cos.flush();
        assertFalse(cos.isInMemory());
        File file = cos.getFile();
        assertTrue(file.exists());
        cos.close();
    }

    @Test
    public void testLargeData() throws IOException {
        // Test with large data exceeding typical threshold
        ContentOutputStream cos = new ContentOutputStream(100, Curl.tmpDir);
        byte[] largeData = new byte[500];