thread.start();
        thread.join(1000);

        String output = thread.getOutput();
        assertTrue(output.contains("test line"));
    }

    public void test_run_largeInput() throws InterruptedException {
        StringBuilder largeInput = new StringBuilder();
        for (int i = 0; i < 5000; i++) {
            largeInput.append("Line number ").append(i).append("\n");
        }