public boolean isTimeout() {
        return System.currentTimeMillis() - start > timeout;
    }
@Test
    public void testIsTimeOut() throws Exception {
        MessageFuture messageFuture = new MessageFuture();
        messageFuture.setTimeout(TIME_OUT_FIELD);
        assertThat(messageFuture.isTimeout()).isFalse();
        Thread.sleep(TIME_OUT_FIELD + 1);
        assertThat(messageFuture.isTimeout()).isTrue();

    }