static RaftRegistryServiceImpl getInstance() {
        if (instance == null) {
            synchronized (RaftRegistryServiceImpl.class) {
                if (instance == null) {
                    instance = new RaftRegistryServiceImpl();
                }
            }
        }
        return instance;
    }
@Test
    public void testRefreshTokenSuccess() throws IOException, NoSuchMethodException, InvocationTargetException, IllegalAccessException, NoSuchFieldException {
        String jwtToken = "newToken";
        String responseBody = "{\"code\":\"200\",\"message\":\"success\",\"data\":\"" + jwtToken + "\",\"success\":true}";

        try (MockedStatic<HttpClientUtil> mockedStatic = Mockito.mockStatic(HttpClientUtil.class)) {

            CloseableHttpResponse mockResponse = mock(CloseableHttpResponse.class);
            StatusLine mockStatusLine = mock(StatusLine.class);

            when(mockResponse.getEntity()).thenReturn(new StringEntity(responseBody));
            when(mockResponse.getStatusLine()).thenReturn(mockStatusLine);
            when(mockStatusLine.getStatusCode()).thenReturn(HttpStatus.SC_OK);


            when(HttpClientUtil.doPost(any(String.class), any(Map.class), any(Map.class), any(int.class)))
                .thenReturn(mockResponse);


            Method refreshTokenMethod = RaftRegistryServiceImpl.class.getDeclaredMethod("refreshToken", String.class);
            refreshTokenMethod.setAccessible(true);
            refreshTokenMethod.invoke(RaftRegistryServiceImpl.getInstance(), "127.0.0.1:8092");
            Field jwtTokenField = RaftRegistryServiceImpl.class.getDeclaredField("jwtToken");
            jwtTokenField.setAccessible(true);
            String jwtTokenAct = (String) jwtTokenField.get(null);


            assertEquals(jwtToken, jwtTokenAct);

        }
    }