public static List<CommonUpstream> convertCommonUpstreamList(final List<? extends CommonUpstream> upstreamList) {
        return Optional.ofNullable(upstreamList)
                .orElse(Collections.emptyList())
                .stream()
                .map(upstream -> new CommonUpstream(upstream.getProtocol(),
                        upstream.getUpstreamHost(), upstream.getUpstreamUrl(),
                        upstream.isStatus(), upstream.getTimestamp()))
                .collect(Collectors.toList());
    }
@Test
    public void convertCommonUpstreamList() {
        List<DivideUpstream> existDivideUpstreams = new ArrayList<>();
        DivideUpstream divideUpstream = CommonUpstreamUtils.buildDivideUpstream("http", HOST, PORT);
        existDivideUpstreams.add(divideUpstream);

        List<CommonUpstream> commonUpstreams = CommonUpstreamUtils.convertCommonUpstreamList(existDivideUpstreams);
        Assert.assertNotNull(commonUpstreams);
        Assert.assertEquals(1, commonUpstreams.size());
        Assert.assertEquals("http", commonUpstreams.get(0).getProtocol());
        Assert.assertEquals(HOST + ":" + PORT, commonUpstreams.get(0).getUpstreamUrl());
        Assert.assertNotNull(CommonUpstreamUtils.convertCommonUpstreamList(null));
        Assert.assertNotNull(CommonUpstreamUtils.convertCommonUpstreamList(new ArrayList<>()));
    }