public long getArrival() {
        return this.arrival;
    }
@Test
    public void testGetArrival() throws Exception {
        final GELFMessageChunk chunk = buildChunk();
        final long l = Tools.nowUTC().getMillis();
        final long arrival = chunk.getArrival();
        assertTrue(l - arrival < 5000L); // delta shmelta
    }