assertEquals(num, valueSet2.size());
    }

    @Test
    public void test_getLimitDocNum() throws Exception {
        assertEquals(10, ESSourceReader.getLimitDocNum(100, 10, -1));
        assertEquals(25, ESSourceReader.getLimitDocNum(50, 50, -1));
        assertEquals(10, ESSourceReader.getLimitDocNum(50, 50, 10));
    }

    @Test
    public void test_sort() throws Exception {