Extract default nameserver constant

broker/src/main/java/org/apache/rocketmq/broker/BrokerStartup.java

@@ -234,7 +234,7 @@ public class BrokerStartup {
         if (properties == null) {
             return;
         }
-        String rmqAddressServerDomain = properties.getProperty("rmqAddressServerDomain", "jmenv.tbsite.net");
+        String rmqAddressServerDomain = properties.getProperty("rmqAddressServerDomain", MixAll.DEFAULT_NAMESRV_ADDR_LOOKUP);
         String rmqAddressServerSubGroup = properties.getProperty("rmqAddressServerSubGroup", "nsaddr");
         System.setProperty("rocketmq.namesrv.domain", rmqAddressServerDomain);
         System.setProperty("rocketmq.namesrv.domain.subgroup", rmqAddressServerSubGroup);

common/src/main/java/org/apache/rocketmq/common/MixAll.java

@@ -52,7 +52,8 @@ public class MixAll {
     public static final String NAMESRV_ADDR_ENV = "NAMESRV_ADDR";
     public static final String NAMESRV_ADDR_PROPERTY = "rocketmq.namesrv.addr";
     public static final String MESSAGE_COMPRESS_LEVEL = "rocketmq.message.compressLevel";
-    public static final String WS_DOMAIN_NAME = System.getProperty("rocketmq.namesrv.domain", "jmenv.tbsite.net");
+    public static final String DEFAULT_NAMESRV_ADDR_LOOKUP = "jmenv.tbsite.net";
+    public static final String WS_DOMAIN_NAME = System.getProperty("rocketmq.namesrv.domain", DEFAULT_NAMESRV_ADDR_LOOKUP);
     public static final String WS_DOMAIN_SUBGROUP = System.getProperty("rocketmq.namesrv.domain.subgroup", "nsaddr");
     // http://jmenv.tbsite.net:8080/rocketmq/nsaddr
     public static final String WS_ADDR = "http://" + WS_DOMAIN_NAME + ":8080/rocketmq/" + WS_DOMAIN_SUBGROUP;