Issue 1:
I have searched the issues of this repository and believe that this is not a duplicate.

I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

Dubbo version: 2.6.1

Operating System version: Linux version 3.10.0-693.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-16) (GCC) )

Java version: 1.8.0_171

zk & zk client version: 3.4.11

curator version: 4.0.1

不定时出现zookeeper session timeout，重连后消费端引用@reference 为空，日志如下

消费端jvm日志

04:22:37,427 WARN [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:1111] - Client session timed out, have not heard from server in 33959ms for sessionid 0x10000018d38000b
04:23:07,081 INFO [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:1159] - Client session timed out, have not heard from server in 33959ms for sessionid 0x10000018d38000b, closing socket connection and attempting reconnect
04:23:09,992 INFO [main-EventThread][state.ConnectionStateManager:237] - State change: SUSPENDED
04:23:10,186 INFO [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:1035] - Opening socket connection to server hostname/172.16.10.121:2181. Will not attempt to authenticate using SASL (unknown error)
04:23:10,804 INFO [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:877] - Socket connection established to hostname/172.16.10.121:2181, initiating session
04:23:10,998 WARN [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:1288] - Unable to reconnect to ZooKeeper service, session 0x10000018d38000b has expired
04:23:11,066 INFO [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:1157] - Unable to reconnect to ZooKeeper service, session 0x10000018d38000b has expired, closing socket connection
04:23:11,164 WARN [main-EventThread][curator.ConnectionState:372] - Session expired event received
04:23:12,502 INFO [main-EventThread][zookeeper.ZooKeeper:441] - Initiating client connection, connectString=hostname:2181 sessionTimeout=60000 watcher=org.apache.curator.ConnectionState@67f639d3
04:23:13,599 INFO [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:1035] - Opening socket connection to server hostname/172.16.10.121:2181. Will not attempt to authenticate using SASL (unknown error)
04:23:13,671 INFO [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:877] - Socket connection established to hostname/172.16.10.121:2181, initiating session
04:23:13,771 INFO [main-SendThread(hostname:2181)][zookeeper.ClientCnxn:1302] - Session establishment complete on server hostname/172.16.10.121:2181, sessionid = 0x10000018d38002b, negotiated timeout = 40000
04:23:13,672 INFO [main-EventThread][state.ConnectionStateManager:237] - State change: LOST
04:23:13,960 INFO [main-EventThread][state.ConnectionStateManager:237] - State change: RECONNECTED
04:23:14,708 INFO [main-EventThread][zookeeper.ClientCnxn:520] - EventThread shut down for session: 0x10000018d38000b

zookeeper服务器日志

2018-09-12 02:36:05,355 [myid:] - INFO [SessionTracker:ZooKeeperServer@354] - Expiring session 0x10000018dc20000, timeout of 40000ms exceeded
2018-09-12 02:36:05,356 [myid:] - INFO [SessionTracker:ZooKeeperServer@354] - Expiring session 0x10000018dc20002, timeout of 40000ms exceeded
2018-09-12 02:36:05,356 [myid:] - INFO [SessionTracker:ZooKeeperServer@354] - Expiring session 0x10000018dc20003, timeout of 40000ms exceeded
2018-09-12 02:36:05,356 [myid:] - INFO [ProcessThread(sid:0 cport:2181)::PrepRequestProcessor@487] - Processed session termination for sessionid: 0x10000018dc20000
2018-09-12 02:36:05,356 [myid:] - INFO [ProcessThread(sid:0 cport:2181)::PrepRequestProcessor@487] - Processed session termination for sessionid: 0x10000018dc20002
2018-09-12 02:36:05,357 [myid:] - INFO [ProcessThread(sid:0 cport:2181)::PrepRequestProcessor@487] - Processed session termination for sessionid: 0x10000018dc20003
2018-09-12 02:39:41,884 [myid:] - INFO [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@215] - Accepted socket connection from /172.16.10.123:33164
2018-09-12 02:39:41,888 [myid:] - INFO [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer@938] - Client attempting to establish new session at /172.16.10.123:33164
2018-09-12 02:39:41,996 [myid:] - INFO [SyncThread:0:ZooKeeperServer@683] - Established session 0x10000018d380001 with negotiated timeout 40000 for client /172.16.10.123:33164

Issue 2:
I have searched the issues of this repository and believe that this is not a duplicate.

I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

Dubbo version: 2.7.4.1

Java version: 1.8

Actual Result

dubbo/dubbo-common/src/main/java/org/apache/dubbo/rpc/model/ApplicationModel.java

Line 80
in
839d2a6

public static void iniFrameworkExts() {

Expected Result

initFrameworkExts