public static String getServiceKey(Map<String, String> ps) {
        StringBuilder buf = new StringBuilder();
        String group = ps.get(GROUP_KEY);
        if (isNotEmpty(group)) {
            buf.append(group).append('/');
        }
        buf.append(ps.get(INTERFACE_KEY));
        String version = ps.get(VERSION_KEY);
        if (isNotEmpty(group)) {
            buf.append(':').append(version);
        }
        return buf.toString();
    }
@Test
    void testGetServiceKey() throws Exception {
        Map<String, String> map = new HashMap<String, String>();
        map.put(GROUP_KEY, "dubbo");
        map.put(INTERFACE_KEY, "a.b.c.Foo");
        map.put(VERSION_KEY, "1.0.0");
        assertThat(StringUtils.getServiceKey(map), equalTo("dubbo/a.b.c.Foo:1.0.0"));
    }