Lots of zookeeper cleanup error when dubbo shutdown

• 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: 3.0.3-SNAPSHOT
• Operating System version: macOS
• Java version: 1.8

Steps to reproduce this issue

1. Run test org.apache.dubbo.config.spring.reference.javaconfig.JavaConfigReferenceBeanTest#testReferenceBean

Actual Result

What actually happens?

Lots of zookeeper cleanup error when dubbo shutdown, and shutdown is slowdown:

16:47:25.897 [main-SendThread(localhost:2181)] INFO org.apache.zookeeper.ClientCnxn - Socket error occurred: localhost/127.0.0.1:2181: Connection refused
16:47:25.898 [main-SendThread(localhost:2181)] DEBUG org.apache.zookeeper.ClientCnxnSocketNIO - Ignoring exception during shutdown input
java.nio.channels.ClosedChannelException: null
	at sun.nio.ch.SocketChannelImpl.shutdownInput(SocketChannelImpl.java:780)
	at sun.nio.ch.SocketAdaptor.shutdownInput(SocketAdaptor.java:399)
	at org.apache.zookeeper.ClientCnxnSocketNIO.cleanup(ClientCnxnSocketNIO.java:200)
	at org.apache.zookeeper.ClientCnxn$SendThread.cleanup(ClientCnxn.java:1250)
	at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1174)
16:47:25.898 [main-SendThread(localhost:2181)] DEBUG org.apache.zookeeper.ClientCnxnSocketNIO - Ignoring exception during shutdown output
java.nio.channels.ClosedChannelException: null
	at sun.nio.ch.SocketChannelImpl.shutdownOutput(SocketChannelImpl.java:797)
	at sun.nio.ch.SocketAdaptor.shutdownOutput(SocketAdaptor.java:407)
	at org.apache.zookeeper.ClientCnxnSocketNIO.cleanup(ClientCnxnSocketNIO.java:207)
	at org.apache.zookeeper.ClientCnxn$SendThread.cleanup(ClientCnxn.java:1250)
	at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1174)
16:47:25.979 [main-SendThread(localhost:2181)] INFO org.apache.zookeeper.ClientCnxn - Opening socket connection to server localhost/127.0.0.1:2181. Will not attempt to authenticate using SASL (unknown error)
16:47:25.979 [main-SendThread(localhost:2181)] INFO org.apache.zookeeper.ClientCnxn - Socket error occurred: localhost/127.0.0.1:2181: Connection refused
16:47:25.979 [main-SendThread(localhost:2181)] DEBUG org.apache.zookeeper.ClientCnxnSocketNIO - Ignoring exception during shutdown input
java.nio.channels.ClosedChannelException: null
	at sun.nio.ch.SocketChannelImpl.shutdownInput(SocketChannelImpl.java:780)
	at sun.nio.ch.SocketAdaptor.shutdownInput(SocketAdaptor.java:399)
	at org.apache.zookeeper.ClientCnxnSocketNIO.cleanup(ClientCnxnSocketNIO.java:200)
	at org.apache.zookeeper.ClientCnxn$SendThread.cleanup(ClientCnxn.java:1250)
	at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1174)
16:47:25.979 [main-SendThread(localhost:2181)] DEBUG org.apache.zookeeper.ClientCnxnSocketNIO - Ignoring exception during shutdown output
java.nio.channels.ClosedChannelException: null
	at sun.nio.ch.SocketChannelImpl.shutdownOutput(SocketChannelImpl.java:797)
	at sun.nio.ch.SocketAdaptor.shutdownOutput(SocketAdaptor.java:407)
	at org.apache.zookeeper.ClientCnxnSocketNIO.cleanup(ClientCnxnSocketNIO.java:207)
	at org.apache.zookeeper.ClientCnxn$SendThread.cleanup(ClientCnxn.java:1250)
	at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1174)

dubbo-8711-error.txt