assertTrue("Buffer should be limited to 10 items", lines.length <= 10);
        assertTrue("Last lines should be kept", output.contains("line15"));
    }

    public void test_run_maxBufferSizeConstant() {
        assertEquals(1000, InputStreamThread.MAX_BUFFER_SIZE);
    }

    public void test_run_withMaxBufferSize() throws InterruptedException {
        StringBuilder inputBuilder = new StringBuilder();