public static Map<String, String> parsePropertyValue2Map(Properties properties, String propertyName) {
        String rawLabels = properties.getProperty(propertyName,
                System.getProperty(propertyName, System.getenv(propertyName)));
        if (StringUtils.isBlank(rawLabels)) {
            LOGGER.info("no value found for property key: {}", propertyName);
            return new HashMap<>(2);
        }
        return parseRawLabels(rawLabels);
    }
@Test
    void testParsePropertyValue2Map() {
        Properties properties = new Properties();
        String property = "property";
        String rawValue = "k1 = v1, k2 = v2";
        properties.put(property, rawValue);
        String property1 = "property2";
        String rawValue1 = "k11=v11, kk2";
        properties.put(property1, rawValue1);
        
        Map<String, String> m = ConnLabelsUtils.parsePropertyValue2Map(properties, property);
        assertEquals(2, m.size());
        assertEquals("v1", m.get("k1"));
        assertEquals("v2", m.get("k2"));
        
        Map<String, String> m1 = ConnLabelsUtils.parsePropertyValue2Map(properties, property1);
        assertEquals(1, m1.size());
        assertEquals("v11", m1.get("k11"));
        assertNull(m1.get("kk2"));
        
        m = ConnLabelsUtils.mergeMapByOrder(m, m1);
        assertEquals(3, m.size());
        assertEquals("v1", m.get("k1"));
        assertEquals("v2", m.get("k2"));
        assertEquals("v11", m.get("k11"));
        
        m = ConnLabelsUtils.addPrefixForEachKey(m, "test_prefix");
        assertEquals(3, m.size());
        m.forEach((k, v) -> {
            assertTrue(k.startsWith("test_prefix"));
        });
    }