public static String valueOf(String regionId) {
        if (ObjectHelper.isEmpty(regionId)) {
            throw new IllegalArgumentException("Unexpected empty parameter: regionId.");
        } else {
            String endpoint = REGIONS.get(regionId.toLowerCase());
            if (ObjectHelper.isNotEmpty(endpoint)) {
                return endpoint;
            } else {
                throw new IllegalArgumentException("Unexpected regionId: " + regionId);
            }
        }
    }
@Test
    public void testRegions() {
        assertEquals("obs.af-south-1.myhuaweicloud.com", OBSRegion.valueOf("af-south-1"));
        assertEquals("obs.ap-southeast-2.myhuaweicloud.com", OBSRegion.valueOf("ap-southeast-2"));
        assertEquals("obs.ap-southeast-3.myhuaweicloud.com", OBSRegion.valueOf("ap-southeast-3"));
        assertEquals("obs.cn-east-3.myhuaweicloud.com", OBSRegion.valueOf("cn-east-3"));
        assertEquals("obs.cn-east-2.myhuaweicloud.com", OBSRegion.valueOf("cn-east-2"));
        assertEquals("obs.cn-north-1.myhuaweicloud.com", OBSRegion.valueOf("cn-north-1"));
        assertEquals("obs.cn-south-1.myhuaweicloud.com", OBSRegion.valueOf("cn-south-1"));
        assertEquals("obs.ap-southeast-1.myhuaweicloud.com", OBSRegion.valueOf("ap-southeast-1"));
        assertEquals("obs.sa-argentina-1.myhuaweicloud.com", OBSRegion.valueOf("sa-argentina-1"));
        assertEquals("obs.sa-peru-1.myhuaweicloud.com", OBSRegion.valueOf("sa-peru-1"));
        assertEquals("obs.na-mexico-1.myhuaweicloud.com", OBSRegion.valueOf("na-mexico-1"));
        assertEquals("obs.la-south-2.myhuaweicloud.com", OBSRegion.valueOf("la-south-2"));
        assertEquals("obs.sa-chile-1.myhuaweicloud.com", OBSRegion.valueOf("sa-chile-1"));
        assertEquals("obs.sa-brazil-1.myhuaweicloud.com", OBSRegion.valueOf("sa-brazil-1"));
    }