public boolean save(HashMap<String, Object> vGroupMapping) {
        try {
            ObjectMapper objectMapper = new ObjectMapper();
            String jsonMapping = objectMapper.writeValueAsString(vGroupMapping);
            FileUtils.writeStringToFile(new File(storePath), jsonMapping, "UTF-8");
            return true;
        } catch (IOException e) {
            LOGGER.error("mapping relationship saved failed! ", e);
            return false;
        }
    }
@Test
    public void testSave() {
        HashMap<String, Object> vGroupMapping = new HashMap<>();
        vGroupMapping.put(VGROUP_NAME, UNIT);

        assertTrue(fileVGroupMappingStoreManager.save(vGroupMapping));

        File file = new File(STORE_PATH);
        assertTrue(file.exists());

        try {
            String content = FileUtils.readFileToString(file, StandardCharsets.UTF_8);
            assertEquals("{\"testVGroup\":\"testUnit\"}", content);
        } catch (IOException e) {
            fail("Failed to read the file content");
        }
    }