empty array when plugin directory doesn't exist
        assertEquals(0, pluginFiles.length);
    }

    public void test_getPluginJarFiles_withFilter() {
        FilenameFilter filter = (dir, name) -> name.endsWith(".jar");
        File[] pluginFiles = ResourceUtil.getPluginJarFiles(filter);
        assertNotNull(pluginFiles);