fix(nacos): fix issue #859

spring-cloud-alibaba-nacos-config/src/main/java/com/alibaba/cloud/nacos/NacosConfigProperties.java

@@ -184,7 +184,7 @@ public class NacosConfigProperties {
 	 */
 	private List<Config> extConfig;
 
-	private ConfigService configService;
+	private static ConfigService CONFIG_SERVICE;
 
 	// todo sts support
 
@@ -402,8 +402,8 @@ public class NacosConfigProperties {
 
 	public ConfigService configServiceInstance() {
 
-		if (null != configService) {
-			return configService;
+		if (null != CONFIG_SERVICE) {
+			return CONFIG_SERVICE;
 		}
 
 		Properties properties = new Properties();
@@ -430,8 +430,8 @@ public class NacosConfigProperties {
 		}
 
 		try {
-			configService = NacosFactory.createConfigService(properties);
-			return configService;
+			CONFIG_SERVICE = NacosFactory.createConfigService(properties);
+			return CONFIG_SERVICE;
 		}
 		catch (Exception e) {
 			log.error("create config service error!properties={},e=,", this, e);

spring-cloud-alibaba-nacos-discovery/src/main/java/com/alibaba/cloud/nacos/NacosDiscoveryProperties.java

@@ -182,9 +182,9 @@ public class NacosDiscoveryProperties {
 	@Autowired
 	private Environment environment;
 
-	private NamingService namingService;
+	private static NamingService NAMING_SERVICE;
 
-	private NamingMaintainService namingMaintainService;
+	private static NamingMaintainService NAMING_MAINTAIN_SERVICE;
 
 	@PostConstruct
 	public void init() throws SocketException {
@@ -465,35 +465,35 @@ public class NacosDiscoveryProperties {
 
 	public NamingService namingServiceInstance() {
 
-		if (null != namingService) {
-			return namingService;
+		if (null != NAMING_SERVICE) {
+			return NAMING_SERVICE;
 		}
 
 		try {
-			namingService = NacosFactory.createNamingService(getNacosProperties());
+			NAMING_SERVICE = NacosFactory.createNamingService(getNacosProperties());
 		}
 		catch (Exception e) {
 			log.error("create naming service error!properties={},e=,", this, e);
 			return null;
 		}
-		return namingService;
+		return NAMING_SERVICE;
 	}
 
 	public NamingMaintainService namingMaintainServiceInstance() {
 
-		if (null != namingMaintainService) {
-			return namingMaintainService;
+		if (null != NAMING_MAINTAIN_SERVICE) {
+			return NAMING_MAINTAIN_SERVICE;
 		}
 
 		try {
-			namingMaintainService = NamingMaintainFactory
+			NAMING_MAINTAIN_SERVICE = NamingMaintainFactory
 					.createMaintainService(getNacosProperties());
 		}
 		catch (Exception e) {
 			log.error("create naming service error!properties={},e=,", this, e);
 			return null;
 		}
-		return namingMaintainService;
+		return NAMING_MAINTAIN_SERVICE;
 	}
 
 	private Properties getNacosProperties() {